Production and Performance of Hybrid Soybeans1

The quest for hybrid cultivars in self‐pollinated crops has been encouraged by the great success achieved in hybrid corn (Zea mays L.). However, because past research has relied on hand pollinations to produce hybrid seeds in soybeans [Glycine max (L.) Merr.] very little is known about the performance of hybrid soybeans. The objectives of this study were to look for heterosis in seed yield of soybean hybrids and to compare other characteristics in the hybrids with those of the parents. All hybrid seeds in this study were produced using genetic male sterility and insect pollination. The experiments were grown at Urbana, III. in a Flanagan silt loam (Aquicarguidoll) and Belleville, 111. in an Ebert silt loam (Argiaquicargialdoll), in 1977 and 1978. Agronomic data were collected from 27 hybrid combinations grown in replicated, bordered plots. Five hybrids yielded significantly more (13 to 19%) than their better parent in at least one season. Only one hybrid exceeded the yield of the best pure‐line cultivar in the test. The yield performance of the hybrids could not be predicted from their pedigrees. Several hybrids significantly exceeded the height of the taller parent, but, with few exceptions, no high‐parent heterosis was observed for maturity date, lodging score, harvest index, seed quality, seed weight, oil percentage, or protein percentage. Significant heterosis was observed even though relatively few hybrids were tested and the parents were unselected for combining ability. The inability to produce large quantities of hybrid seeds economically is the major barrier to the use of commercial hybrid soybean cultivars.