Location: Soybean/maize Germplasm, Pathology, and Genetics Research
2020 Annual Report
Accomplishments
1. Urbana ARS breeding lines with 25 to 62% exotic DNA were among the highest yielding maturity group IV lines in multistate cooperative evaluations in 2019. Genetic diversity among modern soybean cultivars is very limited and restricts the potential to increase yields and improve resistance to biotic and abiotic stresses. ARS researchers in Urbana, Illinois, developed genetically diverse breeding lines by crossing elite, high-yielding lines with plant introductions (PIs) from Asia. LG15-4655, LG15-4642, LG15-4634 and LG15-4644 were the highest yielding, and second, fourth and seventh highest yielding lines out of 19 entries in the 2019 Northern Maturity Group IV Uniform Test, respectively, with yields equal to or better than the best check line. Based on their pedigrees, each of these lines inherited 25% of its genes from the Chinese germplasm accessions PI 561319A and PI 574477. Line LG15-4348, with 62% exotic DNA, ranked ninth for yield in the test, but its yield was statistically equivalent to two of the three check lines. It has a unique pedigree and is derived from crosses with six soybean germplasm accessions and one accession of wild soybean (Glycine soja). All of these lines also had high yields in 2018. These results demonstrate the potential to increase genetic diversity in high-yielding soybean lines by combining genes from local elite parents and exotic germplasm, including wild and perennial Glycine accessions.
2. Breeding lines with exotic pedigrees and high yield met or exceeded a target of 48% meal protein and 11 pounds of oil per bushel in 2019. North American soybean processors desire soybean seeds with at least 47.5% meal protein and 10 pounds of oil per bushel. Due to a negative correlation between seed protein and seed yield and oil content in modern cultivars, increasing protein levels in cultivars derived from elite x elite crosses is seldom successful. In a collaborative project to circumvent this obstacle, ARS scientists in Urbana, Illinois, developed and selected breeding lines with at least 48% meal protein and 11 pounds of oil per bushel. In multistate evaluations of advanced breeding lines in 2019, four of the seven highest yielding entries in the maturity group (MG) III test (41 entries total) and six of the seven highest yielding MG IV lines out of 16 entries were Urbana ARS lines. These lines had also performed well in 2018. In preliminary multistate tests, four of the six highest yielding lines in a MG III test with 33 lines were Urbana ARS lines and eight ARS lines in a MG IV test out-yielded two of the three check lines, while still meeting the minimum protein and oil content criteria. The percentage of exotic germplasm accession DNA in these lines ranged from 3 to 65%, and about one-third of them had wild annual or perennial Glycine progenitors in their pedigrees. These results illustrate the potential to increase soybean seed protein without a concomitant decrease in yield by utilizing genes from accessions in the USDA Soybean Germplasm Collection that are absent from the narrow germplasm pool of modern North American cultivars.
Review Publications
Valquíria Dos Reis, M., Vaughn Rouhana, L., Sadeque, A., Koga, L., Clough, S.J., Calla, B., Duarte de Oliveira Paiva, P., Korban, S.S. 2019. Genome-wide expression of low temperature response genes in Rosa hybrida L.. Plant Physiology and Biochemistry. 146:238-248. https://doi.org/10.1016/j.plaphy.2019.11.021.
Zucchi, M.I., Cordeiro, E., Allen, K.C., Lamana, L.M., Viana, J., Brown, P.J., Omoto, C., Pinheiro, J., Clough, S.J. 2019. Patterns of genome-wide variation, population differentiation and SNP discovery of the red banded stink bug (Piezodorus guildinii). Scientific Reports. 9:14480. https://doi.org/10.1038/s41598-019-50999-z.
Zucchi, M.I., Cordeiro, E., Wu, X., Marise Lamana, L., Brown, P.J., Manjunatha, S., Gomes Viana, J., Omoto, C., Pinheiro, J., Clough, S.J. 2019. Population genomics of the neotropical stink bug, Euschistus heros: The most important emerging insect pest to soybean in Brazil. Frontiers in Genetics. 10:1035. https://doi.org/10.3389/fgene.2019.01035.
