Heterosis and combining ability for grain yield and yield components in guinea sorghums

• Published in: African crop science journal Vol. 4; no. 4
• Main Authors: Toure, A, Miller, F.R, Rosenow, D.T
• Format: Journal Article
• Published: Uganda African Crop Science Society 31.12.1996
• Subjects: Aptitute a la combinaison; Combining ability; guinea; rendement; sorghos; sorghums; yield
• ISSN: 1021-9730; 2072-6589

Relatively low yields of guinea sorghums have been a major obstacle for sustained progress in yield improvement of the race in West Africa. In an attempt to determine why guinea sorghums of West Africa display low yield potential, seven converted guinea, four zerazera, and two caudatum sorghums were crossed to three improved A-lines. Parents and hybrids were evaluated for heterosis, general and specific combining at Halfway and College Station, Texas during 1989 and 1990. In general, non-guineas were better combiners than guineas for grain yield and most of yield components. Both additive and nonadditive effects for grain yield were observed among guinea parents. The additive effects of non-guineas for grain yield were higher than those of guinea parents. Guineas showed low additive effects for grain yield, number of seeds per panicle, and seed size. Guinea sorghums seem to maintain a relative low grain yield by reducing the number of seeds per particle and the seed size. Most hybrids of guineas showed positive heterosis over the best parent for grain yield. This is an indication that guineas do possess some genes or factors contributing to high yield expression.