Genetic variability and heterosis among rice genotypes for yield and yield associated traits
By: Muhammad Ismaeel, Syed Mehar Ali Shah, Akhtar Nawaz, Zakria Bacha, Aziz Ur Rehman, Said Suliman
Key Words: Rice, Genotypes, Genetic variability, Heterosis, Heritability
Int. J. Biosci. 9(2), 137-146, August 2016.
The present research was performed to assess genetic variability and heterosis among 30 rice genotypes for yield and yield associated traits. Sixteen F1 hybrids and their 14 parents were planted in a randomized complete block design using two replications at The University of Agriculture Peshawar, during 2011 rice crop growing season. Highly significant differences among the parents and F1 hybrids were observed for all the traits studied. The parental genotypes Bas-370, Pakhal and IR-8 displayed maximum values for panicle length (32.5 cm), primary branches panicle-1 (15.1)and secondary branches panicle-1 (47.0), respectively. Among the F1 cross combinations, IR-8/Sugdesi manifested higher mean values for primary branches panicle-1 (15.0) and secondary branches panicle-1 (55.0) whereas Bas-6129/Bas-370 showed maximum value for panicle length (34.0cm). Moderate and low phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for most of the traits. High broad sense heritability values were observed for all the studied traits except primary branches panicle-1.Bas-2008/Kashmir-Bas showed the highest positive values of mid and better parent heterosis for primary branches panicle-1 (33.3 and 19.0%) while Bas-2008/Kashmir-Bas and Dokri-Bas/Bas-6129 for secondary branches panicle-1(44.2% and 30.6%), respectively. On the basis of superior performance for yield and yield associated traits, the parental genotypes IR-8 and Pakhal whereas the F1 hybrids IR-8/Sugdesi and Bas-2008/Kashmir-Bas are recommended for onward use in rice hybridization programs.