Genetic and environmental drivers of legume cover crop performance: Hairy Vetch

Authors: Kucek, Lisa; Muller, Katherine; BASTOS MARTINS, LAIS - North Carolina State University; MOORE, VIRGINA - Cornell University; REBERG-HORTON, CHRIS - North Carolina State University; Mirsky, Steven; ENGLERT, JOHN - Natural Resources Conservation Service (NRCS, USDA); DRINKWATER, LAURIE - Cornell University; DOUGLAS, JOEL - Natural Resources Conservation Service (NRCS, USDA); EAGAN, SARAH - North Carolina State University; McGee, Rebecca; RYAN, MATT - Cornell University; CLARK, KERRY - University Of Missouri; EHLKE, NANCY - University Of Minnesota; HENDRICKSON, JOHN - US Department Of Agriculture (USDA); GURETZKY, JOHN - University Of Nebraska; WIERING, NICK - University Of Minnesota; HENRIQUEZ INOA, ESLEVTHER - North Carolina State University; WAYMAN, SANDRA - Cornell University; Archer, David; BARTOW, AMY - Natural Resources Conservation Service (NRCS, USDA); Burke, Allen; BARRETT, RICHARD - Natural Resources Conservation Service (NRCS, USDA); BERNAU, CHRISTOPHER - Natural Resources Conservation Service (NRCS, USDA); CASEY, ALLEN - Natural Resources Conservation Service (NRCS, USDA); LEE, STEVEN - Natural Resources Conservation Service (NRCS, USDA); HILLHOUSE, HEIDI - University Of Nebraska; SMITHER-KOPPERL, MARGARET - Natural Resources Conservation Service (NRCS, USDA); WIGGINS, DUSTIN - Natural Resources Conservation Service (NRCS, USDA); CARR, BRANDON - Natural Resources Conservation Service (NRCS, USDA); CRAWFORD, RYAN - Cornell University; BUTLER, TWAIN - Noble Research Institute; GRIFFIN, KIMBERLY - University Of Missouri; BULLARD, VALERIA - Natural Resources Conservation Service (NRCS, USDA); KROGMAN, SARAH - Noble Research Institute; MCGEE, NICHOLAS - Natural Resources Conservation Service (NRCS, USDA); SILVERMAIL, IAN - Natural Resources Conservation Service (NRCS, USDA); WAYMENT, JESSICA - Natural Resources Conservation Service (NRCS, USDA); Riday, Heathcliffe

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/22/2024
Publication Date: 9/22/2024
Citation: Kucek, L.K., Muller, K.E., Bastos Martins, L., Moore, V.M., Reberg-Horton, C., Mirsky, S.B., Englert, J., Drinkwater, L., Douglas, J., Eagan, S.S., Mcgee, R.J., Ryan, M.R., Clark, K., Ehlke, N., Hendrickson, J., Guretzky, J., Wiering, N.P., Henriquez Inoa, E., Wayman, S., Archer, D.W., Bartow, A., Burke, A.N., Barrett, R., Bernau, C., Casey, A., Lee, S., Hillhouse, H., Smither-Kopperl, M., Wiggins, D., Carr, B., Crawford, R., Butler, T., Griffin, K., Bullard, V., Krogman, S., Mcgee, N., Silvermail, I., Wayment, J., Riday, H. 2024. Genetic and environmental drivers of legume cover crop performance: Hairy Vetch. Crop Science. 64(6):3052-3072. https://doi.org/10.1002/csc2.21318.
DOI: https://doi.org/10.1002/csc2.21318

Interpretive Summary: Cover crops are typically grown in the times between seasons for cash crops like corn and soybean. Cover crops are desirable because they improve soil quality and reduce the need for chemical fertilizers. However, one of the major barriers to cover crop use is that the seed available to farmers is usually from unspecified seed that have uncertain and possibly undesirable traits. The Legume Cover Crop Breeding project (LCCB) is a nation-wide breeding program that is developing improved cover crop varieties tailored to various regions. Hairy vetch is one cover crop that shows promise as a nitrogen source for cash crops. This study presents results from hairy vetch variety trials in 50 environments (18 locations over 4 years) spanning contrasting regions in the US. All trials measured early growth, winter survival, and overall growth. A subset of trials measured the ability to provide nitrogen through symbiosis with root bacteria (symbiotic N fixation). The results identify hairy vetch lines that perform well in different regions. They also show that all lines were similarly good at symbiotic N fixation.

Technical Abstract: Among 50 environments in the United States, we screened 35 hairy vetch (Vicia villosa Roth.) lines for traits of interest to cover cropping. We analyzed the influence of genotype, environment, and the genotype-by-environment interaction (G × E) on biomass, vigor, winter survival, emergence, flowering time, and nitrogen fixation. To explore how environments and G × E impacted each trait, we associated environment predictions and G × E loadings with weather and soil parameters. Environment had the largest influence on all traits, representing more than half of the variance. Environment predictions were significantly associated with weather and/or soil parameters for each trait. Biomass was associated with growing degree days, winter survival with freezing degree days without snow cover, growth stage with shortwave radiation, and emergence with soil texture. The G × E interaction was larger than genotypic variance for all traits except for winter survival and flowering time. The G × E interaction loadings were associated with soil sand content for biomass, air temperature for fall vigor and emergence, and snow cover for winter survival. Although it represented the smallest proportion of total variance, genetic effects were significant for all traits except for emergence, Ndfa, %N, and C:N. New hairy vetch breeding lines were superior to all commercially available lines for biomass and winter survival. Biomass harvest timing did not significantly change line rank, indicating that top-performing lines can be used in diverse management systems. To select for high nitrogen contribution to subsequent crops, breeding programs can indirectly select for biomass rather than expensively evaluating symbiotic nitrogen fixation.