پديد آورندگان :
الله قلي پور، مهرزاد نويسنده , , مريم حسيني ، مترجم ,
كليدواژه :
Hybrid rice , Line * Tester , general and specific combining ability , Grain yield
چكيده لاتين :
To determine the general and specific combining ability of the parental lines, four restorers and two male sterility lines were selected as lines and testers, respectively. Six parental lines were crossed in a Line x Tester crossing system in 2001. Eight F1 hybrids and their six parents were evaluated in a Randomized Complete Blocks Design (RCBD) with three replications for yield and yield components. After analysis of variance, the additive and dominant variances were calculated. Generally, parents with good combining ability produce good lines in the later generations. Therefore, the basic information about the general combining ability (GCA) and specific combining ability (SCA) is valuable tor breeding cultivars. The effect of GCA was significant for the number of grains per panicle, .plant height and days to 50% flowering in line No.l (IR60819R), which, indicated the importance of the additive gene effects for these traits. In line No.2 (IR68749R), the effect of GCA wasignificant for grain yield, 100-grain weight, plant height, days to 50% flowering and grain weight. The general combining ability of two testers was not significant for all characters. The effect of SCA was positive and significant for grain yield in hybrids of IR68281 A/1R60966R, IR58025A1 IR60819R and IR68281A IIR42686R. These hybrids had the highest grain yield with 8.030, 7.347 and 6.715 tlha respectively. Therefore, these combinations are recommendable for hybrid seed production after further tests in several environment.
