Identification of parental combinations for improvement of rice grain quality, yield and yield components in rice

To determine the general and specific combining ability and identification of suitable combination for yield, yield components and grain quality characters, two improved (Saleh and Sepidrood) and eight traditional rice varieties (Hashemi, Abjiboji, Mohammadi, Hassani, Ahlamitarom, Hassansaraiee, Salari and Gharib) were selected as testers and lines, respectively. Ten parental lines were crossed in a Line×Tester crossing system in 2004. Sixteen F1 hybrids and their 10 parents were evaluated in a Randomized Complete Blocks Design (RCBD) with three replications for yield, yield components and grain quality traits. Results of variance analysis showed that crossing effect had significant differences for all characters in 1% probability level. It means, there is a good segregation between all genotypes based on the all traits. The effect of general combining ability (GCA) was significant for the panicle number, days to maturity, amylose content, grain length and total rice recovery in two testers. The effect of specific combining ability (SCA) was positive and significant for grain yield, panicle number and 100- grain weight in Sepidrood×Hassansaraiee combination. The results revealed that three combinations such as Sepidrood×Mohammadi, Saleh×Salari and Sepidrood×Gharib are suitable combinations for improving earliness maturity, dwarfing and high yielding rice varieties with good grain quality in rice breeding program, especially, the Sepidrood×Mohammadi combination is best one for these characters.