A New Soybean Variety "Yumeyutaka" lacking both L-2 and L-3 of the LipoxygenaseIsozymes

Abstract

A new soybean cultivar named Yumeyutaka, registered as Soybean Norin 97, was developed by the National Agriculture Research Center (NARC) in 1992. It is nearly isogenic to the widely grown cultivar Suzuyutaka, but differs in the lack of the two lipoxygenase isozymes, L-2 and L-3 in its seeds. Yumeyutaka was selected from a cross of a BC3F3 Iine lacking L-2, Suzuyutaka (4) x PI 86023 and a BC4F2 Iine lacking L-3, Suzuyukata (5) x Wasenatsu. The recurrent parent Suzuyutaka has all the lipoxygenase isozymes called L-1, L-2 and L-3, and is highly resistant to soybean mosaic virus (SMV) and moderately resistant to soybean cyst nematode (SCN). The donor parents PI 86023 and Wasenatsu are the mutant soybeans lacking L-2 and L-3, respectively. Yumeyutaka is similar to Suzuyutaka in all visible traits such as determinate stem, purple flower, gray pubescence, broad leaves, brown pods and dull whitish-yellow seeds with yellow hila of medium size. It is classified into the Maturity Group 111 . In performance trials in the fields of NARC and Tochigi Prefectural Experim.ent Station, the average seed yield during the period from 1989 to 1991 was 5% Iess than that of Suzuyutaka, while the protein and oil contents were similar to Suzuyutaka. It is resistant to SMV and SCN.