Estimation of Genetic Variability in Relation to Heterosis and Combining Ability of Wheat from Subtropical and Temperate Zones

Abstract

A fter maize in terms of production, wheat is the cereal grain with the second-highest global trade volume. It is the main crop and is regarded as the king of all cereal crops due to its ease of production, ecological suitability and great nutritional value. It is particularly rich in proteins (7-22%), carbohydrates, Abstract | The mechanism of genetic improvement for yield of food crops have become highly important for the plant breeders. It has been used for selection of suitable parents for true development of the hybrids. The current research was carried-out to determine heritability, general combing ability (GCA) and specific combing ability (SCA) during (Rabi Season 2018-19) at Directorate of Oilseed Crops, ARI Sariab, Quetta, Balochistan. The research trial was arranged in a Randomized Complete Block design (RCBD) with three repeats. The results from analysis of variance exhibits significant differences at (p<0.001 and 0.005) for all studied parameters. In hybrids, Benazir×Raskoo had the highest average value (92%) and in parents, TD-1 (89.66%) found best among hybrids. Similarly, correlation coefficient results indicated significant association among all genotypes for all characteristics. Most of the parameters among crosses showed highly positive significant heterosis. Similarly, parents and their crosses were significant for all the 14 parameters studied. It is concluded from this study, among parental lines Raskoo and TD-1 are good general combiner for the traits plant height, No. of tillers plant -1 , Harvest index, Spike density, spikelets spike -1 , Grains spike -1 , Fresh weight, Dry weight, Flag leaf area, thousand grain weight, Grain yield plant -1 and Tones per hectare as showed highly significant positive general combining ability, respectively. While among TD1 × Benazir and Umeed × Raskoo were observed as good specific combiner crosses in all parameters. Further, it is recommended that these genotypes be further included in breeding program to get more cultivar and hybrids combiner to enhance yield through yield contributing traits with additive genes and for further development of yield and yield related traits.