ABSTRACTS OF PAPERS PRESENTED AT THE 1948 MEETINGS OF THE GENETICS SOCIETY OF AMERICA

Abstract

WILLIAMSL, . F., U. S. Regional Soybean Laboratory, Urbana, Illinois: Inheritance in a species cross in the soybean.-In fifteen crosses between the domestic soybean (Glycine hispida (Moench) Maxim) and the wild soybean (Glycine ussuriensis Regel and Maack), seed size was found to be geometric in inheritance. Neither the large size of the domestic parent nor the small size of the wild parent was recovered in over 4000 FZ plants nor in the first backcross generation. In the BCISl and in the BC2 the size of the larger recurrent parent was recovered. The percentage of oil was about intermediate in the F1, but neither the high oil content of the domestic parent nor the low oil content of the wild parent was recovered in the Fz generation. The protein content of the F1 was very close to that of the wild (high) parent, and some Fz segregates had even a higher protein content. The F1 had the prostrate and vining habit of the wild parent, and the erect habit of the domestic parent was not recovered in the FZ or FS generation or in the BC1. The maturity of the F1 in most cases was intermediate to the parent, but in Fz transgressive segregation in both directions was observed. Most of the strains of the wild soybean appear to have a chromosomal arrangement different from the domestic type and resulting in approximately 50 percent abortive pollen and ovules in the F1 generation, but certain plants in T106 gave normal pollen and ovules in crosses with the domestic type. The wild type evidently carries the gene G for green versus yellow seed coat, but this is obscured by the black coat of the wild type.