Estimate of gene action for yield and polygenic yield related traits in bread wheat (T. aestivum L.) by using Hayman approach

摘要

Information about gene action involved in the inheritance of a character pays a key importance in any breeding program. Present study was carried out to determine the mode of gene action of polygenic yield related attribute in 5 x 5 diallel cross involving five wheat varieties namely Uqab 2000, Chenab 2002, Seher 2006, Millat-11 and Galaxy-13. The characters under studied were spike length, number of spikelets per spike, number of grains per spike, 100-grain weight, grain weight per spike and grain yield per plant. Highly significant differences were observed among genotypes for all the traits under consideration. It revealed that numbers of spikelet per spike and grain weight per spike were ruled by partial dominance with additive type of gene action therefore selection for improvement of these traits can be performed in early segregating populations. Over-dominance type of gene action was observed for number of grains per spike, 100-grain weight and grain yield per plant while non-allelic interaction was found to be present for spike length. Therefore selections for superior genotypes for these traits should be delayed until later filial generations.