Genetic yield stability in some sunflower (Helianthus annuus L) hybrids under different environmental conditions of Sudan

Abstract

Nineteen locally developed sunflower (Helianthus annuus L.) hybrids and an introduced one (Hysun 33) were evaluated at two irrigated locations, New Halfa and Rahad for two consecutive seasons (2003/04 and 2004/05) in order to estimate stability of performance for seed yield per ha (t). A randomized complete block design with four replicates was applied at each location. Data on seed yield was collected. The variance of genotype x environment interaction (GxE) was highly significant, suggesting that the yield of the hybrids was inconsistent in different environments. The average ranking of the 20 hybrids, according to stability parameters showed that Salih was the first ranked hybrid followed by Ka99x7, Ka99x29, Ka99x13 and Shambat 6, whereas Hysun33 was the last ranking one. The two released hybrids (Salih and Shambat 6) were adapted favorable environments, whereas Ka99x25-2 adapted unfavourable conditions. However, the graph for scatter points for yield of the locally developed hybrids revealed that Salih and Shambat 6 were stable, whereas that of Hysun 33 was unstable under these environments and its yield was only increased with improving the conditions. Key words: Sunflower, hybrids, yield, GxE interaction, stability.