Registration of TifGP‐3 and TifGP‐4 peanut germplasm lines

Abstract

Late leaf spot (LLS) disease caused by Nothopassalora personata (Berk. & M.A. Curtis) U. Braun, C. Nakash, Videira & Crous is a foliar disease that plagues peanut (Arachis hypogaea L.) production worldwide. One effective solution to control this disease would be the development of resistant cultivars. IAC 322 is a breeding line resistant to LLS due to alien introgressions from A. cardenasii Krapov. & W.C. Gregory, a wild diploid relative of peanut. We crossed 'TifNV-High O/L' with IAC 322 to develop a segregating breeding population. Two lines with very high levels of resistance to LLS were selected and genotyped. Line S07 (TifGP-3, Reg. no. GP-244, PI 698818) has introgressed segments from A. cardenasii on the top of chromosome A02, the bottom of A02, and the bottom of A03. Line S273 (TifGP-4, Reg. no. GP-245, PI 698819) has the introgressed segments on the top of A02 and the bottom of A03. The level of resistance to LLS observed in these two lines was not significantly different. Segments on the top of A02 combined with the bottom of A03 accounted for the majority of LLS resistance. Some breeders may choose to use TifGP-4 to minimize the chance of linkage drag. However, important traits may reside in the segment on the bottom of A02, so we are also releasing TifGP-3. KASPar assays can be used to determine the presence or absence of each introgressed segment, which will allow breeders to use marker-assisted selection. These two germplasm lines were jointly released by the USDA-ARS and University of Georgia in 2021.

Marker-assisted introgression of wild chromosome segments conferring resistance to fungal foliar diseases into peanut (Arachis hypogaea L.)

“…By using marker-assisted selection, segments conferring RKN resistance were introgressed into released peanut cultivars ( Chu et al., 2011 ; Simpson et al., 2013 ; Clevenger et al., 2017b ). In addition, both by anonymous phenotypic and by marker selection, A. cardenasii -containing segments that confer resistance to leaf spots and rust have been introgressed into peanut in breeding programs worldwide ( Varshney et al., 2014 ; Shasidhar et al., 2020 ; Godoy et al., 2022 ; Holbrook et al., 2022 ). The very large-scale anonymous contribution of A. cardenasii to the peanut crop was recently shown with high-throughput genotyping; 251 peanut lines and cultivars in 30 countries were found to have genetics from this wild species; in almost all cases, the breeders involved were unaware of the wild genetics ( Bertioli et al., 2021a ).…”