Back to Contents

FREE FULL TEXT PDF

GENE ACTION IN SOME YIELD ATTRIBUTES OF BREAD WHEAT UNDER TWO WATER REGIMES

GHULAM RABBANI^1*, ABID MAHMOOD¹, GHULAM SHABBIR² KAUSAR NAWAZ SHAH³ AND NAEEM-UD-DIN¹

Abstract: Breeders are always interested in the task of developing new varieties for changing environments. Thus, they have to deal with new crosses to select desired combinations. Grain yield is a complex character that is influenced by the fluctuating behavior of the environment. To overcome this situation, it is necessary to breed wheat varieties which perform better than existing ones under diverse conditions. A complete diallel cross was prepared from eight parental wheat accessions with a range of tolerance to drought. F₁ hybrids and parents were grown at Barani Agricultural Research Institute, Chakwal. At maturity peduncle length, number of spikelets per spike, number of grains per spike, dry weight per plant at maturity and harvest index were recorded.

Over-dominance genetic effects were important for the expression of number of spikelets per spike, number of grains per spike, dry weight per plant at maturity and harvest index under irrigated and rainfed conditions while additive type of gene action were important for the expression of peduncle length under irrigated and rainfed conditions. Average degree of dominance for peduncle length is 0.683 and 0.829 under irrigated and rainfed conditions respectively. Average degree of dominance for peduncle length was less than unity showing partial dominance and greater than unity showing over dominance in all characters under both irrigated and rainfed conditions.

¹Barani Agricultural Research Institute, Chakwal, Pakistan

²Department of Plant Breeding and Genetics, Arid Agriculture University, Rawalpindi, Pakistan

³COMSAT Institute of Information Technology, Islamabad, Pakistan.