Progress 09/01/12 to 08/31/16
Outputs
Target Audience:Organic corn, soybean, wheat and peanut farmers were the target audience for our project along with county extension and other agricultural professionals who advise them. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?We hold a winter conference each year to discuss progress with the farmers and get feedback. Our partner organization Rural Advancement Foundation International hosts a session where farmers who participated in one of the advanced line trials on-farm get to talk about their favorites. This year, a session will be dedicated to on-farm hybrid corn production for the new double cross hybrid we have released. In July of each year, we host a summer field day where our advanced line trial is held and farmers can see firsthand how new lines are performing relative to commercial checks. How have the results been disseminated to communities of interest?Seeds from several of these commodities will soon be available commercially as detailed in the accomplishments section. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Corn Three years ago, NC State began a collaboration with the University of Guadalajara to identify new sources of Dominant Gametophytic Factors (DGF's). That collaboration has been highly successful and has resulted in our ability to provide new source of pollen blockage to breeders around the country. Our aggressive shipment of these seeds to other public breeders and publication of the new DGF's was done to prevent patenting of these genes at the request of our University of Guadalajara colleagues (Jones et al 2016; Sanchez et al. 2011). We also collaborated with NIFA on a press release for the most recent publication, https://www.cals.ncsu.edu/agcomm/news-center/perspectives/block-that-pollen/. These new DGF's are now sufficiently within the public domain to prevent easy patenting. In North Carolina, we continue to work on new hybrids that take advantage of these new crossing barriers. We have also continued to pursue double cross hybrids for organic corn because of the reduction in seed production costs when seed must be produced organically. Our best hybrid seed was produced on three farms in North Carolina for the farmers to grow their own seed and to be able to sell to their neighbors. All three farmers were new to hybrid corn seed production but will continue to produce this seed in 2017. Several of our hybrids are being pursued for acquisition by private seed companies and will be available commercially within the next two years. Soybeans We have developed protocols to screen soybeans for competitiveness with weeds. Multiple methods of measuring soybean canopies were tested to predict their competitive ability (Place et al. 2011a). Directly measuring competitive ability, as done in this study, is extremely expensive as it involves growing the crop in competition with weeds and then separating crop and weed biomass to assess the outcome. Fortunately, one of the techniques, overhead image analysis of the soybean canopy combined with pixel counting software, was sufficiently predictive to allow it to serve as an indirect measure of competitive ability. We utilized this approach to screen 45 entries chosen to represent as wide a range in growth patterns as possible (Figure 1, adapted from Place et al. 2011a and Place et al. 2011b). Heritable variation in competitive ability is present in soybean and we have used these results to screen germplasm from the national soybean collection and our advanced lines from the USDA NC soybean breeding program. For the last three years, we have combined this screening approach with an ultra-narrow row production of soybeans (row spacing at 4.5"). The genetic differences in weed competitiveness are even more pronounced in the ultra-narrow rows. Unfortunately some competitive genotypes are more prone to lodging in these rows, but some genotypes could be found that were both competitive and lodging resistant. Two manuscripts are in preparation from this work and are currently published in the M.S. thesis of Jeremy Machacek available electronically at NC State libraries. Three new soybean lines have been released to North Carolina Foundation Seed in conjunction with this project. We have one year from this spring to apply for PVP protection for the cultivars if we can find a sufficient number of seedsmen interested in producing them. Peanuts Although the Southeastern USA has more peanut production and exportation (http://www.ers.usda.gov/Data/StateExports/) than any other region in the country, most organic peanut production occurs in New Mexico and West Texas (http://www.ers.usda.gov/Data/Organic/). Southeastern organic growers would like to add this crop to their rotation, but seedling diseases have presented a seemingly insurmountable problem (Ruark and Shew 2010; Kokalis-Burelle et al. 1997). Stand reductions of over 50% have been observed in our on-farm trials. Gaps in the peanut stand allow weeds to become established and can make the entire field impossible to harvest with a peanut digger. Since the advent of efficacious fungicidal seed treatments, peanut breeders have not had a reason to select for resistance to seedling diseases because the treatments are cheap, effective, and strongly recommended in conventional production practices (Spears et al. 2002). We have developed assays to screen old lines and exotic germplasm. Seedling diseases affecting peanut are of the genera Aspergillus, Fusarium, Pythium, and Rhizoctonia. As with any assay, providing uniformity of pressure from these organisms is key to finding genetic variation. Innoculating with Fusarium produces little disease while our Rhizoctonia assay is perhaps too aggressive. Aspergillus and Pythium have been more successful and are being used to screen hundreds of genotypes from the peanut genotype core collection. Resistant lines are fed into two breeding approaches. One of those approaches is a mass selection program where the peanuts are grown in the absence of fungicides. Highly susceptible genotypes do not survive to reproduction, providing a low labor approach to selection. Peanuts harvested from this field each year are screened for seed size to maintain the large seed trait and replanted the following year. Since this method produces far more seed than we need, each years newly improved population is made available to farmers. Several have continued to plant the updated seed each year with germination rates showing signs of improvement. Wheat The limiting factor for organic wheat production in the Southeast is Italian ryegrass (Weisz et al. 2013). Once this non-native weed becomes well established in an organic field, wheat must be removed from the rotation. Research was initiated in fall 2010 to: a) identify protocols for screening wheat genotypes for competitiveness with ryegrass in field trials and b) to evaluate genetic diversity in eastern US wheat varieties for allelopathic activity against ryegrass (Lemerle et al. 2001). Allelopathic wheat lines exude chemicals from their roots that prevent the germination and growth of weeds (Spruell 1984; Wu et al. 2000). Wheat to rye biomass ratio prior to harvest was correlated with various visual, spectral signal and overhead photography measurements taken during the growing season. The number of ryegrass heads per square meter was highly correlated with biomass ratio and early growth pattern during the October to March period influenced ryegrass growth (Worthington et al. 2013) We trialed 60 cultivars and advanced lines two years in a row to screen for ryegrass suppression. The best genotype from that experiment (Featherstone VA258) suppressed ryegrass by 44% (Worthington et al. 2015). Considering the minimal cost to farmer of switching varieties, this additional tool in the fight against ryegrass can be instantly adopted by growers. We have continued to refine exactly what traits make the most competitive wheat. Molecular marker searches have revealed that day length sensitivity genes are the most correlated, more evidence that early to elongate in the spring varieties with a highly erect habit are the most competitive. Selection for these traits is possible while still maintaining a medium maturity wheat that will not risk late frosts. Two manuscripts are in preparation from this work and are currently published in the M.S. thesis of Matthew Granberry available electronically at NC State libraries.
Publications
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Progress 09/01/12 to 08/31/13
Outputs
Target Audience:Organic row crop producers and buyers. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?We hold mutliple meetings per year with farmers. A mid July tour is held to look at the organic trials of the advanced soybean lines. Farmers get to walk the fields and make their own comments about the entires. At the last field day, one of the farmers who had hosted an advanced line trial on his farm shared his experience with one. He had found a line with cotyledons further up the stem than usual that made cultivation easier. This trait had previously gone unnoticed in our tests. In February, we hold a workshop to discuss breeding progress and advanced line results from all four crops, corn, soybeans, wheat and peanuts. How have the results been disseminated to communities of interest?Findings are primarily disseminated on our websitehttps://organicgrains.ces.ncsu.edu/ When new results are published, farmers and educators receive an email and/or tweet depending on what format they have selected. Our subscribers now spand most of the southeastern states. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Three years ago, NC State began a collaboration with the University of Guadalajara to identify new sources of DGFs. That collaboration has been high successful and has resulted in our ability to provide new source of pollen blockage to breeders around the country. Our aggressive shipment of these seeds and publication of the new DGF's was done to prevent patenting of these genes at the request of our University of Guadalajara colleagues (Jones et al 2016; Sanchez et al. 2011). We also collaborated with NIFA on a press release for the most recent publication, https://www.cals.ncsu.edu/agcomm/news-center/perspectives/block-that-pollen/. These new DGF's are now sufficiently within the public domain to prevent easy patenting. We have developed protocols to screen soybeans for competitiveness with weeds. Multiple methods of measuring soybean canopies were tested to predict their competitive ability (Place et al. 2011a). Directly measuring competitive ability, as done in this study, is extremely expensive as it involves growing the crop in competition with weeds and then separating crop and weed biomass to assess the outcome. Fortunately, one of the techniques, overhead image analysis of the soybean canopy combined with pixel counting software, was sufficiently predictive to allow it to serve as an indirect measure of competitive ability. We utilized this approach to screen 45 entries chosen to represent as wide a range in growth patterns as possible (Figure 1, adapted from Place et al. 2011a and Place et al. 2011b). Heritable variation in competitive ability is present in soybean and we have used these results to screen germplasm from the national soybean collection and our advanced lines from the USDA NC soybean breeding program. Although the Southeastern USA has more peanut production and exportation (http://www.ers.usda.gov/Data/StateExports/) than any other region in the country, most organic peanut production occurs in New Mexico and West Texas (http://www.ers.usda.gov/Data/Organic/). Southeastern organic growers would like to add this crop to their rotation, but seedling diseases have presented a seemingly insurmountable problem (Ruark and Shew 2010; Kokalis-Burelle et al. 1997). Stand reductions of over 50% have been observed in our on-farm trials. Gaps in the peanut stand allow weeds to become established and can make the entire field impossible to harvest with a peanut digger. Since the advent of efficacious fungicidal seed treatments, peanut breeders have not had a reason to select for resistance to seedling diseases because the treatments are cheap, effective, and strongly recommended in conventional production practices (Spears et al. 2002). We have developed assays to screen old lines and exotic germplasm. Seedling diseases affecting peanut are of the genera Aspergillus, Fusarium, Pythium, and Rhizoctonia. As with any assay, providing uniformity of pressure from these organisms is key to finding genetic variation. Innoculating with Fusarium produces little disease while our Rhizoctonia assay is perhaps too aggressive. Aspergillus and Pythium have been more successful and are being used to screen hundreds of genotypes from the peanut genotype core collection. Resistant lines are fed into two breeding approaches (details in methods section). The limiting factor for organic wheat production in the Southeast is Italian ryegrass (Weisz et al. 2013). Once this non-native weed becomes well established in an organic field, wheat must be removed from the rotation. Research was initiated in fall 2010 to: a) identify protocols for screening wheat genotypes for competitiveness with ryegrass in field trials and b) to evaluate genetic diversity in eastern US wheat varieties for allelopathic activity against ryegrass (Lemerle et al. 2001). Allelopathic wheat lines exude chemicals from their roots that prevent the germination and growth of weeds (Spruell 1984; Wu et al. 2000). Wheat to rye biomass ratio prior to harvest was correlated with various visual, spectral signal and overhead photography measurements taken during the growing season. The number of ryegrass heads per square meter was highly correlated with biomass ratioand early growth pattern during the October to March period influenced ryegrass growth (Worthington et al. 2013) We trialed 60 cultivars and advanced lines two years in a row to screen for ryegrass suppression. The best genotype from that experiment (Featherstone VA258) suppressed ryegrass by 44% (Worthington et al. 2015). Considering the minimal cost to farmer of switching varieties, this additional tool in the fight against ryegrass can be instantly adopted by growers.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Jones, Z. G., Goodman, M. M., & Krakowsky, M. D. 2016. Identification of maize-derived dominant gametophyte factors. Euphytica (Ahead of Print, DOI 10.1007/s10681-016-1635-0)
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Jones, Z. G., Goodman, M. M., & Krakowsky, M. D. 2015. Identification of resistance to the Ga1-m gametophyte factor in maize. Euphytica 206:785-791.
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Worthington, M., S.C. Reberg-Horton, G. Brown-Guedira, D. Jordan, R. Weisz, and J. P. Murphy. 2015. Morphological Traits Associated with Superior Weed Suppressive Ability of Winter Wheat against Italian Ryegrass. Crop Science 55:50-56.
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Worthington, M., S.C. Reberg-Horton, G. Brown-Guedira, D. Jordan, R. Weisz, and J. P. Murphy. 2014. Relative Contributions of Allelopathy and Competitive Traits to the Weed Suppressive Ability of Winter Wheat Lines against Italian Ryegrass. Crop Science 55:57-64.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Worthington, M.L. and S.C. Reberg-Horton. 2013. Breeding cereal crops for enhanced weed suppression: optimizing allelopathy and competitive ability. Journal of Chemical Ecology 39:213-231.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Worthington, M.L., S.C. Reberg-Horton, D. Jordan, and J.P. Murphy. 2013. A comparison of methods for evaluating the suppressive ability of winter wheat cultivars against Italian ryegrass (Lolium perenne). Weed Science 61:491-4999.
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