Updated February 26, 2020:
Chen Lab:
Released lines: We have released 12 high yielding lines with resistance/tolerance to Phytophthora root rot from 2016-19 (S13-10590, S13-10592, S13-1955, S15-10434, S11-16653, S12-4718, S11-20242, S13-2743, S13-3851, S14-15146, S14-9017, S14-15138). Among those, three lines (S13-2743, S13-3851, S14-9017) carry Rps-1 alleles and eight of them have been licensed to private companies for commercialization.
Advanced lines: In the 2019 USDA Uniform Tests, four of our lines (S15-3772RY, S16-16641R, S16-11651C, S15-17812C) were found to carry Rps 1a resistance gene while another (S15-3847RY) was found to carry Rps 1c gene in hypocotyl and layer tests conducted in Dorrance Lab in 2019. These lines also showed high yield performance (S15-3847RY = 63 b/a, 113% of checks; S16-11651C = 62 b/a, 112% of checks; S15-17812C = 60 b/a, 102% of checks; S15-3772RY = 59 b/a, 101% of checks; and S16-16641R = 55 b/a, 98% of checks) across multiple locations.
In the 2019 USDA Uniform Prelim Tests, two lines (S09-13608C and S17-19874R) were found to carry Rps 1a gene while another line, S16-14161C carries Rps 1c gene. S16-14161C had yield of 69 b/a and ranked 1st among 16 test entries. Lines S09-13608C and S17-1984 had yield of 63 b/a and 59 b/a, respectively and ranked 5 and 12, respectively.
A total of 40 new high yielding lines have been selected for 2020 USDA Uniform tests and will be screened for resistance in hypocotyl and layer tests conducted in Dorrance Lab in 2020.
Breeding lines in the pipeline: A total of 64 crosses were made in 2018 involving 5 high-yielding lines carrying Rps genes are now under generation advance in winter nurseries in Costa Rica and Puerto Rico. F4:5 lines will be tested in progeny rows in 2020 for selection of promising lines. Nine RILs carrying different novel Rps genes and breeding lines S13-2743C, S15-3772RY, S15-17812C and S15-3847RY carrying Rps genes, were used in crossing with elite lines in 2019 season. A total of 22 new crosses were made and the F1 are being under light in the winter nurseries for generation advance, and the F4:5 lines are expected to return home station in 2021 for evaluation.
Wang Lab: In spring 2019, a total of six crosses were made in the greenhouse between two resistance lines, carrying the QDRLs identified in Dr. Anne Dorrance’s group and three high yielding lines, E14077, LD02-4485, and LD10-10198. The F1s were grown in the MSU research farm in summer of 2019 and the F2 seeds were harvested and were planted in the greenhouse in the fall of 2019. The populations will be advanced for two generations in 2019-2020 winter to F3:4. Molecular markers developed by Anne Dorrance’s group will be used to screen the F3 plants for individuals carrying the resistance QDRLs. The selected F3:4 will then be planted in our single-row plots in 2020 for initial field evaluations.
In the summer of 2019, additional seven crosses between seven new resistance lines from Dr. Anne Dorrance and an MSU high yielding line, E15339, were made. These F1 seeds will be planted in 2020.
Maroof and Robertson Labs. A major QDRL to P. sylvaticum, P. irregulare, and P. torulosum was identified on chromosome 8 in an advanced RIL population developed in the Maroof lab. In addition, several minor QDRL to P. sylvaticum, P. irregulare, and P. torulosum were identified in 4 advanced RIL populations developed in the Maroof lab and the soybean NAM resource. These are the first QDRL to be identified for resistance to P. oopapillum, and P. torulosum.
Dorrance and McHale Labs. Select RILs with novel resistance to one or more soilborne pathogen were provided to the breeders for germplasm and variety development in 2019. Based on new maps and markers, another set of RILs will be provided to the collaborators for additional crosses in 2020.