VEGETABLE CROP MANAGEMENT IN THE ARKANSAS VALLEY

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0158348
• Project Start Date: Jul 1, 2010
• Project End Date: Jun 30, 2015
• Program Code: [(N/A)]- (N/A)

Recipient Organization
COLORADO STATE UNIVERSITY
(N/A)
FORT COLLINS,CO 80523

Performing Department
Horticulture and Landscape Architecture

Non Technical Summary
Vegetable crop production has a long history in the Arkansas Valley of Colorado. Concurrent with the growth in population, there has been increasing pressure on land and water resources. Overall, many of the prime agricultural regions of Colorado are experiencing population growth-related pressures. Despite these issues, demographic changes have presented some opportunities for growers in the state. Namely, the demand for fresh and locally-grown produce has grown dramatically as reflected by the increase in the number and size of farmers markets and other direct marketing opportunities. With the increasing awareness of the importance of locally-grown foods, there is a desire for agricultural and municipal interests to better manage land and water resources. Improving on-farm irrigation efficiency is one component of this strategy. Statewide, the majority of vegetable crops are irrigated via gravity-flow furrows. However, there has been an expansion in more efficient methods of water delivery. To date, there is very little localized information available to growers to help them optimize water delivery via drip or sprinkler systems. As growers adopt drip irrigation, other forms of plasticulture including mulches and row covers can be more easily adopted. Another form of plasticulture, high tunnel production, can also be adopted. High tunnels can dramatically improve the marketing period for Colorado-grown crops. High tunnels and other season extension methods have the potential to sustain year-round production and enable growers to expand marketing opportunities. Irrigation water derived from the Arkansas River can be of poor quality. Many producers are using fairly saline water. Other solutes like selenium and nitrates can also contribute to water quality issues. A properly managed drip irrigation system may help reduce water quality problems associated with irrigation in the region. Unfortunately, there is very little site-specific information on ways to mitigate the effects of using saline water in a drip irrigation system. The Arkansas Valley has a long and successful history of vegetable seed production. Although seed production has diminished from its historical levels, there is still a sizable amount of conventional seed production in the Valley. In recent years, there has been a dramatic increase in organic vegetable production. Accordingly, demand for organic vegetable seed is growing rapidly as the USDA National Organic Program requires organic farmers to use certified organic seed when available. With this potential, there is the opportunity to re-establish the seed production industry in the Arkansas Valley. The information derived from this project could enhance growers profits, decrease environmental pollution, and generally advance the use of more sustainable agricultural practices. Improving marketing opportunities via season extension techniques will increase the availability of locally-grown foods to more Coloradoans. Overall, the expected results from these studies would optimize intensive production practices and revitalize the seed production industry in the Arkansas Valley

Animal Health Component

(N/A)

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
102	0210	1060	20%
102	1420	1060	10%
102	1451	1060	10%
102	1461	1060	10%
111	0210	1060	20%
111	1420	1060	10%
111	1451	1060	10%
111	1461	1060	10%

Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships; 111 - Conservation and Efficient Use of Water;

Subject Of Investigation
1461 - Peppers; 0210 - Water resources; 1451 - Onion, garlic, leek, shallot; 1420 - Melons;

Field Of Science
1060 - Biology (whole systems);

Keywords

plasticulture

onions

watermelon

cantaloupe

peppers

drip irrigation

organic seed

salinity

vegetables

Goals / Objectives
A. General: The goal of this program is to help improve the economic and environmental aspects of vegetable crop production in the Arkansas Valley of Southeastern Colorado. The principal vegetable crops grown in the Arkansas Valley are onions, cantaloupe, watermelon, and peppers. B. Specific: Upon completion of this research the following questions will be addressed: 1. What are the optimum production techniques for vegetables produced with drip irrigation, plastic mulches, and row covers 2. How does drip and furrow irrigation affect the movement of salts and nitrate-nitrogen in the soil profile in vegetable production systems 3. What kinds of vegetable crops can be produced in high tunnels in the Arkansas Valley 4. What are the techniques for feasibly producing organic vegetable seeds in the Arkansas Valley

Project Methods
Questions 1 will look at different types of plasticulture production systems in replicated field trials. Specifically, different plastic mulch types and row cow covers will be evaluated with different vegetable and specialty crops. Additionally, the influence of planting date, establishment method, and crop variety will be examined. Data collected will be crop yield and quality, changes in crop maturity, pest response, and economic feasibility. Experiments will be conducted at Colorado State Universitys Arkansas Valley Research Center in Rocky Ford, CO. Question 2 will examine how solutes move in the soil profile under drip and furrow irrigation systems. Soil samples will be taken at different locations and depths in the vegetable bed to assess soil constituents. Variables to be examined include salt distribution and nitrate-nitrogen content in the soil profile. Data on crop yield and quality, spatial distribution of salinity in the soil, and overall irrigation water requirements will be collected. Experiments will be conducted at Colorado State Universitys Arkansas Valley Research Center in Rocky Ford, CO. Question 3 will determine the production logistics and economic feasibility of growing vegetable crops in unheated high tunnels. Several warm and cool-season vegetables will be evaluated. Production variables including planting and harvesting dates and bed configuration will be tested. Data on yield, quality, length of marketing period, and pest pressure will be denoted. Experiments will be conducted at Colorado State Universitys Arkansas Valley Research Center in Rocky Ford, CO and with several local growers with high tunnel structures. Question 4 will determine the feasibility of producing organic vegetable seeds from cucurbit and solanaceous crops. The yield and quality of the seeds will be closely evaluated. In addition, production requirements for organic pest control will be determined. Experiments will be conducted at Colorado State Universitys Arkansas Valley Research Center in Rocky Ford, CO. The Center has a four acre site that has completed the requirements for organic production.

Progress 07/01/10 to 06/30/15

Outputs
Target Audience:The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project was responisble for generating numerous opportunities for training and professional development via field days, tours, industry meetings, and professional acedemic conferences. How have the results been disseminated to communities of interest?Information from this projected was disseminated via field days, public grower presentaions, technical reports, and via the web site for the Colorado Fruit and Vegetable Growers Association (www.coloradoproduce.org). What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Goal 1: In the Arkansas Valley of Colorado, high value vegetable crops can be produced successfully with different components of plasticulture. Overall yields, quality, and earliness of the crops are enhanced by using intensive production practices. Black plastic mulch in combination with drip irrigation has practical application for many types of crops including cantaloupe, watermelon, tomatoes, and peppers. Floating fabric and white-washed plastic row covers can further enhance the earliness of vegetable crops. Goal 2: Water quantity and quality can be managed with a well-designed drip irrigation system. Highly saline water can be used to grow high value vegetable crops without salts accumulating in the root zone. Fertilizer requirements are generally lessened when crops are drip-irrigated. Goal 3: High value colored sweet peppers can be grown in high tunnels that have some degree of shading (10-30%). Goal 4: Organic vegetable seed production is economically feasible in the Arkansas Valley of Colorado. Insect pests can be controlled with organic approved pesticides. Fertility needs can be met with manure composts. Weed control was manageable via mechanical cultivation and mulching with crop residues or black plastic mulches

Publications

• Type: Other Status: Accepted Year Published: 2015 Citation: June 2015, "Non-targeted metabolomics reveals phytochemical diversity in onion: implications for human health and disease prevention", American Society of Mass Spectrometry (ASMS), American Society of Mass Spectrometry, Chaparro, J. M. (Author & Presenter), Matthews, S. B., Bartolo, M. E., Thompson, H. J., Broeckling, C. D., Prenni, J. E., Heuberger, A., peer-reviewed/refereed.

Progress 10/01/13 to 09/30/14

Outputs
Target Audience: The target audience included vegetable growers, health care profesionals, NRCS field representatives, and private industry representatives. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Results from this project were presented at the National Allium Research Ceonference in Scottsdale, Arizona in December 2014 and the Colorado Onion Association meeting in January 2104. What do you plan to do during the next reporting period to accomplish the goals? Additional work will evaluate the effect of cultural and environmental factors on the phenolic content of onion varieties and the potential beneficial effects of onion consumption.

Impacts
What was accomplished under these goals? Onions have numerous health-related benefits that are increasingly linked to reductions in the incidence of non-communicable diseases such as diabetes, cancers, and heart disease. Onions contain highly active phytochemical compounds (thiosulfides and flavonoids) that are largely responsible for many of the aforementioned health-related benefits.Compared to other types of food, onions generally contain some of the highest levels of phytochemicals. It is known, however, that these health-promoting compounds can vary from one variety to the next. Onion variety trials are conducted annually in the major onion producing areas in the western United States. Some varieties evaluated in these trials constitute a significant proportion of the total amount of onions grown and consumed in the United States. Several widely-grown onion varieties were evaluated for their total phenolic content. Samples were taken from university-sponsored trials conducted in northern Colorado, southern Colorado, and the Columbia Basin of central Washington. Samples represented popular yellow, white, and red-skinned varieties. Across the geographical locations, the yellow-skinned variety “Granero” had the highest total phenolic content and the white-skinned variety “Cometa” had the lowest content. Two onion cultivars, the yellow-skinned variety “Vaquero” and the red-skinned variety “Redwing” were evaluated in an anti-cancer assay by altering the diet of genetically-modified laboratory mice. In an aggressive in vivo model for breast cancer, “Vaquero” had protective activity and “Redwing” had some, but significantly less activity. Additional work will evaluate the effect of cultural and environmental factors on the phenolic content of onion varieties and the potential beneficial effects of onion consumption.

Publications

• Type: Other Status: Accepted Year Published: 2014 Citation: Schwartz, H.F. ,D. Alston, J. Alwang, M. Bartolo , T. Blunt, C. Boateng, B. Bunn, C. Cramer, W. Cranshaw, J. Davidson, M. Derie, J. Doran, K. Douce, D. Drost, L. du Troit, J. Gao, T. Gourd, B. Gugino, B. Hammon, J. hardin, M. Hausbeck, G. Jibilian, J. Lafferty, J. LaForest, M. McMillan, K. Mohan, J. Morrice, B. Nault, C. Nischwitz, G. Norton, K. Otto, H. Pappu, M. Pettersen, R. Sampangi, B. Schroeder, W. Secor, S. Szostek, N. Tisserat, M. Uchanski, J. VanKirk, T. Waters P. Wiriyajitsomboon, C. Wholeb. 2013. Onion Health Management and Production. CSU IPM Center Bulletin. 2014. Onion ipmPIPE: A Coordinated Effort to Improve the Management of Onion Thrips and Iris yellow spot virus for the U.S. Onion Industry. Plant Health Progress, Vol. 15 No. 4 172-183. Bartolo, M.E., T. Gourd, T. Watters, C. Wholeb, Z. Zhu, W. Jeiquin, S. Matthews, and H. Thompson. 2014. Varietal Differences in Phenolic Content and Anti-Cancer Potential of Western Long-Day Onions. Proc. National Allium Research Conference, Scottsdale, Az.

Progress 01/01/13 to 09/30/13

Outputs
Target Audience: Vegetable Growers, Crop Consultants, NRCS Field Representatives, and Private Industry Representatives Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? These results have been disseminated via grower meetings and technical reports. What do you plan to do during the next reporting period to accomplish the goals? During the next reporting, additional work will be conducted on the efficacy of using plastic mulches and drip irigation for the production of hybrid pepper varieties.

Impacts
What was accomplished under these goals? Specialty-type peppers, including colored bells and other sweet types, are becoming increasingly popular in Colorado. These peppers typically command a high price relative to other pepper types and are usually marketed to the public via farmers markets or restaurants. Colorado’s production areas are at a relatively high elevation and receive high amounts of sunlight. The purpose of this experiment was to examine the effects of pepper yield and quality grown with 30% shade (black)cloth and a spun-bound polyester row cover relative to an uncovered control. Both the shade cloth and spun-bound polyester treatments significantly reduced the incidence of sunscald and dramatically improved marketable yield. In general, the 30% shade cloth was more difficult to install but required very little upkeep and maintenance during the course of the season. The spun-bound fabric was easier to install but required frequent maintenance due to movement by wind. Overall, this study illustrates that colored bell pepper and sweet pepper marketable yields can be improved in Colorado by treatments that reduced the incidence of solar radiation.

Publications

• Type: Other Status: Published Year Published: 2013 Citation: Schwartz, H.F. ,D. Alston, M.E. Bartolo , C. Cramer, W. Cranshaw, D. Drost, L. du Troit, B. Dutta, R. Gitaitis, J, Hardin, B. Nault, S. Nissen, H. Pappu, K. Reddin, B. Schroeder, R. Srinivasan, S. Szostek, M. Uchanski, T. Waters. 2013. Onion Health Management and Production. CSU IPM Center Bulletin. Johnson, J.J., S.D. Haley, M. Bartolo, K. Larson, J. Davidson, F. Peairs, N. Tisserat, P. Westra, J. Davis, D. Westfall, S. Sauer. 2013. Making Better Decisions, 2013 Colorado Winter Wheat Variety Performance Trials. Colorado State University Agric. Exp. Stn. Technical Report TR 13-09. Johnson, J.J., J. Hain, S. Sauer, M. Bartolo, J. Davidson, K. Jewell, 2013. Making Better Decisions, 2013 Colorado Corn Performance Trials. Colorado State University Agric. Exp. Stn. Technical Report TR 13-7. Johnson J. J., H.F Schwartz., M.A. Brick, K. Otto, J. Hain, M. Bartolo, A. Andales, S. Sauer, K. Jewell, B. Ogg, J. Davidson and M. McMillan. 2013. Making Better Decisions, 2013 Colorado Dry Bean Variety Performance. Colorado State University Agric. Exp. Stn. Technical Report TR 13-5. Johnson, J.J., J. Hain, S. Sauer, M. Brick, H.Schwartz,, P. Cabot, M. Bartolo, J. Davidson, K. Larson, and K. Jewell. 2013. Colorado spring crop variety performance trials. High Plains Journal. January 2013.

Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Chile peppers are an important specialty crop in the Arkansas Valley of Colorado. Most the peppers grown in this region are direct seeded into bare ground and irrigated via gravity-flow furrows. Problems with the cost and availability of labor for thinning, hoeing, and harvesting have made chile pepper production more challenging with conventional production methods. A general lack of irrigation water is yet another issue that has hindered traditional pepper production methods. In previous studies, it was determined that total water applications to a chile pepper crop via gravity-flow furrows can exceed 72 acre-inches per season. Intensive production methods employing drip irrigation and plastic mulch are potential ways to addresses the aforementioned issues. The purpose of this experiment was to examine the water use and horticultural characteristics of different chile pepper varieties that were direct-seeded or transplanted into plastic mulch and irrigated with drip tubing. Overall, the seasonal consumptive use of irrigation water was 17.7 acre-inches. Direct-seeding into plastic mulch resulted in significant and commercially unacceptable stand losses. Transplanting into plastic much was successful for all varieties. When transplanted, several new hybrid chile pepper varieties, most notably Anaheim 118, had yields that exceeded those of commonly used open-pollinated varieties. However, the fruit of transplanted peppers were generally of less quality than those of direct-seeded peppers as measured by pod size and pod straightness. This study illustrates that chile pepper yield can be enhanced by transplanting improved varieties and using plasticulture practices that reduce the need for hand labor and reduce the consumptive use of water. PARTICIPANTS: Individuals that contributed to the project included Colorado State University Agricultural Experiment Station personnel, Lee Sommers, Frank Johnson, Jeff Davidson, Kevin Tanabe, and research technicians TARGET AUDIENCES: The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Chile peppers are an important specialty crop in the Arkansas Valley of Colorado. Plasticulture components employing drip irrigation and plastic mulch can dramatically improve fresh market yield of numerous crops. Gross returns from chile peppers grown for the fresh market have the potential to reach $10,000 per acre. These studies suggest that transplanting hybrid chile pepper varieties into black plastic mulch and providing irrigation water via drip tubing can reduce water use, increase fresh market yield, and reduce the need for some labor intensive production practices.

Publications

• Bartolo, M.E. 2012. Onion Variety Trial-2009. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.8-10.
• Bartolo, M.E. 2012. Effect of Water Quality on Cantaloupe Yield and Quality. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.14-17.
• Bartolo, M.E. 2012. Effect of Water Quality on Watermelon Yield and Quality. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.18-21.
• Bartolo, M.E. 2012. Organic Seed Production Trial. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.22-24.
• Bartolo, M.E. 2012. Cantaloupe Foliar Nutrient and Growth Regulator Trial. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.14-17.
• Cranshaw, W. and Bartolo, M.E. 2012. Onion Thrips Tolerance Trial. In Arkansas Valley Research Center 2009 Reports, CSU Ag. Expt. Station Technical Report 12-5. p.11-13.
• Johnson J. J., H.F Schwartz., M.A. Brick, K. Otto, J. Hain, M. Bartolo, A. Andales, S. Sauer, K. Jewell, B. Ogg, J. Davidson and M. McMillan. 2012. Making Better Decisions, 2012 Colorado Dry Bean Variety Performance. Colorado State University Agric. Exp. Stn. Technical Report TR 12-12. November 2012.

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: Chile peppers are an important specialty crop in the Arkansas Valley of Colorado. Most the peppers grown in this region are direct seeded into bare ground and irrigated via gravity-flow furrows. Problems with the cost and availability of labor for thinning, hoeing, and harvesting have made chile pepper production more challenging with conventional production methods. Transplanting alone, rather than direct seeding peppers, into a conventional production system can reduce the need for thinning and hoeing. However, transplanted chile peppers often have inferior pod characteristics compared to peppers that were direct-seeded. Plastic mulches can also reduce the need for some labor associated with weed control. The purpose of this experiment was to examine the horticultural characteristics of different chile pepper varieties that were direct-seeded or transplanted into plastic mulch and irrigated with drip tubing. Overall, direct seeding chile peppers into plastic mulch resulted in significant and commercially unacceptable stand losses (50-70%). Transplanting into plastic much was successful for all varieties. When transplanted, several new hybrid chile pepper varieties had yields that exceed those of commonly used open-pollinated varieties. Those same transplanted varieties had excellent quality as measured by pod size and pod straightness. This study illustrates that chile pepper yield and quality can be enhanced by transplanting improved varieties and using plasticulture practices that reduce the need for hand labor. PARTICIPANTS: Individuals that contributed to the project included Colorado State University Agricultural Experiment Station personnel, Lee Sommers, Frank Johnson, Jeff Davidson, Kevin Tanabe, and research technicians TARGET AUDIENCES: The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Chile peppers are an important specialty crop in the Arkansas Valley of Colorado. Plasticulture components employing drip irrigation and plastic mulch can dramatically improve fresh market yield of chile peppers. Gross returns from chile peppers grown for the fresh market have the potential to reach $10,000 per acre. These studies suggest that transplanting hybrid chile pepper varieties into black plastic mulch can increase fresh market yield and quality and reduce the need for some labor intensive production practices

Publications

• Chavez, J.L., T.A. Howell, D. Straw, P.H. Gowda, L.A. Garcia, S. Evett, T. Ley, L. Simmons, M. Bartolo, P. Colaizzi, and A. Andales. 2010. Surface Aerodynamic Temperature Derived from Wind/Temperature Profile Measurements over Cotton and Alfalafa in a Semi-Arid Environment. Proceedings of the 2010 World & Water Congress, EWRI-ASCE, pp. 2090-2101, Reston, VA: ASCE
• Chavez, J.L., D. Straw, L. A. Garcia, T. W. Ley, A. A. Andales, L. H. Simmons, and M. E. Bartolo. 2010. Mapping ET in Southeastern Colorado Using a Surface Aerodynamic Temperature Model. Proceedings of the 2010 U.S. Commission on Irrigation and Drainage (USCID), Meeting Irrigation Demands in a Water-Challenged Environment. CD-ROM, pp. 297-308, September 28 - October 1, Fort Collins, CO.
• AlWahaibi, H., A. Andales, D. Straw, L. Simmons, M. Bartolo, T. Ley, T. Trout, J. Chavez, and N. Hansen. 2010. Alfalfa Crop Coefficients Developed Using a Weighing Lysimeter in Southeast Colorado. Proc.(USCID), Meeting Irrigation Demands in a Water-Challenged Environment, CD-ROM, pp. 309-317, September 29 - October 1, Fort Collins, CO.
• Chavez, J.L., Straw D., Garcia L.A., Ley T.W., Andales, A.A., Simmons L., Bartolo M.E., and Neale C.M.U. 2010. Remote sensing ET of alfalfa using a surface aerodynamic temperature model. In Proceeding of the 5th National Decennial Irrigation Conference, ASABE, Irrigation Association, Paper No. IRR10-8513, St. Joseph, Mich: ASABE
• Andales A.A., Simmons L.H., Bartolo M.E., Straw D., Chavez J.L., Ley T.W., and AlWahaibi H.S. 2010. Alfalfa ET from a weighing lysimeter in the Arkansas Valley of Colorado. In Proceedings of the 5th National Decennial Irrigation Conference, ASABE & IA, Phoenix, AZ.

Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: The Arkansas Valley has a long and successful history of vegetable seed production and at one time, provided a significant portion of the cucurbit seeds used in the United States. Although seed production has diminished from its historically high level, there is still a sizable amount of conventional seed production in the Valley. In recent years, there has been a dramatic increase in organic vegetable production. As a result, demand for organic vegetable seed is growing rapidly as the USDA National Organic Program requires organic farmers to use certified organic seed when available. With this potential, there may be an opportunity to re-establish the seed production industry in the Arkansas Valley. In 2010, a study was conducted to characterize the fresh market and seed yield response of organically-grown watermelon (Crimson Sweet) to different mulching methods. The methods were bare ground, straw mulch, and black plastic mulch. All treatments were irrigated via drip lines placed under the production bed at a depth of 3 inches. Total marketable fruit yields and seed yields were significantly higher for watermelon grown with black plastic mulch than with straw mulch or with bare ground. The straw mulch treatment had higher fresh fruit yield and seed yield than bare ground but that difference was not significant (lsd=0.1). Relative to the other treatments, weeds were easier to control in the plastic mulch treatment. This study suggests that organically-grown watermelon fruit and seed can be successfully produced in the Arkansas Valley. Mulching with black plastic enhances fresh market fruit yield and seed yield and improves weed control. PARTICIPANTS: Individuals that contributed to the project included Colorado State University Agricultural Experiment Station personnel, Lee Sommers, Frank Johnson, Jeff Davidson, Kevin Tanabe, and research technicians TARGET AUDIENCES: The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The Arkansas Valley has a long and successful history of vegetable seed production and at one time, provided a significant portion of the cucurbit seeds used in the United States. The high demand for organically-grow seed creates a renewed marketing opportunity for Valley growers. Plasticulture can dramatically improve fresh market yield and seed yield of organically-grown watermelon. Gross returns without plasticulture average $3000 per acre. With plasticulture, gross returns reach $6000 per acre with approximately $200 additional cost for plastic or a net marginal income increase of $2800 per acre.

Publications

• Bartolo, M.E. 2010. Pepper Foliar Nutrient and Growth Regulator Trial. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.43-44.
• Bartolo, M.E. 2010. Onion variety trial. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.16-18.
• Schwartz, H.F. and Bartolo, M.E. 2010. Onion disease trials. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.19-20.
• Cranshaw, W. and Bartolo, M.E. 2010. Onion thrips tolerance and insecticide trials. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.22-30.
• Bartolo, M.E. 2010. Effect of Water Quality on Cantaloupe Yield and Quality. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.31-34.
• Bartolo, M.E. 2010. Effect of Water Quality on Watermelon Yield and Quality. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.35-38.
• Halvorson, A.D. and Bartolo, M.E. 2010. Chile Pepper Response to Nitrogen Fertilization. In Arkansas Valley Research Center 2008 Reports, CSU Ag. Expt. Station Technical Report 10-13. p.39-42.

Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Watermelons and muskmelons are important fresh market crops in the Arkansas Valley of Colorado. Growers are increasingly using drip irrigation to produce these crops as a means to improve overall production. Concurrent with the conversion to drip irrigation, growers have switched to ground water for irrigation instead of the traditional surface water sources. Ground water is temporally more reliable than surface water and is relative free of particulates. Both characteristics make ground water more amenable for use in drip systems. Unfortunately, ground water sources contain 2 to 3 times the amount of soluble salts than surface waters. In 2008 and 2009, studies were conducted to characterize the response of commonly grown watermelon (Stars and Stripes) and muskmelon (Athena) cultivars to irrigation waters having an electrical conductivity (EC) of 1.0 ds.m-1 (low EC surface water) or 2.8 ds.m-1 (high EC ground water). The timing and amounts of irrigations were the same for both water treatments throughout the two growing seasons and all irrigations were delivered via a drip system. In both years, total marketable yields were not significantly different when both watermelon and muskmelon were irrigated with ground or surface water. Similarly, fruit size and fruit number were unaffected by irrigation water source. Further, watermelon quality, as measured by percent brix, was not influenced by irrigation water salinity. In 2008, the percent brix of muskmelon irrigated with ground water was significantly higher (0.69 percent) than those irrigated with the lower salinity surface water. In 2009, muskmelon quality (% brix) was not influenced by irrigation water salinity. These studies suggest that watermelon and muskmelon response to relatively saline irrigation water in the Arkansas Valley of Colorado may not be as detrimental as that predicted by other studies; i.e. studies conducted with waters more influenced by the presence of sodium salts. PARTICIPANTS: Individuals that contributed to the project included Colorado State University Agricultural Experiment Station personnel, Lee Sommers, Frank Johnson, Kevin Tanabe, and research technicians. TARGET AUDIENCES: The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Watermelon and muskmelon, produced on approximately 2000 acres, are some of the most profitable and intensively managed crops in the Arkansas Valley of Colorado. Drip irrigation used along with the other forms of plasticulture, can double yields and improve gross returns by $3000-4000 per acre. As growers adopt more intensive production practices, they are finding that, although higher in salt content, ground water is functionally easier to use in drip systems than traditionally-used surface water sources. These studies suggest that growing drip-irrigated watermelon and muskmelon with relatively saline ground water does not significantly alter yields. Overall, growers using ground water in drip irrigation systems may be able to maintain yields, manage salinity in the soil profile, and in some cases, improve melon quality.

Publications

• Halvorson, A.D.,Bartolo, M.E., Reule, C.A.,Berrada, A. 2009. Nitrogen Effects on Onion Yield Under Drip and Furrow Irrigation. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 09-12. p.16-34.
• Bartolo, M.E. 2009. Onion variety trial-2007. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 09-12. p.35-37.
• Bartolo, M.E. 2009. Onion response to different water qualities. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 09-12. p.38-41.
• Bartolo, M.E. 2009. Sweet onion production from transplants. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 09-12. p.42-43.
• Bartolo, M.E. and Cranshaw, W. 2009. Tomato virus control trial. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 09-12. p.44-45.
• Bartolo, M.E. 2009. Paper mulches for vegeyable production. In Arkansas Valley Research Center 2007 Reports, CSU Ag. Expt. Station Technical Report 46-47.

Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Watermelons and muskmelons are important fresh market crops in the Arkansas Valley of Colorado. Growers are increasingly using drip irrigation to produce these crops as a means to improve overall production. Concurrent with the conversion to drip irrigation, growers have switched to ground water for irrigation instead of the traditional surface water sources. Ground water is temporally more reliable than surface water and is relative free of particulates. Both characteristics make ground water more amenable for use in drip systems. Unfortunately, ground water sources contain 2 to 3 times the amount of soluble salts than surface waters. In 2008, a study was conducted to characterize the response of commonly grown watermelon (Stars and Stripes) and muskmelon (Athena) cultivars to irrigation waters having an electrical conductivity (EC) of 1.0 ds.m-1 (low EC surface water) or 2.8 ds.m-1 (high EC ground water). The timing and amounts of irrigations were the same for both water treatments throughout the growing season and all irrigations were delivered via a drip system. Total marketable yields were not significantly different when both watermelon and muskmelon were irrigated with ground or surface water. Similarly, fruit size and fruit number were unaffected by irrigation water source. Further, watermelon quality, as measured by percent brix, was not influenced by irrigation water salinity. In contrast, the percent brix of muskmelon irrigated with ground water was significantly higher (0.69 percent) than those irrigated with the lower salinity surface water. These studies suggest that watermelon and muskmelon response to relatively saline irrigation water in the Arkansas Valley of Colorado may not be as detrimental as that predicted by other studies; studies conducted with waters more influenced by the presence of sodium salts. PARTICIPANTS: Individuals that contributed to the project included Colorado State University Agricultural Experiment Station (CSU-AES) personnel, Dr. Lee Sommers and Dr. Frank Johnson who provided financial support and established the Salinity Initiative Project in the Arkansas Valley. Also, CSU-AES personnel Kevin Tanabe and research technicians who supplied labor and technical support. TARGET AUDIENCES: The target audience included vegetable growers, crop consultants, NRCS field representatives, and private irrigation industry representatives. Educational efforts included field exhibitions and grower meetings. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Watermelon and muskmelon, produced on approximately 2000 acres, are some of the most profitable and intensively managed crops in the Arkansas Valley of Colorado. Drip irrigation used along with the other forms of plasticulture, can double yields and improve gross returns by $3000-4000 per acre. As growers adopt more intensive production practices, they are finding that, although higher in salt content, ground water is functionally easier to use in drip systems than the traditionally-used surface water sources. These studies suggest that growing drip-irrigated watermelon and muskmelon with relatively saline ground water does not significantly alter yields. Overall, growers using ground water in drip irrigation systems may be able to maintain yields, manage salinity in the soil profile, and in some cases, improve melon quality.

Publications

• Halvorson, A.D.,Bartolo, M.E., Reule, C.A.,Berrada, A. 2008. Nitrogen effects on onion yield under drip and furrow irrigation. Agron. J. 2008 100: 1062-1069.
• Halvorson, A.D.,Bartolo, M.E., Reule, C.A.,Berrada, A. 2008. Onion response to nitrogen and irrigation type following soybeans in 2006. In Arkansas Valley Research Center 2006 Reports, CSU Ag. Expt. Station Technical Report 08-14. p.19-22
• Bartolo, M.E. 2008. Onion variety trial-2006. In Arkansas Valley Research Center 2006 Reports, CSU Ag. Expt. Station Technical Report 08-14. p.23-25.
• Bartolo, M.E. 2008. Onion response to different water qualities. In Arkansas Valley Research Center 2006 Reports, CSU Ag. Expt. Station Technical Report 08-14. p.26-30.
• Bartolo, M.E. and Cranshaw, W. 2008. Tomato virus control trial. In Arkansas Valley Research Center 2006 Reports, CSU Ag. Expt. Station Technical Report 08-14. p.32-33.
• Bartolo, M.E. 2008. Pepper growth regulator trial. In Arkansas Valley Research Center 2006 Reports, CSU Ag. Expt. Station Technical Report 08-14. p.34-35`.

Progress 01/01/07 to 12/31/07

Outputs
Onions are one of the highest value and most-widely grown crops in Colorado. Onions are also one of the most salt sensitive crops and are susceptible to water deficits due to the shallow nature of their root system. In many rapidly urbanizing western states, the competition for water resources is dramatically increasing. Some growers are now using water sources that have lower quality than direct-flow sources from streams and rivers. In 2007, a study was conducted to characterize the response of four commonly grown onion cultivars (Ranchero, X-202, Cometa, and Redbull) to irrigation waters having an electrical conductivity (EC) of 1.0 ds.m-1 (low EC river water) or 2.8 ds.m-1 (high EC groundwater). The timing and amounts of irrigations were the same for both water treatments throughout the growing season and all irrigations were delivered via a drip system. Total marketable yields were lowered significantly for all varieties when irrigated with the high EC water. The yellow varieties, Ranchero and X-202 had a 16.7% and 17.7% decrease in total marketable yield, respectively, when irrigated with the high EC water. The white (Cometa) and red (Redbull) varieties had a 7.7% and 23.9% decrease in total marketable yield, respectively, when irrigated with the high EC water. For all varieties, the proportion of jumbo class onions (>3 in diameter) was significantly reduced. As a result, economic losses were realized for all onion varieties when irrigated with the higher EC water. Despite these findings, onion response to high salinity in the Arkansas Valley of Colorado may not be as severe as those predicted by other studies; studies conducted with soils and waters more influenced by the presence of sodium salts. As a result, growers using groundwater may be able to manage salinity by choosing varieties that are more tolerant of salinity and irrigating with a sufficient volume of water to prevent excessive build-up of salt in the soil profile.

Impacts
Onions are one of the most profitable and intensively managed crops for Colorado growers. In many western states, water shortages have caused growers to use alternative water sources like groundwater that have lower quality than surface waters. Growers using groundwater may be able to successfully manage salinity by choosing varieties that are more tolerant of salinity and irrigating with a sufficient volume of water to prevent excessive build-up of salt in the soil profile.

Publications

• BARTOLO, M.E. 2007. Onion Varity Trial-2004. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.26-28.
• BARTOLO, M.E. 2007. Onion Varity Trial-2005. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.29-31.
• BARTOLO, M.E. 2007. Onion Spacing and Drip Irrigation Trial-2004. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.32-33.
• BARTOLO, M.E. 2007. Onion Micronutrient Trial-2005. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.54-55`.
• BARTOLO, M.E. 2007. Mira Sol Pepper Variety Development. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.63-64.
• HALVORSON, A.D., BARTOLO, M., REULE, C.A. 2007. Chile Pepper Response to Nitrogen Fertilization in Colorado s Arkansas Valley. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.65-68.
• BARTOLO, M.E. 2007. Bell Pepper Quality Trial. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.69-71.
• BARTOLO, M.E. 2007. Early Cantaloupe Production Trial. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.72-74.
• BARTOLO, M.E. and CRANSHAW, W. 2007. Tomato Virus Control. In Arkansas Valley Research Center 2004-05 Reports, CSU Ag. Expt. Station Technical Report 07-14. p.75-76.

Progress 01/01/06 to 12/31/06

Outputs
Onions are one of the highest value and most-widely grown crops in Colorado. Onions are also one of the most salt sensitive crops and are susceptible to water deficits due to the shallow nature of their root system. In many rapidly urbanizing western states, the competition for water resources is dramatically increasing. Growers are having to use alternative water sources that often have lower quality than the sources they have historically used from streams and rivers. In 2006, a study was conducted to characterize the response of three commonly grown onion cultivars (Ranchero, Cometa, and Redbull) to irrigation waters having an electrical conductivity (EC) of 1.0 ds.m-1 (low EC river water) or 2.8 ds.m-1 (high EC groundwater). The timing and amounts of irrigations were the same for both water treatments throughout the growing season and all irrigations were delivered via a drip system. Total marketable yield was lowered slightly (3.5%) but not significantly, when the yellow variety, Ranchero, was irrigated with the high EC water. The white (Cometa) and red (Redbull) varieties had a 19.8% and 19.2% decrease in total marketable yield, respectively, when irrigated with the high EC water. For all varieties, the proportion of jumbo class onions (>3 in diameter) was significantly reduced. As a result, economic losses were realized for all onion varieties when irrigated with the higher EC water. Nonetheless, onion response to high salinity in the Arkansas Valley of Colorado may not be as severe as those predicted by other studies; i.e. studies conducted with soils and waters more influenced by the presence of sodium salts. As a result, growers using groundwater may be able to manage salinity by choosing varieties that are more tolerant of salinity and irrigating with a sufficient volume of water to prevent excessive build-up of salt in the soil profile.

Impacts
Onions are one of the most profitable and intensively managed crops for Colorado growers. In many western states, water shortages have caused growers to use alternative water sources like groundwater that have lower quality than surface waters. Growers using groundwater may be able to successfully manage salinity by choosing varieties that are more tolerant of salinity and irrigating with a sufficient volume of water to prevent excessive build-up of salt in the soil profile.

Publications

• HALVORSON, A.D., BARTOLO, M., REULE, C.A., BERRADA, A. 2006. Onion Response to mitrogen fertilization under drip and furrow irrigation. Proceedings National Allium Research Conference. December 7-8, 2006, College Station, TX p. 73-78.
• HALVORSON, A.D., BARTOLO, M., REULE, C.A., BERRADA, A. 2006. Onion response to nitrogen fertilization under drip and furrow irrigation. Proceedings of Great Plains Soil Fertility Conference. Denver, CO, March 7-8, 2006. Kansas State University, Manhattan, Potash and Phosphate Institute. Brookings, SD. 11:7-12.
• HALVORSON, A.D., BARTOLO, M., REULE, C.A., BERRADA, A. 2006. Drip versus furrow irrigation for onion production in the Colorado Lower Arkansas River Valley. Soil and Water Conservation Society. Abstract. July 22-26-2006, Keystone, CO. J. Soil and Water Conserv. 61(3):229.
• BARTOLO, M.E. 2006. Onion response to different water qualities delivered via drip irrigation. Proceedings National Allium Research Conference. Abstract. December 7-8, 2006, College Station, TX p. 46.
• BERRADA, A., HALVORSON, A.D., BARTOLO, M., VALLIANT, J. 2006. The effect of subsurface drip and furrow irrigation on the movement of salts and nitrate in the root zone. Irrigation Associations Exposition and Technical Conference Proceedings. P. 1-13.

Progress 01/01/05 to 12/31/05

Outputs
Onion is a high cash value crop that is commonly fertilized with high N rates to maximize yield. In addition, the shallow-rooted onion requires frequent irrigations. In 2005, six N rates were applied (0, 45, 90, 135, 180, and 225 kg N/ha) to existing N plots previously cropped to corn (2000-2003) and chile pepper (2004). The N source was a polycoated urea with a 90 to 120 day release period which was applied prior to planting. The N main plots were split to allow irrigation by furrow (normal method) and by a drip system. At the end of the season, a total of 68 cm of irrigation water had been applied with the drip system and 244 cm with the furrow system. In the furrow-irrigated treatment, 127 cm ran off the end of the field for a net application of 117 cm. Total marketable fresh onion yield increased with increasing N rate in both systems, with less response of onion to N with the drip system compared to the furrow irrigation system. Significantly higher onion yields were obtained with the drip system. The percentage of the onion crop that was of colossal size (> 10 cm diameter) increased from 5% to 14% with increasing N rate, jumbo size (7.5-10 cm diameter) which made up 80% of the yield was not affected by N rate, and medium size (5-7.5 cm diameter) decreased from 14% to 5% with increasing N rate. Adjusted gross economic returns were greater with drip irrigation than with furrow irrigation. This work demonstrates that economic returns can be maintained by using the more efficient drip irrigation system for onion production rather than the inefficient furrow irrigation system. With the drip system, onion yields were maximized with a lower rate of N fertilizer and 72% less irrigation water than with the furrow irrigation system.

Impacts
Onions are one of the most profitable and intensively managed crops for Colorado growers. In Colorado and other western states, water shortages have caused growers to examine more efficient methods of irrigation. Onion yields were maximized with drip irrigation using 72% less water and less nitrogen fertilizer than furrow irrigation. Overall, adjusted gross economic returns were greater with drip irrigation than with furrow irrigation.

Publications

• Halvorsen, A.D., Schweissing, F.C., Bartolo, M.E., and Reule, C.A. 2005. Corn Response to Nitrogen Fertilization in a Soil with High Residual Nitrogen. Agron. J. 97:1222-1229.

Progress 01/01/04 to 12/31/04

Outputs
In the Arkansas Valley of Colorado, watermelons, a major vegetable crop, are increasingly being produced using black plastic mulch and subsurface drip irrigation. Plastic mulch has many proven attributes including increased yield and accelerated crop development. Unfortunately, plastic mulch is expensive and requires a significant amount of labor for application and removal from the field. Disposal of the used mulch in landfills or via incineration is also problematic. As a means to maintain watermelon productivity and reduce production costs, experiments were conducted to evaluate alternative mulching methods. A seeded and seedless watermelon varieties were transplanted or direct seeded into straw mulch, soybean residue, bare ground or plastic mulch. Differences in yield and earliness among the different methods were examined. Transplanting or direct-seeding seeded watermelon and transplanting seedless watermelon into soybean residue, bare ground, or plastic mulch produced yields that were statistically similar. Overall, transplanting was the superior method of establishment for seedless watermelon in any mulch type. Yields for both melon types grown in straw mulch were consistently the lowest, largely due to competition from volunteer wheat late in the growing season. For both melon types, earliness was enhanced by transplanting into plastic mulch. In most instances the advantage was only 3-4 days over direct-seeding or transplanting into the other mulches.

Impacts
Watermelon is one of the most profitable crops for Southern Colorado growers. Direct seeding or transplanting watermelon into bare ground or an existing crop residue may reduced the need for using costly plastic mulch. Plastic mulches can increase the cost of production by approximately $625 per hectare.

Publications

• BARTOLO, M.E. and SCHWEISSING F.C. 2004. Onion variety trial. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7 p.24-26.
• BARTOLO, M.E. 2004. Seedless Watermelon Establishment. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7. p.43-44.
• BARTOLO, M.E. 2004. Melon Foliar Fertilizer Trials. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7. p.45-46.
• BARTOLO, M.E. 2004. Pepper Stand Reduction Trial. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7. p.47-48.
• BARTOLO, M.E. 2004. Pepper Soil Crusting Trial. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7. p.49-50.
• HALVORSEN, A.D., BARTOLO, M.E. and REULE, C.A. 2004. Nitrogen Requirements of Irrigated Corn in Colorado s Arkansas Valley. In 2003 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR04-7 p.11-16.

Progress 01/01/03 to 12/31/03

Outputs
In the Arkansas Valley of Colorado, seedless watermelons are an increasingly important crop and have surpassed seeded watermelons in terms of acreage and value. Seedless watermelons are relatively expensive to grow. Seedless watermelon seed, in particular, is extremely expensive and difficult to germinate. As a result, seedlings are often started in the greenhouse and later transplanted into the field. Seedless watermelons are also grown with plastic mulch and drip irrigation, further adding to the cost of production. As a means to improve productivity and reduce production costs, experiments were conducted to evaluate different methods of stand establishment. Transplanting and direct seeding into clear, green, and black plastic mulch were examined. Transplanting into all three colored mulches resulted in 100% stands and yields that were statistically similar. Direct seeding into black, green, and clear mulch resulted in stands of 50%, 57%, and 59% respectively. After planting in early May, average soil temperatures were greatest under clear mulch:26.1C(79F), followed by green mulch:22.8C(73F) and black mulch:21.7C(71F). Overall, marketable yields were lowest when watermelons were direct seeded into black plastic mulch. Direct seeding into green mulch resulted in slightly higher yields and direct seeding into clear mulch gave rise to marketable yields that were comparable to the transplanted treatments.

Impacts
Seedless watermelon are one of the most profitable crops grown in Southern Colorado. Direct seeding into clear or light transmitting plastic mulches may reduced the need for transplanting. Direct seeding can reduce the cost of production by approximately $740/ha ($300 per acre).

Publications

• BARTOLO, M.E. 2003. Tomato spacing trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.79-80.
• TABOR H.G., BARTOLO, M.E. and LAWSON V. 2003. Foliar boron application to filed grown tomatoes. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.81-85.
• BARTOLO, M.E. 2003. Watermelon establishment trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.86-87.
• BARTOLO, M.E. 2003. Seedless watermelon trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.88-89.
• BARTOLO, M.E. and SCHWEISSING F.C. 2003. Onion variety trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8 p.41-43.
• DOSS, O.C., BARTOLO, M.E., DAVIS J.G,, and CARDON G.E. 2003. Interactions between salinity and onion production practices in the Arkansas Valley, Colorado. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8 p.44-51.
• BARTOLO, M.E. 2003. Pepper stand reduction trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8 p.75-76.
• BARTOLO, M.E. 2003. Early cantaloupe trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.68-70.
• BARTOLO, M.E. 2003. Hybrid chile establishment. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8 p.71-72.
• BARTOLO, M.E. 2003. Jalapeno establishment trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8 p.73-74.
• BARTOLO, M.E. 2003. Pumpkin variety trial. In 2002 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR03-8. p.77-78.
• BARTOLO, M.E. 2002. Zinnia stand loss trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.90-92.

Progress 01/01/02 to 12/31/02

Outputs
In the Arkansas Valley of Colorado, onions are often grown in areas with saline soils and low quality irrigation water. Variety, irrigation, and fertility experiments were conducted to evaluate the interaction between onion production practices and soil salinity. The first experiment investigated three rates of magnesium sulfate applied to five onion varieties. The second experiment compared the impact of furrow and drip irrigation on onion yield and salt distribution in the soil profile and the third trial examined how different conventional and slow-release fertilizers influence salt distribution in the soil profile. Overall, there was not a significant difference in yield (p < 0.05) when onions were subjected to different levels of soil salinity. However, there was a tendency for the variety 'Vision' (Seminis Seeds) to be the most sensitive to increases in soil salinity and 'Redwing' (Bejo Seeds) to be the least sensitive as measured by total marketable yield. These same tendencies were observed in growth chamber experiments. Specifically, 'Vision' had the largest decrease in root and shoot weight and 'Redwing' the least when grown in a modified Hoagland's solution augmented with salts to three conductivity levels. In the irrigation experiment, drip irrigation gave rise to higher electrical conductivity (ECe) in the furrow and lower ECe in the middle of the double-row bed. Furrow irrigation gave rise to a salt distribution pattern inverse of the drip irrigation results. The highest salt concentrations were recorded in the center of the bed in the furrow-irrigated treatment. The drip-irrigated treatment received less than 19% of the water applied to the furrow-irrigated treatment. Different levels and types of nitrogen fertilizers did not have a significant effect on salt distribution in the soil profile or onion yield.

Impacts
The use of relatively salt-tolerant onion varieties may help improve onion production in the Arkansas Valley. Drip-irrigation can dramatically reduce the amount of water used in onion production. Optimally placed drip lines may help better manage salt distribution in the soil profile.

Publications

• HALVORSON, A.D., FOLLETT, R.F., BARTOLO, M.E., and SCHWEISSING, F.C. 2002. Nitrogen fertilizer use efficiency of furrow-irrigated onion and corn. Agron. J. 94:442-449.
• BARTOLO, M.E. and SCHWEISSING F.C. 2002. Onion variety trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.48-50.
• BARTOLO, M.E. and SCHWEISSING F.C. 2002. Onion fertility trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.51-50.
• BARTOLO, M.E. 2002. Early cantaloupe trials. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8. p.67-69.
• BARTOLO, M.E. 2002. Hybrid chile establishment trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.70-72.
• BARTOLO, M.E. 2002. Jalapeno establishment trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.73-74.
• BARTOLO, M.E. 2002. Bell pepper production trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.75-76.
• BARTOLO, M.E. 2002. Mira sol chile trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8. p.77-78.
• BARTOLO, M.E. 2002. Spinach hail damage trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.79-80.
• BARTOLO, M.E. 2002. Sweet corn variety trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8. p.81-82.
• BARTOLO, M.E. 2002. Tomato spacing trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8. p.83-84.
• BARTOLO, M.E. 2002. Watermelon establishment trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8. p.85-86.
• BARTOLO, M.E. 2002. Zinnia stand loss trial. In 2001 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR02-8 p.87-89.

Progress 01/01/01 to 12/31/01

Outputs
Peppers are one of the most profitable fresh market and processed crops produced in the Arkansas Valley of Colorado. Most commercially used varieties are open-pollinated and established by direct seeding. Many new and productive hybrid varieties are currently available to growers. However, the high cost of hybrid seed makes direct seeding uneconomical. Transplanting may help reduce the seed cost and maximize the productivity of hybrid chile peppers. This study was conducted to determine how different methods of crop establishment affect the yield and pod characteristics of a hybrid long green chile, "Navojoa", and a hybrid jalapeno, "Grande" (both Seminis Vegetable Seeds). Direct seeding was compared to transplanting different sized peppers at different in-row spacings in a furrow-irrigated production system. Direct-seeded long green chile and jalapenos produced fruit that were high yielding and of good quality. Transplants grown in plastic trays containing 75, 200, or 288 cells and transplanted at in-row spacings of 15, 22, or 30cm all produced excellent stands and comparable yields to direct-seeded peppers. However, the pods on all transplanted long green chile peppers were shorter and more curved than the pods on direct-seeded peppers. For jalapenos, there was not a noticeable difference in fruit characteristics between the treatments. The closest(15cm) in-row spacing, however, produced jalapeno fruit that were significantly smaller (average fruit weight) than the other treatments. For both long green chile and jalapenos, transplanted peppers plants were consistently shorter than direct-seeded plants and, as a result, the fruit had a tendency to touch or be closer to the soil surface.

Impacts
The use of hybrid chile varieties can significantly increase the yield of fresh market and processed peppers. Transplanting can help reduce the seed costs associated with using hybrid pepper varieties.

Publications

• BARTOLO, M.E. 2001. Bell pepper production trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9 p.67-68.
• BARTOLO, M.E. 2001. Spinach hail damage trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.69-70.
• BARTOLO, M.E. 2001. Hybrid chile establishment trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9 p.63-64.
• BARTOLO, M.E. 2001. Jalapeno establishment trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9 p.65-66.
• BARTOLO, M.E. and SCHWEISSING F.C. 2001. Onion variety trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9 p.34-36.
• BARTOLO, M.E. 2001. Early cantaloupe trials. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.55-57.
• BARTOLO, M.E. 2001. Carrot Disease Trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.58-59.
• BARTOLO, M.E. 2001. Pepper variety trials. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.60-62.
• BARTOLO, M.E. 2001. Tomato production trials. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.71-77.
• BARTOLO, M.E. 2001. Early watermelon trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.78-79.
• BARTOLO, M.E. 2001. Transplanted versus seeded watermelon. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9. p.80.
• BARTOLO, M.E. 2001. Zinnia stand loss trial. In 2000 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR01-9 p.81-83.

Progress 01/01/00 to 12/31/00

Outputs
Peppers are one of the most profitable fresh market commodities sold thru road-side stands and other direct-markets. Despite their high productivity, hybrid chile varieties are rarely used in commercial operations in Colorado. Most chile is direct-seeded; therefore, it is not considered economical to use costly hybrid varieties. As more growers adopt intensive production practices, transplanting or seeding into plastic mulch may help reduce the seed cost and maximize the productivity of hybrid chile peppers. This study was conducted to determine how different methods of crop establishment affect the yield and pod characteristics of a hybrid long green chile, `Navojoa' (Petoseeds). Direct seeding was compared to transplanting different sized peppers into plastic mulch. Direct seeding through plastic mulch did not result in an acceptable stand. Although seed germination was excellent, the young seedlings were prone to wind damage at the soil line. About 50% of the stand was lost with direct-seeding. Transplants grown in plastic trays containing 75, 200, or 288 cells all produced excellent stands and yields. There was not a significant difference in marketable yield between the different-sized transplants. However, the larger (75 cell) transplants matured earlier than the smaller transplant sizes. Pod quality was highest on direct-seeded peppers. The pods on transplanted peppers were shorter and more curved than the pods on direct-seeded peppers. Generally, the larger transplants gave rise to the highest percentage of curved pods. In addition, transplanted pepper plants were consistently shorter than direct-seeded plants and, as a result, the pods had a tendency to touch the ground.

Impacts
The use of hybrid chile varieties as compared to open pollenated varieties can significantly increase the yield of fresh market peppers with an estimated increase in gross income of $3,000-$4,000 per hectare.

Publications

• BARTOLO, M.E. and SCHWEISSING F.C. 2000. Onion variety trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7 p.25-27.
• BARTOLO, M.E. and SCHWEISSING F.C. 2000. Onion storage trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7 p.28-29.
• BARTOLO, M.E. 2000. Onion Fertility Trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.25-27. p.30-31.
• BARTOLO, M.E. 1999. Onion nitrogen fertilizer trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.45-47.
• NISSEN, S. and BARTOLO, M.E. 2000. Onion weed control trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.43-56.
• BARTOLO, M.E. and SCHWEISSING, F.C. 2000. Effect of establishment method on the yield and quality of long green chile. Proceedings of the National Pepper Conference, Lafayette, LA. October 1-3. p 12.
• BARTOLO, M.E. 2000. Early cantaloupe trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.60-62.
• BARTOLO, M.E. 2000. Early Harvest PGR trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7.p.63-64.
• BARTOLO, M.E. 2000. Carrot hail damage trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ.Technical Report TR00-7. p.65-66.
• BARTOLO, M.E. 2000. Sweet corn variety trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.67-68.
• BARTOLO, M.E. 2000. Pepper variety trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.69-71.
• BARTOLO, M.E. 2000. Chile variety trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.72-73.
• BARTOLO, M.E. 2000. Hybrid chile establishment trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.74-75.
• BARTOLO, M.E. 2000. Bell pepper production trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.76-77.
• BARTOLO, M.E. 2000. Pepper disease control. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.78-79.
• BARTOLO, M.E. 2000. Spinach hail damage trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.80-81.
• BARTOLO, M.E. 2000. Tomato production trials. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.82-88.
• BARTOLO, M.E. 2000. Watermelon variety trial. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.89-90.
• BARTOLO, M.E. 2000. Early seedless watermelon. In 1999 Research Reports, Ark. Valley Res. Center, Colo. State Univ. Technical Report TR00-7. p.91-92.
• Nissen, S. J. and M. Bartolo. 2000. Pendimethalin and ethofumesate as DCPA replacements in dry bulb onions. Proceedings of Western Society of Weed Science 53:60

Progress 01/01/99 to 12/31/99

Outputs
Over 4,000 hectares of vegetables are grown annually in the Arkansas Valley of Colorado. One of the most profitable fresh market commodities sold thru road-side stands and other direct-markets is muskmelon (cantaloupe). Muskmelon from the Arkansas Valley command a high price due to their exceptional flavor and quality. Muskmelons are typically direct-seeded into bare ground in late April or early May and are furrow-irrigated. As a result, the marketing period is mainly limited to August and early September. During 1999, this program continued to investigate ways to extend the traditional marketing for muskmelons. The variety `Earligold' (Hollar Seeds) was grown using drip irrigation and various combinations of plastic mulches and row covers. The maturity of the muskmelon crop was greatly accelerated over the traditional marketing period by plasticulture techniques. Melons transplanted into clear plastic mulch and covered with clear perforated plastic tunnels matured the earliest. The first harvest occurred on June 30. Other combinations of mulches and row covers also enhanced the relative earliness of the crop. Marketable yields were highest (> 42,000 kg per hectare) in those treatments that were either seeded or transplanted into clear mulch and covered with plastic row covers. Based on these results, plasticulture techniques can help growers enhance their marketing period for muskmelon by three to four weeks. Using a typical early season price of $ 1.10 per kg, gross returns from one hectare of early muskmelon would exceed $20,000. Although the estimated cost of using plasticulture is substantial ($2500-$4000 per hectare), overall net returns would be enhanced relative to traditional production methods due to improved yields and higher early season prices.

Impacts
To date, 10 area growers on approximately 400 hectares have employed some component of plasticulture examined in this project. The gross economic benefit in terms of increased yield and higher early season prices is estimated to be $ 1 million.

Publications

• Bartolo, M.E. and Schweissing, F.C. 1999. Effect of planting method, mulch, and rowcover combinations on earliness, yield, and fruit size of `Arriba' watermelon. HortScience (Abstract) 34:472.
• Bartolo, M.E. and Schweissing, F.C. 1999. Yield and quality response of carrot (Daucus carota L.) To simulated storm. HortScience (Abstract) 34:479.
• Bartolo, M.E. and Schweissing, F.C. 1999. Alternative transplant production in Colorado. Proceedings of the National Onion Research Conference, Sacramento, CA. December 10-12. pp 271-275.
• Halvorson, A.D., Follett, R.F. and Bartolo, M.E. 1999. Onion growth and N uptake in southeastern Colorado. Proceedings of the National Onion Research Conference, Sacramento, CA. December 10-12. pp 322-329.
• Bartolo, M.E. and Schweissing F.C. 1999. Onion variety trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.39-41.
• Bartolo, M.E. and Schweissing F.C. 1999. Onion storage trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.42-43.
• Bartolo, M.E. 1999. Row cover-grown transplant and over-wintering trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.44.
• Bartolo, M.E. 1999. Onion nitrogen fertilizer trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.45-47.
• Nissen, S. and Bartolo, M.E. 1999. Onion weed control trials. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.67-70.
• Bartolo, M.E. 1999. Cantaloupe variety trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.71-72.
• Bartolo, M.E. 1999. Early Harvest PGR trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 73-74.
• Bartolo, M.E. 1999. Carrot hail damage trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.75-76.
• Bartolo, M.E. 1999. Sweet corn variety trials. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 77-79.
• Bartolo, M.E. 1999. Pepper production trials. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 80-84.
• Bartolo, M.E. 1999. Pepper fertility trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 85-86.
• Bartolo, M.E. 1999. Tomato production trials. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 87-90.
• Bartolo, M.E. 1999. Watermelon variety trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.91-92.
• Bartolo, M.E. 1999. Zinnia hail damage trial. In 1998 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.93-94.

Progress 01/01/98 to 12/31/98

Outputs
Over 4,000 hectares of vegetables are grown annually in the Arkansas Valley of Colorado. Onions are the most widely grown and one of the most intensively managed vegetable crop. With the exception of varieties, onions have been cultured in the same manner for decades using furrow irrigation and conventional pesticides. Excessive inputs of fertilizer, pesticides, and irrigation water may have negative environmental consequences. Nitrate-nitrogen moved readily out of the root zone when both conventional and slow-release fertilizers were applied to furrow-irrigated onions. Slow-release fertilizers (sulfur and polymer-coated urea) were somewhat less prone to leaching below the onion root zone(45 cm). Nonetheless, high concentrations of nitrate-nitrogen were detected in the center of the onion bed after harvest regardless of the type of fertilizer used. Various rates and types of soil-applied nitrogen fertilizers and a foliarly-applied phosphorus fertilizer did not have a significant(P< .05) impact on total onion yield or market class distribution. The lack of yield response may be due to the residual nitrate-nitrogen (33 ppm) present in the soil prior to planting. Overall, via N15 studies, the nitrogen use efficiency for onions was found to be very low (11.4%) and early season nitrogen applications were very ineffective and prone to leaching. In addition, early season fertilizer applications reduced onion germination and seedling vigor. Based on these results, soil testing prior to planting may help growers reduce or eliminate nitrogen fertilizer applications, saving them an estimated $300-$350 per hectare on fertilizer alone and reducing the potential for nitrate leaching. In addition, delaying fertilizer applications may improve stands and ultimately net economic returns.

Impacts
(N/A)

Publications

• Bartolo, M.E. 1998. Watermelon variety trial. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.91-92.
• Bartolo, M.E. 1998. Early watermelon trial. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.93-94.
• Bartolo, M.E. 1998. Yield response of zinnia to simulated storm damage. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 95.
• Bartolo, M.E. and Schweissing, F.C. 1998. Yield and quality response of muskmelon to simulated storm damage. HortScience 33:34-35.
• Bartolo, M.E. 1998. Onion variety trial. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.46-48.
• Bartolo, M.E. 1998. Onion storage trial. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.49-51.
• Bartolo, M.E. 1998. Alternative onion transplant production. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.52-55.
• Bartolo, M.E. 1998. Pam and seed treatment for onions. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.56-57.
• Nissen, S. and Bartolo, M. 1998. Crop safety of pre and post emergence hebicides in onions. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.67-69.
• Bartolo, M.E. 1998. Early cantaloupe production trial. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.70-72.
• Bartolo, M.E. 1998. Yield response of carrot to simulated storm damage. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 73.
• Bartolo, M.E. 1997. Cucurbit varieties. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 74-75.
• Bartolo, M.E. 1998. Early sweet corn varieties. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 76-78.
• Bartolo, M.E. 1998. Pepper production trials. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 79-83.
• Bartolo, M.E. 1998. Tomato production trials. In 1997 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 85-90.

Progress 01/01/97 to 12/31/97

Outputs
In the wake of public concern over food safety and pesticide use, growers are being faced with the possibility of producing crops without traditional methods. Colorado vegetable growers, in particular, have few alternative productions methods that will enable them to maintain their already slim margin of profit in the face of increasing competition for land and water resources. Over 4,000 hectares of vegetables are grown annually in the Arkansas Valley of Colorado. With the exception of changing varieties, most vegetable crops have been cultured in the same manner for decades using furrow irrigation and conventional pesticides. Nationwide, there has been a tremendous increase in the use of plasticulture for vegetable crops. The primary driving force behind the adoption of plasticulture practices has been water conservation via drip irrigation. Drip irrigation has made other plasticulture applications like mulching more practical. In the Arkansas Valley, the adoption of plasticulture techniques has been slow because irrigation water is currently inexpensive. Nonetheless, plasticulture may have a number of other attributes that would make its use economically and environmentally beneficial. Several plasticulture techniques have been adapted for the Arkansas Valley. Cantaloupe harvest has been advanced by 21 to 26 days and yield increased by up to 50% over conventional production methods by using a combination of hybrid varieties, row covers, plastic mulch and drip irrigation. Early cantaloupe production, via plasticulture, has the potential to net growers $14,000 to $16,000 per hectare based on current retail market prices and at the same time, reduce environmental impacts due to irrigation water run-off and pesticide applications.

Impacts
(N/A)

Publications

• BARTOLO, M.E. , SCHWEISSING, F.C., and VALLIANT, J.C. 1997. Nutrient management of onions: A Colorado perspective. Proceedings of the Western Nutrient Management Conference, Vol. 2:114-118. Salt Lake City, UT. March 6-7.
• BARTOLO, M.E. 1997. Onion storage trial. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.45-47. (unpub).
• BARTOLO, M.E. 1997. PAM and seed treatment for onions. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.48-49. (unpub).
• PERTIWI, S.R.R., POUUDRIER D., FRAMPTON, A., BARTOLO, M.E., SCHWARTZ, H.F., and BECHTEL. P.J. 1997. Effects of storage and shelf-life time and temperature on the quality of onions. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.50-54. (unpub).
• BARTOLO, M.E., CRANSHAW, W., and SCHWARTZ, H.F. 1997. Rocky Ford onion IPM experiment. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.61-62. (unpub).
• NISSEN, S. and BARTOLO, M. 1997. Onion weed control research In1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.67-70. (unpub).
• BARTOLO, M.E. 1997. Early cantaloupe production. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.73-75. (unpub).
• BARTOLO, M.E. 1997. Shipping cantaloupe production. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 76-77. (unpub).
• BARTOLO, M.E.,NISSEN, S., and TRANEL, J. 1997. Carrot production trials. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.82-84. (unpub).
• BARTOLO, M.E. 1997. Early sweet corn production. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 85-87. (unpub).
• BARTOLO, M.E. 1997. Pepper variety trial. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 88-92. (unpub).
• BARTOLO, M.E. 1997. Tomato variety trial. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p 93-94. (unpub).
• BARTOLO, M.E. 1997. Watermelon production. In 1996 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.97-98. (unpub).

Progress 01/01/96 to 12/30/96

Outputs
The effects of using soil-stabilizing polyacrylamide (PAM) on onion yield and soil erosion were evaluated. No significant yield or market class distribution changes occurred when PAM was added to irrigation water at a rate of 1.15 kg/ha. However, treating irrigation water with PAM reduced soil erosion by 51.9% compared to the untreated control. Several commercially available soil amendments were examined in a field trial. Ammonium polysulfide (Hickson Kerley), potassium thiosulfate (Hickson Kerley), and Sper Sal (FMC) did not alter onion yield and did not reduce soil salinity. Nitrate concentrations in onion leaves were also measured at different stages of plant development with a commercially available hand-held meter. Nitrate levels in the youngest fully expanded leaf were 900-1000, 400-600, and 200-300 ppm at pre-bulbing, bulbing, and bulb-sizing, respectively. Mid-season tissue testing continues to be examined as a diagnostic tool that can complement pre-season soil sampling.

Impacts
(N/A)

Publications

• BARTOLO, M.E. 1996. Onion nitrogen fertilizer trial-1995. In 1995 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p.63-65.
• BARTOLO, M.E. 1996. Developing an in-field diagnostic test for assessing onion nitrogen status. In 1995 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 66.
• BARTOLO, M.E. AND SCHWEISSING, F. C. 1996. Onion variety trial-1995. In 1995 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 59-62.
• BARTOLO, M.E. 1996. Soil amendments for onions. In 1995 Research Reports, Ark. Valley Res. Center, Colo. State Univ. p. 68.
• BARTOLO, M.E., SCHWEISSING, F. C., and VALLIANT, J.C. 1996. Irrigation and nitrogen fertility management for Colorado onions. Proc. Natl. Onion Res. Conf.,Madison, WI. p. 144-148.
• SUTHERLAND, P. L., et al. CropFlex-A valdose zone quality and farm sustainabilitydecision support tool for managing irrigation and fertilizer. Proc. Central Great Plains Irrigation Short Course, Burlington, CO.

Progress 01/01/95 to 12/30/95

Outputs
The effects of nitrogen fertilizer on onion yield and storage quality and residual soil nitrate were evaluated. No significant yield differences occurred when 112 to 336 kg/ha nitrogen was applied to two different onion cultivars. Storage quality as measured by percent shrinkage and sprouting was reduced when 224 or 336 kg/ha nitrogen was applied to onions. Residual soil nitrate-nitrogen measured after onion harvest was approximately four times higher in treatments fertilized with 336 kg/ha than in unfertilized control treatments. Nitrate concentrations in onion leaves were also measured at different stages of plant development with a commercially available hand-held meter. Nitrate levels in the youngest fully expanded leaf were 900-1000, 400-600, and 200-300 ppm at pre-bulbing, bulbing, and bulb-sizing, respectively. Mid-season tissue testing is a potential diagnostic tool that may complement pre-season soil sampling in a nitrogen management program for onion production.

Impacts
(N/A)

Publications

• BARTOLO, M.E. 1995. Onion nitrogen fertilizer trial-1994. In 1994 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.72-74. "unpub".
• BARTOLO, M.E. 1995. Onion fertility requirements. In 1994 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.75-76. "unpub".
• BARTOLO, M.E. AND SCHWEISSING, F.C. 1995. Onion variety trial-1994. In 1994 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.70-71. "unpub".
• SCHWARTZ H.F. AND BARTOLO, M.E. 1995. Colorado onion production and integrated pest management. Colo. State Univ. Bulletin 547A.

Progress 01/01/94 to 12/30/94

Outputs
The effects of nitrogen fertilizer on onion growth and onion storage quality were evaluated. No significant yield differences occurred when up to 300 lbs. per acre nitrogen was applied to three different onion cultivars. Initial storage results indicated that excessive nitrogen may reduce storage quality particularly in white and red-skinned onions. Long term storage results are still pending. Nitrogen fertilizer recommendations were established for Colorado onions. Specifically, nitrogen fertilizer applications are not necessary when pre-season soil nitrate levels are above 40 ppm. Nitrate concentrations in onion leaves were measured at different stages of plant development with a commercially available hand-held meter. An in-the-field diagnostic test is being developed that will use leaf nitrate concentrations to assess the nitrogen requirements of the onion crop.

Impacts
(N/A)

Publications

• BARTOLO, M.E. 1994. Onion alternative nitrogen fertilizer trial. In 1993 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.72-76. "unpub".
• BARTOLO, M.E. 1994. Onion irrigation study. In 1993 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.77-78. "unpub".
• BARTOLO, M.E. AND SCHWEISSING, F. C. 1994. Onion Variety Trial-1993. In 1993 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.62-70. "unpub".
• SCHWARTZ H.F., BARTOLO, M.E. AND SCHWEISSING, F. C. 1994. Onion responses to defoliation and soil-line infection by Botrytis. In National Onion Research Conference Proceedings, Ithaca NY.

Progress 01/01/93 to 12/30/93

Outputs
The effects of alternative nitrogen fertilizers and application methods on oniongrowth and nitrogen losses via leaching were evaluated. No significant yield differences occurred when either single or split applications of ammonium nitrate were applied. Similarly, slow-release fertilizers and foliar-applied nitrogen (whether in the form of nitrate, ammonium, or urea) did not induce a yield response. A significant amount of applied nitrogen is lost to denitrification or leaching with typical production practices. Nitrogen fertilizer applications are not necessary when pre-season soil nitrate levels are above 45 ppm. The effect of irrigation water quality and quantity on onion growth and development and nitrogen losses via leaching were also investigated. Based on weather-dependant crop growth models, three different levels of irrigation were applied to an onion crop after stand establishment. The levels included 25% more and 25% less than a standard irrigation volume. Yields were increased when higher volumes of irrigation water were applied. Higher irrigation levels resulted in increased leaching of nitrate-nitrogen and higher salt accumulation in the soil.

Impacts
(N/A)

Publications

• ELLS J.E., MCSAY, A.E., SOLTANPOUR, P.N., SCHWEISSING, F.C., BARTOLO, M.E., AND KRUSE, E.G. 1992. Onion irrigation and nitrogen leaching in the Arkansas Valley of Colorado 1990-1991. HortTech. 3:184-187.
• BARTOLO, M.E. 1993. Onion alternative nitrogen fertilizer trial. IN 1992 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.62-65. "unpub".
• BARTOLO, M.E. 1993. Onion irrigation study. IN 1992 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.66-67. "unpub".
• BARTOLO, M.E. AND SCHWEISSING, F.C. 1993. Onion Variety Trial-1992. IN 1992 Research Reports, Ark Valley Res. Center, Colo. State Univ. pp.53-61. "unpub".
• BARTOLO, M.E. AND SCHWEISSING, F.C. 1993. Amount of irrigation water applied to onions affects salinity build-up and nitrogen movement in the soil. IN National Onion Research Conference Proceedings, Ithaca NY.

Progress 01/01/92 to 12/30/92

Outputs
The effects of alternative nitrogen fertilizers and application methods on oniongrowth and nitrogen losses via leaching were evaluated. No significant yield differences occurred when either single or split applications of ammonium nitrate were applied. Similarly, slow-release fertilizers and foliar-applied nitrogen (whether in the form of nitrate, ammonium, or urea) did not induce a yield response. Chemical analyses of leaf, bulb, and soil samples are currently being conducted to determine plant uptake and losses due to leaching. The effect of irrigation water quality and quantity on onion growth and development and nitrogen losses via leaching were also investigated. Based on weather- dependant crop growth models, three different levels of irrigation were applied to an onion crop after stand establishment. The levels included 25% more and 25% less than a standard irrigation volume. No significant yield difference occurred between the irrigation levels. On the average, however, yields were increased when higher volumes of irrigation water were applied. Chemical analyses of onion leaves and bulbs are being conducted to determine how different irrigation levels affect nitrogen uptake. Soil samples are being analyzed for both nitrogen and salt content.

Impacts
(N/A)

Publications

• BARTOLO, M.E. 1992. Performance of alternative nitrogen fertilizers and application methods on onions. Industry Report. "unpub".
• BARTOLO, M.E. 1992. Yield response of onions to different forms of foliar- applied nitrogen. Industry Report. "unpub".
• BARTOLO, M.E. AND SCHWEISSING, F.C. 1992. Onion Variety Trial-1991. In 1991 Research Reports, Ark, Valley Res. Center, Colo. State Univ. pp.60-66. "unpub".
• ELLS J.E., MCSAY, A.E., SOLTANPOUR, P.N., SCHWEISSING, F.C., BARTOLO, M.E., AND KRUSE, E.G. 1992. Onion irrigation and nitrogen leaching: Arkansas Valley Research Center 1990-1991. In 1991 Research Reports, Ark, Valley Res. Center.