Progress 12/15/04 to 12/14/08
Outputs
OUTPUTS: Three students completed M.S. degrees and theses. We completed four years of a rotational study designed to determine if growing mustards in rotation with winter wheat and spring wheat produces a more sustainable rotation than the commonly used dryland winter wheat/spring wheat/pea rotation. We have completed data collection for variables including yields, weed densities, extractable and total nitrogen concentrations, earthworm populations, surface residues, carbon concentrations, microbial biomass, and soil bulk densities. Data on economic viability and environmental benefits of the different rotations were also generated. Additional tools were used to determine differences in soil quality attributes. In addition to completing the outlined analyses and assessments, we added a member to our team to model energy inputs and outputs, thus producing a life cycle analysis. We have also conducted research on the use of mustard seed meals as bioherbicides and N fertilizers in small-acreage, high-value cropping systems. Data concerning Brassica juncea, Brassica napus, and Sinapis alba seed meal impacts on strawberry establishment, vigor, yield, foliar N, and soil inorganic N were obtained in a 2-year field study. Data from a field study initiated to investigate the influence of these seed meals on carrot (Dacus carota L. var. sativus) growth and N mineralization have been summarized and a manuscript accepted for publication in a peer-refereed journal. Tracking of N mineralization from seed meal was performed in the laboratory using isotope labeling to show the rate of inorganic N release. Allelochemicals produced in seed meal-amended soil were measured and the depth of leaching determined in field soils. The work was published in a peer-refereed journal. The potential market for mustard meal as a biopesticide was evaluated. This evaluation focused on the residual cost of mustard meal needed to make the oil co-product competitive with soybean oil as a biodiesel feedstock. This cost was then compared to existing similar biopesticides to determine market feasibility. We have disseminated information about our project through on-farm field days (including: University of Idaho Parker Farm Field Days; University of Idaho Weed Science Field Days; and University of Idaho Soil Stewards Organic Farm Field Days), and attendance to and presentation at professional society and local grower group meetings (Soil Science Society of America, Western Society of Weed Science, International Weed Science Congress, FarWest Agribusiness Association, Idaho Canola Rapeseed Commission, Idaho Oilseed Conference and other local grower group meetings). We have counseled other researchers on the guidelines for use and potential hazards of using mustard seed meals as bioherbicides. We have a pending utility patent application entitled "Brassicaceae Plant Materials and Method for their use as Biopesticides". Contacts with potential business partners were established to commercialize the product. PARTICIPANTS: Matthew Morra analyzed plant-derived allelochemicals and guided development of meal biopesticides. Donald Thill was essential in designing, conducting, and analyzing field studies related to weed control in the rotational and organic farming plots. Jodi Johnson-Maynard conducted nitrogen mineralization studies and phytotoxicity experiments with strawberries and carrots. Larry Makus collected and analyzed economic data related to the rotations and meal utilization. Joseph McCaffrey provided technical expertise on insect control. Dev Shrestha collected data to calculate an overall energy balance for biodiesel production.Graduate students Andre Snyder and Lydia Clayton participated in meal experiments to develop biopesticides and quantify nitrogen dynamics in soil. Karl Umiker provided field and laboratory support for the rotational studies. TARGET AUDIENCES: Our target audiences included conventional farmers and small-scale organic farmers, crop advisors, and other researchers. We interacted quite often with organic growers, the target user group for our biopesticides. We also interacted with agricultural products companies in an attempt to secure funding that will facilitate commercialization efforts of our biopesticides. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Within the rotational plots we showed after one full crop rotation with mustards that there was no change in total soil C or total N content and thus, more time will be necessary before any potential benefits to total C or N are evident. Although soil bulk density did not differ among rotations, trends indicate that it is increasing under direct-seed management as compared to conventional tillage. Direct-seed management has the benefit of decreasing soil erosion, but continuous practice could eventually restrict root growth. After the effects of one complete rotation, earthworm and earthworm cocoon densities were not different among the rotations, however when earthworms and cocoons were summed together, rotations including yellow mustard (Sinapis alba) contained a greater density of individuals than did rotations including pea (Pisum sativum) or oriental mustard (Brassica juncea). There thus appear to be benefits to earthworms when growing yellow mustard. Plant-available nitrogen, as either ammonium or nitrate, was analyzed by crop sequence to identify differences directly following pea, yellow mustard, or oriental mustard crops. Ammonium concentrations after pea, yellow mustard, or oriental mustard were unaffected by crop type, however nitrate concentrations were higher after pea crops than after yellow mustard or oriental mustard. Data suggest that winter wheat following pea crops may require less fertilizer than those following yellow or oriental mustards. Within the small-acreage, high-value crops we determined that seasonal apparent net nitrogen mineralized expressed as a percentage of the total N applied in the seed meals was not affected by the type of mustard and ranged from 30 to 81% across both years. Brassicaceae seed meals can be used to increase soil inorganic N and carrot yields, but crop phytotoxicity is possible depending on the meal. Some seed meals produce degradation products that inhibit microbial N uptake in the short term, but longer-term N availability is not compromised. The most important of these degradation products acts as a bioherbicide that has value in high-value fruit and vegetable production. There is commercial value to producing a seed meal bioherbicide from which a wide variety of crops may benefit. We have met with EPA personnel and they have agreed that S. alba meal constitutes a new active ingredient and that it falls within regulatory purview of the Biopesticides Division. We have determined in field studies that the active ingredient has limited potential for off-site environmental impacts. With our work in strawberries and carrots, we have gained new knowledge on the potential challenges and uses of mustard seed meals as bioherbicides in small-acreage, high-value cropping systems. This new knowledge includes information about environmental and climatic conditions that affect efficacy of mustard seed meals as bioherbicides, sensitivity of various species to mustard seed meals, seed meal rates required to gain desired efficacy, and formulation of active ingredients to improve efficacy. This information is critical to developing a label and commercializing a product.
Publications
- Clayton, L.A. 2009. Brassicaceae seed meals as bioherbicides: Influence on plant growth and weed control in an organic production system. M.S. Thesis, University of Idaho, Moscow, Idaho (in press).
- Clayton, L.A., D. C. Thill, W. J. Price, and V. Borek. 2008. Yellow mustard seed meals and seed meal extracts as bioherbicides. In: Proceedings of the 5th International Weed Science Congress. Vancouver, BC, Canada, on CD-ROM, Abstract 393.
- Clayton, L.A. and D. C. Thill. 2008. Yellow mustard seed meals as bioherbicides. In: Proceedings of the Western Society of Weed Science. Anaheim, CA. Vol. 61. p. 37.
- Clayton, L.A. and D. C. Thill. 2007. Using Brassicaceae seed meals as bioherbicides in fresh carrot production. In: Proceedings of the Western Society of Weed Science. Portland, OR. Vol. 60 p. 52-53.
- Hansson, D., M.J. Morra, V. Borek, A.J. Snyder, J.L. Johnson-Maynard, and D.C. Thill. 2008. Ionic thiocyanate (SCN-) production, fate, and phytotoxicity in soil amended with Brassicaceae seed meals. J. Agric. Food Chem. 56:3912-3917.
- McClintick, J.W. 2008. The implications of mustard as an alternative break crop on the Palouse. M.S. Thesis, University of Idaho, Moscow, ID.
- McClintick, J.W. and L. Makus. 2008. Economic comparison of rotational effects between two break crops: Mustard and Peas in rotation with spring and winter wheat. Abstract published in J. Agric. Res. Econ. 33(3):489-490.
- Snyder, A.J. 2007. Brassicaceae seedmeals as soil amendments: Influence on nitrogen mineralization and plant growth. M.S. Thesis, University of Idaho, Moscow, Idaho.
- Snyder, A., M.J. Morra, J. Johnson-Maynard, and D.C. Thill. 2009. Seed meals from Brassicaceae oilseed crops as soil amendments: Influence on carrot growth, microbial biomass N, and N mineralization HortScience (in press).
|
Progress 12/15/06 to 12/14/07
Outputs
OUTPUTS: One student completed his M.S. degree in Soil Science. A second student is in the progress of finishing her degree in Plant Science. We made 2 presentations on our research at meetings and have had our plots as stops on two field-day tours. We completed the third year of a rotational study designed to determine if growing mustard in rotation with winter wheat and spring wheat produces a more sustainable rotation than the commonly used dryland winter wheat/spring wheat/pea rotation. We have completed data collection for variables including yields, weed densities, extractable and total nitrogen concentrations, earthworm populations, surface residues, carbon concentrations, microbial biomass, and soil bulk densities. We processed and analyzed soil samples collected in 2007 and are summarizing the data. In addition to completing the outlined analyses and assessments, we added a member (D. Shrestha) to our team to model energy inputs and outputs. Small plot research in which meal
was utilized as a biopesticide has been summarized and made ready for publication. One of our objectives was to investigate the influence of plant-available N and glucosinolate-derived allelochemicals released from the seed meals on strawberry establishment, vigor, yield, foliar N, and soil inorganic N. We completed the second year of this assessment. Data from a field study initiated to investigate the influence of Brassica juncea, Brassica napus, and Sinapis alba seed meals on carrot (Dacus carota L. var. sativus) growth and N mineralization has been summarized and will be submitted for publication in 2008. We also summarized our data on the environmental behavior of one of the responsible allelochemicals, SCN-. A draft publication has been written and will be submitted to a peer-refereed journal in 2008. In addition, we summarized our data on laboratory incubations using 15N-labeled Brassicaceae seed meals. We converted our provisional patent application entitled "Brassicaceae
Plant Materials and Method for their use as Biopesticides" to a utility patent. Negotiations are ongoing with commercial partners who have an interest in developing biopesticidal products from mustard meals.
PARTICIPANTS: Matthew Morra analyzed plant-derived allelochemicals and guided development of meal biopesticides. Donald Thill was essential in designing, conducting, and analyzing field studies related to weed control in the rotational and organic farming plots. Jodi Johnson-Maynard conducted nitrogen mineralization studies and phytotoxicity experiments with strawberries and carrots. Larry Makus collected and analyzed economic data related to the rotations and meal utilization. Joseph McCaffrey provided technical expertise on insect control. Dev Shrestha collected data to calculate an overall energy balance for biodiesel production.Graduate students Andre Snyder and Lydia Clayton participated in meal experiments to develop biopesticides and quantify nitrogen dynamics in soil. Andre Snyder graduated during this review period.
TARGET AUDIENCES: We interacted with organic growers, the target group for our biopesticides. We also interacted with agricultural products companies in an attempt to secure funding that will facilitate commercialization efforts of our biopesticides.
Impacts
Agroecosystems are experiencing additional pressure to produce not only food, but biofuels and bioproducts that will displace petrochemically derived materials. Although greater production of non-food bioproducts is essential for energy independence and is necessary to offset declining petroleum reserves, such production must be performed in a sustainable fashion. We cannot sacrifice long-term agroecosystem sustainability for short-term gains in biofuel feedstock production. We are taking a comprehensive approach to address managed ecosystems by concurrently optimizing the production of agricultural products and maximizing ecosystem services provided by dryland agroecosystems. Our goal is to develop a complete rotational scheme using an interdisciplinary approach that includes equal emphasis on the agricultural products and ecosystem services. We will further extend the value of the ecosystem services provided by the dryland rotation using some of the agricultural
commodities to promote and enhance organic and low input fruit and vegetable production. Decreased use of synthetic pesticides in both of the managed ecosystems will reduce potential negative human health impacts. Our work will be conducted with full consideration that all recommendations must be economically viable for grower adoption to occur. Successful completion will promote the development of entirely new industries related to biofuels and biopesticides production, thereby helping to revitalize agricultural communities. We are currently collecting the data necessary to integrate mustards into sustainable rotations, providing the data necessary to educate growers on the benefits. We have also developed biopesticides from mustard meal that will help displace synthetic pesticides, reduce environmental contamination, and protect human health. We are working on obtaining EPA registration of the mustard meals and are negotiating with commercial partners in order to bring products to
the marketplace.
Publications
- Thill, D., Morra, M., Johnson-Maynard, J., Makus, L., and McCaffrey, J. 2007. Managing a sustainable agro-ecosystem using mustard and mustard-by-products. British Crop Protection Council XVI International Plant Protection Congress. Glasgow, Scotland. 2 pg. Oct. 16.
- Snyder, A., Johnson-Maynard, J., and Morra, M. 2007. Abstracts of the 2007 International Annual Meetings of ASA-CSSA-SSSA.
|
Progress 12/15/05 to 12/15/06
Outputs
Our overall goal is to develop recommendations for managing more sustainable agricultural ecosystems by incorporating mustards into rotations and efficiently utilizing mustard seed-meal byproducts as soil amendments. We are addressing fundamental ecological questions as well as more applied aspects of mustard growth and seed meal utilization, thus filling data gaps that span the range from chemical ecology to agronomy. Our emphasis is focused on two managed ecosystems - one in which mustard is included as a rotational crop and the second in which mustard seed meal is used as a soil amendment in organic farming systems. A field study investigating the effects of Brassicaceae (Sinapis alba, Brassica juncea, and Brassica napus) seed meals on soil inorganic N, soil microbial community, weed growth, and physiological responses of strawberry and carrot was continued in the 2006 growing season. In the carrot study, all three varieties of seed meals increased soil inorganic N
concentrations and provided early season weed control relative to the unamended control. Carrot yields in the B. juncea and B. napus treatments increased by as much as 50% over the unamended controls, while S. alba treatments did not result in increased carrot yields. S. alba seed meal treatments inhibited carrot emergence relative to the control and the other seed meal treatments. Soil microbial biomass carbon and nitrogen in all seed meal treatments were significantly higher than in the control plots, and early measurements in B. napus treatments were significantly higher than those collected in S. alba and B. juncea plots. Ionic thiocyanate produced by the seed meals was extracted from the amended soils to determine the potential for this chemical to leach and to assess its residence time in soil. Ion chromatographic analyses are currently in progress. Strawberry yields from the June and July 2006 harvest were not different across all treatments. S. alba seed meal treatments,
applied in early August 2006, caused severe chlorosis in strawberry leaves, while B. napus seed meal treatments induced very slight chlorosis. B. juncea treatments did not cause any visual damage. Visual damage was not apparent in any new growth by late September. A laboratory mineralization study using N15-labelled seed meals is completed with data analyses underway. In our rotational studies, wheat following pea had a higher weed population than wheat following yellow or oriental mustard. This may be due to residual clopyralid applied in the 2005 mustard crops and/or secondary plant compounds released from the mustard into the soil. Plots were divided in 2006 to address the effect of residual herbicide. Sub-plots 6.5 by 11 m were sprayed or not sprayed with herbicide to compare the effect of rotational crop only in 2007. Wheat grain yield was not statistically different among rotational crops. Crop residue cover after planting on the at these plots was also determined. We have added
a new member to our team to address a complete energy balance for the production of biodiesel and the utilization of mustard meal in organic production systems.
Impacts
Mustard will be developed as a viable rotational crop in the Pacific Northwest, producing both oil for biodiesel and seed meal as a nitrogen fertilizer and biopesticide for use in organic agriculture.
Publications
- No publications reported this period
|
Progress 12/15/04 to 12/14/05
Outputs
An integrated approach that includes consideration of both the farm-level production process and ultimate uses of the crop and its byproducts must be employed when developing cropping strategies that are truly more sustainable, ecologically sound, and economically viable. Our overall goal is to develop recommendations for managing more sustainable agricultural ecosystems by incorporating mustards into rotations and efficiently utilizing mustard seed-meal byproducts as soil amendments. We will address fundamental ecological questions as well as more applied aspects of mustard growth and seed meal utilization, thus filling data gaps that span the range from chemical ecology to agronomy. Our emphasis is focused on two managed ecosystems: one in which mustard is included as a rotational crop and the second in which mustard seed meal is used as a soil amendment in organic farming systems. Both the rotational and organic plots were established in the fall of 2005. Seed meal
from the two mustards and a canola (Brassica napus) was amended to the soils at three rates and the crops were irrigated. Four different carrot plantings were performed to determine meal phytotoxicity. Data such as soil nitrogen content, soil bulk density, percent residue cover, weed counts, insect damage, and macroinvertebrate numbers were collected from the rotational plots. Parameters such as earthworm numbers will be used to determine what benefits accrue through the incorporation of mustards into typical dryland rotations. Organic plots were planted and similar chemical and biological data were collected. Mustard seed meal amended at the three rates (0.5, 1.0, and 2. 0 t ha-1) did not cause weed inhibition. Meal nitrogen may have enhanced weed growth and decreased any herbicidal effect. Marketable carrot yields were consistently higher when amended with 2 t ha-1 of B. juncea meal. This meal releases an isothiocyanate which may increase carrot yields. In summary, data are being
collected to comprehensively determine the potential of mustards to enhance agroecosystem sustainability. In addition to the topics discussed, economic data and a total energy balance will be determined.
Impacts
Mustard will be developed as a viable rotational crop in the Pacific Northwest, producing both oil for biodiesel and seed meal as a nitrogen fertilizer and biopesticide for use in organic agriculture.
Publications
- No publications reported this period
|