Progress 09/15/04 to 06/15/06
Outputs
Progress Report 1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? The effectiveness of most production practices is evaluated at harvest by examining final yield. However, an understanding of the mechanisms that drive these final yield numbers is vital in determining the efficacy of production strategies and technologies. Most causal mechanisms are physiologically based; therefore, an examination of the physiological responses to the production environment can help determine how production practices succeed or fail. Research will be conducted to investigate and improve the understanding of the physiological responses to environment, climate, and production practices that ultimately determine peanut yield and quality. Major emphasis will be directed towards examining the effects of irrigation type and amount on peanut physiological water use and
evaluating water-use efficiency under varying water environments. Emphasis will also be placed on plant and kernel susceptibility to aflatoxin contamination and tomato spotted wilt virus, and their effects on water use and other plant and kernel physical characteristics. How serious is the problem? The picture of water availability across most of the U.S. peanut producing areas is bleak and becoming worse every year. Drought and decreased water availability through urban use has affected almost every peanut producing region in the U.S. over the last decade. In certain regions, the problem is reaching critical levels. For example in 2002, 54 counties in the North Carolina agriculture belt were declared disaster areas due to high crop losses during a severe growing season drought (Governors office, U.S. Dept. of Agric.). Because of this reality, high water-use efficiency in peanut production can spell the difference between high yields or a failed crop when water is limited. Because
of the high economic and aflatoxin risks associated with dryland peanut production, growers have become increasingly dependent on irrigation to make economically viable yields. Irrigated peanut acreage now comprises over 50% of all peanut production in the U.S. and can increase yields by up to 19% over dryland production. Yet, due to the often precarious balance between these increased yields and the high cost of irrigation equipment, maintenance, and fuel, it becomes necessary for a grower to maximize the efficiency of water application as much as possible. One area that has the possibility of tipping the scales in favor of growers is maximizing peanut water-use efficiency while maintaining optimum production. The economic losses associated with two major diseases of peanut, tomato spotted wilt virus and aflatoxin, can also be devastating. Tomato spotted wilt Tospovirus (TSWV) costs an estimated $100 million annually to southeastern agricultural commodities including the peanut
industry, and in 2002 totaled $40 million in losses in Georgia alone through reduction in yields. Economic losses due to aflatoxin can be significant if drought is a factor during the latter part of the growing season. In these years, significant aflatoxin contamination can occur and results in a large diversion of peanuts from the edible supply, and this action threatens the economic viability of the entire U.S. peanut industry, including growers, shellers, manufacturers, and allied businesses. Why does it matter? Greater efficiency in production continues to be the major goal for US producers. With increasing competition from world markets, the survival of US producers depends on their ability to use production inputs efficiently while maintaining superior crop quality. Quality parameters such as aflatoxin (toxins produced by fungi inhabiting peanuts), foreign materials, and flavor continue to be identified by all segments of the US peanut industry as major problems with severe
economic consequences each year. Technology fostering lower, more efficient production strategies while maintaining high quality peanuts entering the US and world markets would increase farm profitability and industry sustainability. This research will provide a basic knowledge about the physiological mechanisms behind efficient peanut production and an understanding of how these mechanisms can be monitored and eventually manipulated to improve production efficiency. For example, evaluating how peanuts use water over the entire growing season can aid in identifying varieties that are better at withstanding drought conditions without sacrificing yield, are less prone to aflatoxin under dry environmental conditions, and aid in determining more efficient irrigation regimes. To whom is the work relevant/what is the potential impact of the work? This research has relevance and can provide potential impact to all components of the peanut industry. The fundamental research into the
processes that underlie greater crop productivity and efficiency especially in the use of water resources has great impact on peanut growers. Information regarding water movement both through soils and crops is essential to developing improved practices to manage agricultural water resources by pinpointing crop water needs. This research also provides recommendations to growers for balancing soil resources and environmental quality that can provide more efficient use of agricultural water resources by quantifying soil infiltration, pesticide runoff, and plant available water in agricultural systems. Manufacturers can benefit from the information about how variability in water use can then translate into better product quality and safety from kernel flavor to aflatoxin resistance. Benefits can also be gained by an understanding of the causal physiological mechanisms behind disease progression and provide the ability to pinpoint the most effective time periods for disease management.
2. List by year the currently approved milestones (indicators of research progress) Identify physiological drought responses to quantify water-use efficiency and other physiological characteristics that influence peanut yield and quality (aflatoxin contamination, flavor, maturity) and how these traits may differ among resistant and susceptible cultivars. Certain physiological traits will be early indicators of water stress before visual wilting or other detrimental and long lasting drought effects on overall growth and yield occur. Year 1: plot establishment, data collection, and sample analysis was be completed on hypothesis 1 experiment, 1 examining tillage X irrigation amount on drought response Year 2: plot establishment, data collection, and sample analysis will be completed on hypothesis 1 experiment 1 examining tillage X irrigation amount on drought response; Conduct pilot study evaluating traits for irrigation scheduling Year 3: plot establishment, data collection, and sample
analysis will be completed on hypothesis 1 experiment 1 examining tillage X irrigation amount on drought response; Conduct pilot study evaluating traits for irrigation scheduling Year 4: Analysis of field data and reporting of results for tillage X irrigation amount experiment Hypothesis 2: The ability to respond quickly to developing moisture stress via physiological mechanisms will impart drought resistance advantages to genotypes and correlate with aflatoxin resistance in developing genotypes. Year 1: Analyze data from hypothesis 1 field studies in order to identify traits that are early indicators of drought stress Year 2: Utilizing early drought signals, conduct year 1 rainout shelter study examining differential drought response and correlation with aflatoxin in peanut germplasm Year 3: Year 2 data collection and analysis of rainout shelter study examining differential drought response and correlation with aflatoxin in peanut germplasm Year 4: Analyze data and report results
from rainout shelter study and identify difference in drought response and development of aflatoxin among peanut germplasm Objective 2: Characterize the physiological processes and genetic expression changes that impart a level of disease tolerance to Tomato spotted wilt virus in peanuts. Hypothesis 1: Physiological mechanisms mediate the ability of peanut varieties to either resist or tolerate Tomato spotted wilt virus (TSWV) infection. In addition, the success of some insecticide treatments is not entirely due to the thrips vector control but is a physiological response to the applied insecticide and is correlated with certain gene expression profiles. Year 1: Year 1 of data collection and analysis of physiological and genetic responses in the field study examining TSWV resistance among insecticide treatments and peanut varieties. Year 2: Year 2 of data collection and analysis of physiological and genetic responses in the field study examining TSWV resistance among insecticide
treatments and peanut varieties. Year 3: Data analysis of physiological and genetic responses in the field study examining TSWV resistance among insecticide treatments and peanut varieties. Hypothesis 2: The timing of infection, whether it is early or late in the season, will determine the severity of infection. Further, peanut genotypes will vary in their abilities to withstand either early or late infection or both through physiologically mediated resistance mechanisms. Year 3: Year 1 of data collection and analysis of greenhouse study utilizing mechanical inoculation of TSWV and examining differences among peanut germplasm in development and tolerance of the virus. Year 4: Year 2 of data collection and analysis of greenhouse study utilizing mechanical inoculation of TSWV and examining differences among peanut germplasm in development and tolerance of the virus. Year 5: Analyze and report results of greenhouse study utilizing mechanical inoculation of TSWV and examining differences
among peanut germplasm in development and tolerance of the virus. 4a List the single most significant research accomplishment during FY 2006. Research examining peanut phenological development and physiological response to tillage and irrigation was completed and data analyzed. Data available at this time included detailed measurements of root development and architecture, reproductive development as affected by tillage treatment, and direct measurements of water use in peanuts in conservation tillage. No research of this kind had been conducted in peanut previously and many grower groups expressed interest in these results; five invitations were received and results reported at grower seminars. 4b List other significant research accomplishment(s), if any. The first year of a project examining reduced irrigation application coinciding with peanut development in the west Texas production area was completed. This research has proven to be valuable in the development of possible
alternative irrigation strategies for this region due to the continued lowering of local aquifer levels and decreasing water availability to agricultural users. The project has been listed as one of the top research priorities to the manufacturing industry and has been supported by funding through the Peanut Foundation and the ARS Ogallala Aquifer initiative. 5. Describe the major accomplishments to date and their predicted or actual impact. Strategies and techniques for determining peanut physiological responses to the environment, and specifically to water availability, have been designed and successfully implemented. Techniques capturing water use by peanuts on many scales have been implemented including: sap flow gauges that determine water use on hourly increments and can be directly correlated to precipitation and irrigation application; biomass accumulation indices during several time periods during the growing season to follow response as influenced by plant development; the
use of deuterium (water with heavy hydrogen) for labeling and following the path of water through soil and peanut plants after simulated irrigation or precipitation events; and the use of carbon isotopes for determining water-use efficiency across an entire growing season under differing environments and across peanut genotypes. Successful implementation of these techniques has wide application and impact across many topics including: determining the best irrigation scheduling and strategies to minimize water-use efficiency in peanut; aid breeding efforts aimed at developing more water-use efficient varieties; and determining the effects of plant architecture (canopy and root) on pesticide, nutrient, and water movement and fate. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability
of the technology products? Information about ongoing irrigation research and improvements to irrigation scheduling and responses to TSWV were presented to university faculty, extension representatives, growers, industry representatives and congressional personnel throughout FY 2006 through invited seminars and scientific meetings. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Freeman, E.S. Biotech: Cutting-edge scientific research fins niche at ASU. Albany State University Research Review, Spring 2006. Rowland, D.L. 2005 Peanut Crop: A Different Look. Peanut Patriot, Winter 2006. Rowland, D., Faircloth, F. and Sullivan, D. When is the right time to dig? Southeastern Peanut Farmer, July/August 2006.
Impacts
(N/A)
Publications
- Rowland, D., Dorner, J.W., Sorensen, R.B., Beasley, J., Todd, J. The progression of tomato spotted wilt virus through peanut tissue types and the resultant physiological effects as related to severity of viral infection. American Peanut Research and Education Society Abstracts. www. apres.okstate.edu.
|
Progress 10/01/04 to 09/30/05
Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? The effectiveness of most production practices is evaluated at harvest by examining final yield. However, an understanding of the mechanisms that drive these final yield numbers is vital in determining the efficacy of production strategies and technologies. Most causal mechanisms are physiologically based; therefore, an examination of the physiological responses to the production environment can help determine how production practices succeed or fail. Research will be conducted to investigate and improve the understanding of the physiological responses to environment, climate, and production practices that ultimately determine peanut yield and quality. Major emphasis will be directed towards examining the effects of irrigation type and amount on peanut physiological water use and evaluating
water-use efficiency under varying water environments. Emphasis will also be placed on plant and kernel susceptibility to aflatoxin contamination and tomato spotted wilt virus, and their effects on water use and other plant and kernel physical characteristics. The picture of water availability across most of the U.S. peanut producing areas is bleak and becoming worse every year. Drought and decreased water availability through urban use has affected almost every peanut producing region in the U.S. over the last decade. In certain regions, the problem is reaching critical levels. For example in 2002, 54 counties in the North Carolina agriculture belt were declared disaster areas due to high crop losses during a severe growing season drought (Governors office, U.S. Dept. of Agric.). Because of this reality, high water-use efficiency in peanut production can spell the difference between high yields or a failed crop when water is limited. Because of the high economic and aflatoxin
risks associated with dryland peanut production, growers have become increasingly dependent on irrigation to make economically viable yields. Irrigated peanut acreage now comprises over 50% of all peanut production in the U.S. and can increase yields by up to 19% over dryland production. Yet, due to the often precarious balance between these increased yields and the high cost of irrigation equipment, maintenance, and fuel, it becomes necessary for a grower to maximize the efficiency of water application as much as possible. One area that has the possibility of tipping the scales in favor of growers is maximizing peanut water-use efficiency while maintaining optimum production. The economic losses associated with two major diseases of peanut, tomato spotted wilt virus and aflatoxin, can also be devastating. Tomato spotted wilt Tospovirus (TSWV) costs an estimated $100 million annually to southeastern agricultural commodities including the peanut industry, and in 2002 totaled $40
million in losses in Georgia alone through reduction in yields. Economic losses due to aflatoxin can be significant if drought is a factor during the latter part of the growing season. In these years, significant aflatoxin contamination can occur and results in a large diversion of peanuts from the edible supply, and this action threatens the economic viability of the entire U.S. peanut industry, including growers, shellers, manufacturers, and allied businesses. Greater efficiency in production continues to be the major goal for US producers. With increasing competition from world markets, the survival of US producers depends on their ability to use production inputs efficiently while maintaining superior crop quality. Quality parameters such as aflatoxin (toxins produced by fungi inhabiting peanuts), foreign materials, and flavor continue to be identified by all segments of the US peanut industry as major problems with severe economic consequences each year. Technology fostering
lower, more efficient production strategies while maintaining high quality peanuts entering the US and world markets would increase farm profitability and industry sustainability. This research will provide a basic knowledge about the physiological mechanisms behind efficient peanut production and an understanding of how these mechanisms can be monitored and eventually manipulated to improve production efficiency. For example, evaluating how peanuts use water over the entire growing season can aid in identifying varieties that are better at withstanding drought conditions without sacrificing yield, are less prone to aflatoxin under dry environmental conditions, and aid in determining more efficient irrigation regimes. This research has relevance and can provide potential impact to all components of the peanut industry. The fundamental research into the processes that underlie greater crop productivity and efficiency especially in the use of water resources has great impact on
peanut growers. Information regarding water movement both through soils and crops is essential to developing improved practices to manage agricultural water resources by pinpointing crop water needs. This research also provides recommendations to growers for balancing soil resources and environmental quality that can provide more efficient use of agricultural water resources by quantifying soil infiltration, pesticide runoff, and plant available water in agricultural systems. Manufacturers can benefit from the information about how variability in water use can then translate into better product quality and safety from kernel flavor to aflatoxin resistance. Benefits can also be gained by an understanding of the causal physiological mechanisms behind disease progression and provide the ability to pinpoint the most effective time periods for disease management. 2. List the milestones (indicators of progress) from your Project Plan. This project has not currently gone through the OSQR
review process. Therefore, no official milestones have been established. However, the overall objective of this project has been to determine the effects of diverse environmental conditions on the physiological characteristics of peanut and to develop a better understanding of how these physiological responses affect the overall production and quality of peanuts. Within this major objective two areas of emphasis have been established: 1) the major emphasis has been directed toward examining the effects of irrigation methods and modification of peanut physiological characteristics to improve crop quality and water-use efficiencies; and 2) emphasis has also been placed on plant and kernel susceptibility to aflatoxin contamination and tomato spotted wilt virus, and their effects on water use and other plant and kernel physical characteristics. 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially
met, or not met. If not met, why. 1. Examination of the effects of irrigation methods and modification of peanut physiological characteristics to improve crop quality and water- use effiencies. Milestone Substantially Met 2. Determining plant and kernel susceptibility to aflatoxin contamination and Tomato spotted wilt virus and their effects on water ue and other plant and kernel physical characteristics. Milestone Substantially Met 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? 1. Examination of the effects of irrigation methods and modification of peanut physiological characteristics to improve crop quality and water- use efficiencies. 2006: Experiments will be modified at the experimental farm in Dawson, GA. Crop water-use curves obtained from sap flow measurements in 2003, 2004, and 2005 for both peanut and cotton will be incorporated
into irrigation scheduling programs and tested at the later irrigation plots in Dawson. This research could potentially improve Irrigator Pro, the decision support system developed at the lab for irrigation scheduling of peanuts. Experiments will also be continued investigating peanut development, biomass accumulation, and water-use efficiency under three different irrigation scheduling methods in Camilla, GA. 2007: Experiments will be continued investigating the physiological effects of different tillage systems and irrigation scheduling methods on peanut water-use and soil water retention at experimental farms in Dawson, GA. 2008: Experiments will be continued investigating the physiological effects of different tillage systems and irrigation scheduling methods on peanut water-use and soil water retention at experimental farms in Dawson and Tifton, GA. 2. Determining plant and kernel susceptibility to aflatoxin contamination and tomato spotted wilt virus and their effects on water
use and other plant and kernel physical characteristics. 2006: Experiments will be continued for a third year relating aflatoxin (toxins produced by fungi inhabiting peanuts) production to the physiological drought response of peanuts. With the construction of greenhouse facilities in spring 2005, the potential for examining very small-scale differences among aflatoxin resistant and susceptible lines will be possible. These experiments would include further water labeling in order to follow the direct path of water entering the peanut hull and how this mechanism may contribute to aflatoxin resistance. Experiments will also be continued in order to quantify the development of Tomato spotted wilt virus (a major disease of peanuts) during the growing season and its percent reduction in physiological performance. The collaboration with the University of Florida will be continued so that genetic responses can be correlated with physiological mechanisms of resistance. 2007: Direction
to be determined with the second year results of the above experiments. 2008: Direction to be determined with the second year results of the above experiments. 4a What was the single most significant accomplishment this past year? Differences in peanut water-use under overhead and drip irrigation The effects of irrigation application method have been quantified as related to peanut water-use, canopy and root development, stress response, seasonal water-use efficiency, and yield. The comparison of a relatively inefficient irrigation method (overhead application) with one that has been purported to be more efficient (subsurface drip irrigation) was important because the actual plant water-use differences had not been previously measured in the two systems and the actual benefits of drip irrigation had not been quantified. During FY 2005, the third year of research was completed in which plant stem flow, soil moisture, crop development, and plant stressors were measured throughout the
growing season and compared between overhead and drip irrigation treatments. This research has provided information to growers about the actual benefits of these two irrigation options and will serve as a foundation with which to improve irrigation scheduling methods in both irrigation systems. 4b List other significant accomplishments, if any. Physiological and genetic responses to Tomato Spotted Wilt Virus Physiological and correlated genetic responses were measured throughout the growing season under heavy Tomato spotted wilt virus (TSWV) pressure. This research was important because it added information about the physiological and genetic responses to TSWV under insecticidal treatments when previous research had shown that any benefits to this treatment were not tied to the control of the insect vector of the disease. In collaboration with the University of Florida, the physiological gas exchange and drought responses of TSWV infected plants were correlated with instantaneous
gene expression products throughout the growing season. By identifying genetic responses associated with beneficial physiological traits, production methods that increase the resistance of peanut to TSWV can be aided both through breeding programs and improvements in the management of insecticide treatments for TSWV. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Strategies and techniques for determining peanut physiological responses to the environment, and specifically to water availability, have been designed and successfully implemented. Techniques capturing water use by peanuts on many scales have been implemented including: sap flow gauges that determine water use on hourly increments and can be directly correlated to precipitation and irrigation application; biomass accumulation indices during several time periods during the growing season to follow response as influenced by plant development; the use of
deuterium (water with heavy hydrogen) for labeling and following the path of water through soil and peanut plants after simulated irrigation or precipitation events; and the use of carbon isotopes for determining water-use efficiency across an entire growing season under differing environments and across peanut genotypes. Successful implementation of these techniques has wide application and impact across many topics including: determining the best irrigation scheduling and strategies to minimize water-use efficiency in peanut; aid breeding efforts aimed at developing more water-use efficient varieties; and determining the effects of plant architecture (canopy and root) on pesticide, nutrient, and water movement and fate. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the
technology products? Information about ongoing irrigation research and improvements to irrigation scheduling were presented to university faculty, extension representatives, growers, and congressional personnel at the Shellman Multi-Irrigation Research Facility field day. Information about conservation tillage and irrigation methods was presented at the Hooks Hanner Environmental Resource Center Grower Workshop including growers, university personnel, and state policy makers. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). National Peanut Day focuses on research at Capitol Hill. Southeastern Peanut Farmer, Vol. 43, Number 3, April 2005. Carter, J. Experimental irrigation strategy demonstrates promise for successful peanut crop. Southeastern Peanut Farmer, Vol. 43, Number 4, May/June 2005. Southern Peanut Growers Conference. Southeastern Peanut
Farmer, Vol. 43, Number 5, July/August 2005.
Impacts
(N/A)
Publications
- Rowland, D., Dorner, J.W., Sorensen, R.B., Beasley, J., Todd, J. The progression of tomato spotted wilt virus through peanut tissue types and the resultant physiological effects as related to severity of viral infection. American Peanut Research and Education Society Abstracts. www. apres.okstate.edu.
|