Composite–Sibbed Line Methods and Their Potential Use in Sweet Corn Hybrids

Abstract

The waxy, inbred line was crossed onto two inbred lines and one single cross of shrunken, super-sweet corn. They were then backcrossed onto the corresponding super-sweet parents. Following consecutive selfing up to BC₁S₄, 15 ears from each BC₁S₄ family were selected and then transformed
into composite–sibbed lines by four different methods: consecutive selfing within family line (SFL), topcross within line (TCL), selective mass sibbing within line (MSL) and recurrent–sibbed line (RSL). Based on seed yield per se as the selection criterion, MSL and RSL were more effective than the other two methods. However, seed yield of the parent and the selection method did not imply the quality of fresh yield in the corresponding hybrid. Occasionally, some of the high seed yield lines from MSL and RSL not only gave high fresh-ear yield hybrids, but also an exceptional quality of fresh ears. The results reflected the possibility of using a composite–sibbed line method to improve the yield and quality of parent lines in sweet corn which could then be transmitted to the corresponding single cross hybrids.