Studying the Genetic Mechanism of Some Yield Contributing Traits in Wheat (Triticum aestivum)

Diallel mating system was used to evaluate seven wheat varieties including five cultivars from Pakistan viz. Inqilab-91, Shalimar-88, Chenab-2000, Uqab-2000, Punjab-85 and two from CIMMYT naming Weebli-1 and Maya/Pavon. These were crossed in diallel fashion to get 42 cross combinations including direct and reciprocals. Significant differences were observed among genotypes for all the traits. Scaling tests were used to test the adequacy of the data for analyzing additive-dominance model, which showed that additive-dominance model was fully adequate for plant traits like number of grains per spike and grain yield, but characters like tillers per plant, spike length and 100-grain weight showed partial adequacy of the data. The D component for all the traits was significant showed that all the characters are additively controlled. The Vr-Wr graphs showed over dominance for number of grains per spike, while partial dominance was observed in traits like plant height, tillers per plant, 100-grains weight and grain yield per plant. © 2010 Friends Science Publishers