Studies on Combining Ability and Heterosis for Yield, Its Components and Some Grain Quality Traits in Rice Using Line X Tester Under Normal and Water Deficit

Abstract

Combining ability and heterosis were studied on 15 F1 hybrids and their parents to understand the inheritance of yield, its components and some grain quality traits for selecting superior genotypes. A line x tester mating design was conducted during 2021and 2022rice seasons at the Experimental Farm, of Sakha Research Station Kafr El-Sheikh, Egypt. The results revealed that GCA and SCA were highly significant for all studied traits except grain shape under both conditions. 11 L236 genotype was the best general combiner for number of days to 50% heading, number of filled grains/panicle, sterility% and grain yield/plant under normal and water deficit conditions. Also Giza 178 was the best general combiner for number of panicles/plant, grain yield/plant and hulling % under both conditions while, IR6500-127, Giza 178 and GZ1368-S-5-4 for head rice % and for amylose content Lines 11 L236 and tester Nerica7 under both conditions were good combiners for this trait. Crosses IR 69432 x Nerica7, IR 69432 x GZ1368-S-5-4, IR 12G3213 x Giza178, IR 12G3222 x Giza178 and IR 12G3222 x Nerica7 had high and significant SCA in desirable direction for most studied traits under both condition. Crosses IR6500-127 x Nerica7, 11 L236 x GZ1368-S-5-4, IR69432 x Nerica7, IR 12G3213 x Nerica7, IR 12G3222 x GZ1368-S-5-4 and IR 12G3222 x Nerica7 exhibited highly significant and desirable estimates of heterosis as a deviation from mid and better parent for most studied traits under both conditions.