Source: OREGON STATE UNIVERSITY submitted to NRP
ASSESSING NITROGEN MINERALIZATION AND OTHER DIAGNOSTIC CRITERIA TO REFINE NITROGEN RATES FOR CROPS AND MINIMIZE LOSSES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0202872
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
NC-218
Project Start Date
Oct 1, 2001
Project End Date
Sep 30, 2006
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
OREGON STATE UNIVERSITY
(N/A)
CORVALLIS,OR 97331
Performing Department
MID-COLUMBIA AGRICULTURAL RES & EXTENSION CENTER
Non Technical Summary
Nitrogen use efficiency under surface broadcasting of dry N fertilizers to the soil surface has been reported to be low in tree fruit production systems in the Pacific Northwest. N fertigation through drip irrigation systems will be evaluated on pear and sweet cherry orchards and the guidelines about N fertigation and drip irrigation as an integrated production system will be developed.
Animal Health Component
40%
Research Effort Categories
Basic
10%
Applied
40%
Developmental
50%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1020110206125%
1020210206125%
1111112101025%
1111115101025%
Knowledge Area
102 - Soil, Plant, Water, Nutrient Relationships; 111 - Conservation and Efficient Use of Water;

Subject Of Investigation
1112 - Cherry; 0110 - Soil; 0210 - Water resources; 1115 - Pear;

Field Of Science
1010 - Nutrition and metabolism; 2061 - Pedology;
Goals / Objectives
1. Conduct fundamental work to enhance current understanding of the role of active C and N pools in cropping systems and to predict net N mineralization as influenced by C sequestration management and other management practices. 2. Develop a guidance document for agricultural professionals focusing on N best management practices and optimum rate determinations for the region.
Project Methods
Tree fruit production is highly dependent on N fertilizer to maintain suitable yields in the Pacific northwestern region. Currently, N fertilizer is broadcast applied to the soil surface as a dry material, and N use efficiency is far less than optimal with this traditional N management practice. Overall, this N management practice results in unnecessary N fertilizer consumption by orchards throughout the region, and increase the production costs on N fertilizer. In addition, low N use efficiency has significant negative impacts on tree fruit quality and storability, and on the environment as well. Therefore, it is essential to develop innovative best N management strategies and practices to increase N use efficiency for the Northwest horticultural crop production systems. Nitrogen fertigation has been reported to be an effective alternative to broadcast application of dry N fertilizer to the soil surface on some other crops in the United States. For example, N fertilizer rate was reduced by 50% using N fertigation relative to surface broadcast application of dry N fertilizer (Stiles, 1994). However, N fertigation has not yet been evaluated on pears and sweet cherries in the Northwestern region. There are no guidelines available about N management for N-fertigated pear in the Northwestern region. Similar to N fertilizer application, irrigation is another key management practice for pear and sweet cherry production, and has significant impacts on N uptake and nitrate leaching. Currently, impact and micro sprinkler systems are the main irrigation forms. Water use efficiency is below optimal with these irrigation systems. In addition, water is often over-irrigated on orchards to prevent yield loss from under watering due to the abundance and low cost of water in the region. Overall, low water use efficiency and over water application in the region cause unnecessary loss of water down to ground water. The increased water loss results in elevated leaching of nitrate from the N fertilizer applied and nitrogen in the soil down to underground water. Drip irrigation has been proven to have higher water use efficiency and low nitrate leaching than impact and micro sprinkler irrigation on some crops. For example, water consumption in potato production was reduced by as much as 50% using drip irrigation compared with micro sprinkler in Minnesota (Waddell et al., 1999). However, drip irrigation has not been evaluated on orchard trees in Oregon and the Northwest. No guidelines are available about water management for drip irrigated pears and sweet cherries. This project uses an integrated approach to conduct research. The project seeks to address nitrate contamination by using a brand new N management practice and technology (N fertigation) to reduce the contamination source (N fertilizers applied to the orchards). No similar evaluations have been conducted in the Pacific Northwest before. Replicated field plot experiments will be conducted to evaluate N fertigation. We will monitor tree growth, fruit yield, quality, and storability, revenue and cost, and N use efficiency and nitrate leaching.

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

Outputs
A field experiment of adult pears was conducted in a split split-plot design at Hood River, OR. Two N management and irrigation systems (split fertigation of N fertilizer through drip irrigation, single broadcast application of dry N fertilizer to the soil surface under micro sprinkler irrigation) were evaluated on pear cultivars of Bartlett and Golden Russet Bosc and rootstocks of OHxF97 and OHxF87 in 2005 and 2006. Another field trial was implemented on adult Anjou pear at Hood River, OR to evaluate N application rates (0, 45, 90, 135, 180, 225, 270, 315 kg N ha-1) and timings (spring, fall) on pear yield and quality in 2005 and 2006. The third field experiment was conducted at The Dalles, OR. Four ground management systems (straw mulch, white fabric cover, black fabric cover, and no cover) and two irrigation systems (single-line drip irrigation, micro sprinkler) were evaluated on sweet cherry in a split-plot design in 2005 and 2006. The following measurements were taken on an individual plot basis: soil moisture; soil nitrate, ammonium, and amino sugar N; leaf N concentration; tree vigor; fruit yield, size, firmness, color, and storability; cost and economic returns; and water and N use efficiencies. On the two trials at Hood River, the split N fertigation and drip irrigation system reduced N fertilizer use by 20% and irrigation water consumption by over 70% compared with our current system - single broadcast application of dry N fertilizer to the soil surface and micro sprinkler irrigation averaged over the four cultivar and rootstock combinations during the entire season in both years. Pear yield and quality were similar for the split N fertigation and drip irrigation system and our current N and water management system. Additionally, pear yield was similar with the different N application rates in both seasons; which suggests that the current N application rates of 90 to 110 kg N ha-1 used by growers could be reduced significantly. On the trial at The Dalles, single-line drip irrigation reduced irrigation water consumption by about 70% relative to micro sprinkler during the entire season from May to September. Black fabric, white fabric, and straw mulch reduced water use slightly compared with no cover. Cherry yield with single-line drip irrigation was similar to that under micro sprinkler. There was a strong trend of yield increase although statistically insignificant with straw mulch and fabric covers relative to no cover. Fruit sugar content, firmness, or size did not differ regardless of irrigation and ground cover system. The reduced water use with single-line drip irrigation suggests that nitrate leaching to underground water could be reduced by single-line drip irrigation. Overall, our first two-year results suggest that the split N fertigation and drip irrigation system is a profitable and environmentally sound management system for N and water in pear and cherry production in the Mid-Columbia region. The current N application rates used by growers could be reduced significantly. Single-line drip irrigation and ground covers maybe could increase N use efficiency by reducing nitrate leaching to underground water.

Impacts
Nitrogen and water use are both inefficient on orchards in the Mid-Columbia region; which has resulted in excessive N and water use, increased production costs, reduced fruit quality, and contaminated water. Although growers and state agencies have found these problems, there is no means available that growers can use to solve them. The objective of this project was to develop best N and water management systems for orchards. Two different N and water management systems (split fertigation of N fertilizer under drip irrigation, single broadcast application of dry N fertilizer to soil surface under micro sprinkler irrigation) were compared under different pear cultivars and rootstocks. Different N application rates and timings were evaluated on Anjou pears. Four ground cover systems and two irrigation systems were evaluated on sweet cherry. The split N fertigation and drip irrigation system seems to be an effective replacement to our current N and water management system. Nitrogen fertilizer and water use was reduced by 20% and 70%, respectively, using the split N fertigation and drip irrigation system compared with our current system. Fruit yield and quality were comparable under these two production systems. The profitability of each system has not been calculated; however, the researchers believe that the split N fertigation and drip irrigation system will be more profitable. Additionally, the current N application rates used by growers could be reduced significantly. Single-line irrigation saved over 70% of irrigation water; which could reduce orchard nitrate leaching.

Publications

  • Yin, X., C.F. Seavert, and J. Bai. 2007. Nitrogen and P management alternatives for pears. Proceedings of Western Nutrient Management Conference. Salt Lake City, UT. Mar. 8-9.
  • Yin, X., C.F. Seavert, and J. Bai. 2007. Split fertigation of N and P fertilizers on pears in Pacific Northwest. Proceedings of Fluid Fertilizer Foundation Forum. Phoenix, AZ. Feb. 18-20.


Progress 10/01/01 to 09/30/06

Outputs
A field experiment of adult pears was conducted in a split split-plot design at Hood River, OR. Two N management and irrigation systems (split fertigation of N fertilizer through drip irrigation, single broadcast application of dry N fertilizer to the soil surface under micro sprinkler irrigation) were evaluated on pear cultivars of Bartlett and Golden Russet Bosc and rootstocks of OHxF97 and OHxF87 in 2005 and 2006. Another field trial was implemented on adult Anjou pear at Hood River, OR to evaluate N application rates (0, 45, 90, 135, 180, 225, 270, 315 kg N ha-1) and timings (spring, fall) on pear yield and quality in 2005 and 2006. The third field experiment was conducted at The Dalles, OR. Four ground management systems (straw mulch, white fabric cover, black fabric cover, and no cover) and two irrigation systems (single-line drip irrigation, micro sprinkler) were evaluated on sweet cherry in a split-plot design in 2005 and 2006. The following measurements were taken on an individual plot basis: soil moisture; soil nitrate, ammonium, and amino sugar N; leaf N concentration; tree vigor; fruit yield, size, firmness, color, and storability; costs and economic returns; and water and N use efficiencies. On the two trials at Hood River, the split N fertigation and drip irrigation system reduced N fertilizer use by 20% and irrigation water consumption by over 70% compared with our current system - single broadcast application of dry N fertilizer to the soil surface and micro sprinkler irrigation averaged over the four cultivar and rootstock combinations during the entire season in both years. Pear yield and quality were similar for the split N fertigation and drip irrigation system and our current N and water management system. Additionally, pear yield was similar with the different N application rates in both seasons; which suggests that the current N application rates of 90 to 110 kg N ha-1 used by growers could be reduced significantly. On the trial at The Dalles, single-line drip irrigation reduced irrigation water consumption by about 70% relative to micro sprinkler during the entire season from May to September. Black fabric, white fabric, and straw mulch reduced water use slightly compared with no cover. Cherry yield with single-line drip irrigation was similar to that under micro sprinkler. There was a strong trend of yield increase although statistically insignificant with straw mulch and fabric covers relative to no cover. Fruit sugar content, firmness, or size did not differ regardless of irrigation and ground cover system. The reduced water use with single-line drip irrigation suggests that nitrate leaching to underground water could be reduced by single-line drip irrigation. Overall, our first two-year results suggest that the split N fertigation and drip irrigation system is a profitable and environmentally sound management system for N and water in pear and cherry production in the Mid-Columbia region. The current N application rates used by growers could be reduced significantly. Single-line drip irrigation and ground covers maybe could increase N use efficiency by reducing nitrate leaching to underground water.

Impacts
Nitrogen and water use are inefficient on orchards in the Mid-Columbia region, OR; which has resulted in excessive N and water use, increased production costs, reduced fruit quality, and contaminated water. This project has developed some best N and water management systems for orchards. Our results show the split N fertigation and drip irrigation system is a viable replacement to the current N and water management system. Nitrogen fertilizer and water use were reduced by 20% and 70%, respectively, fruit yield and quality were comparable, and grower profitability was increased by $50/acre using the split N fertigation and drip irrigation system relative to our current system. Additionally, the current N application rates used by growers could be reduced significantly and single-line irrigation saved over 70% of irrigation water with no detrimental effect on fruit production. The impacts of this project on economics, environment, and society are significant. For instance, 80% of the 600 targeted growers have been educated through this project. More and more growers begin to use these best N and water management systems into production. We believe our results will be widely used on the 20,000 orchard acres in the Mid-Columbia region, and hundreds of thousands of orchard acres in Oregon and the Pacific Northwest. These best N and water management systems will reduce nitrate and herbicide leaching to the underground water by over 30%, and restore streamflow in streams and rivers and thus improve fish production and the conditions for tourism and recreation in the region.

Publications

  • Yin, X., C.F. Seavert, and J. Bai. 2007. Nitrogen and P management alternatives for pears. Proceedings of Western Nutrient Management Conference. Salt Lake City, UT. Mar. 8-9.
  • Yin, X., C.F. Seavert, and J. Bai. 2007. Split fertigation of N and P fertilizers on pears in Pacific Northwest. Proceedings of Fluid Fertilizer Foundation Forum. Phoenix, AZ. Feb. 18-20.


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

Outputs
A field experiment of adult pears was conducted in a split split-plot experimental design at Hood River, OR. Two N management and irrigation systems (fertigation of N fertilizer through drip irrigation, broadcasting application of dry N fertilizer to the soil surface under micro-sprinkler irrigation) were evaluated on pear cultivars of Bartlett and Golden Russet Bosc and rootstocks of OH-F97 and OH-F87. Another field trial was initiated on adult Anjou pear at Hood River, OR to evaluate N application rates (0, 45, 90, 135, 180, 225, 270, 315 kg N/ha) and timings (spring, fall) on pear yield and quality. The third field experiment was conducted at The Dalles, OR. Two irrigation systems (drip irrigation, micro sprinkler) and four ground management systems (straw mulch, white fabric cover, black fabric cover, and no cover) were evaluated on sweet cherry in a split-plot design. Irrigation was scheduled based on soil moisture for each trial. The following measurements were taken on an individual plot basis: soil moisture; soil nitrate, ammonium, and amino sugar N; leaf N concentration; tree vigor; fruit yield, size, firmness, color, and storability; cost and economic returns; and water and N use efficiencies. On the two trials at Hood River, the integrated N fertigation and drip irrigation system reduced N fertilizer use by 20% and irrigation water consumption by 73% compared with our current system -- broadcasting application of dry N fertilizer to the soil surface plus micro-sprinkler irrigation averaged over the four cultivar and rootstock combinations during the entire season from May to September. Pear yield and quality were similar for the integrated N fertigation and drip irrigation system and our current N and water management system. Additionally, pear yield was similar for the different N application rates; which suggests that the current N application rates of 90 to 110 kg N/ha used by growers could be reduced significantly. On the trial at The Dalles, drip irrigation reduced irrigation water consumption by 74% relative to micro sprinkler during the entire season from May to September. Compared with no cover, black fabric lowered water use by 8%, and other covers reduced water use by 1 to 3%. Cherry yield with drip irrigation was similar to that under micro sprinkler. There was a strong trend of yield increase although statistically insignificant with straw mulch and fabric covers relative to no cover. Fruit sugar content, firmness, or size did not differ regardless of irrigation and ground cover. The reduced water use with drip irrigation suggests that nitrate leaching to underground water could be reduced by drip irrigation. Overall, our first-year results suggest that the integrated N fertigation and drip irrigation system is a profitable and environmentally sound management system for N and water in pear and cherry production in the Mid-Columbia region. The current N application rates used by growers could be reduced significantly. Drip irrigation and ground covers maybe could increase N use efficiency by reducing nitrate leaching to underground water.

Impacts
Nitrogen and water use are both inefficient on orchards in the Mid-Columbia region; which has resulted in excessive N and water consumption, increased production costs, reduced fruit quality, and contaminated water. Although growers and state agencies have found these problems, there is no means available that growers can use to solve them. The objective of this project was to develop best N and water management systems for orchards. Two different N and water management systems (fertigation of N fertilizer through drip irrigation, broadcasting application of dry N fertilizer to soil surface under micro-sprinkler irrigation) were compared under different pear cultivars and rootstocks. Different N application rates and timings were evaluated on Anjou pears. Two irrigation systems and four ground cover systems were evaluated on sweet cherry. The integrated N fertigation and drip irrigation system seems to be an effective replacement to our current N and water management system. Nitrogen fertilizer and water consumption was reduced by 20% and 73%, respectively, using the integrated N fertigation and drip irrigation system compared with our current system. Fruit yield and quality were comparable under these two production systems. The profitability of each system has not been calculated; however, the researchers believe that the N fertigation and drip irrigation system will be more profitable. Additionally, the current N application rates used by growers could be reduced significantly. Drip irrigation saved 74% of water; which could reduce orchard nitrate leaching.

Publications

  • No publications reported this period