Genetic Studies on the Photothermo Sensitive Genic Male Sterility (Ptgms) and Its Utilization in Rice Breeding.

Abstract

Studies of heterosis and combining ability of six photo /thermo-sensitive testers were estimated using line x tester analysis for some agronomic characters and yield and its components to get useful information for two-line system in hybrid rice breeding in Egypt .The outstanding hybrid combinations for grain yield plant -1 were PTGMS-5/Dular (45.26%) with significant standard heterosis for ,panicle length (28.22%) productive tillers plant -1 (24.19%) ,panicle weight (26.93%) ,filled grains panicle -1 (25.89%),spikelets panicle -1 (14.19%) ,spikelet fertility % (10.20% ) and 100-grain weight (35.62% ) .In the mean time ,PTGMS-14/Norin PL9,PTGM-7/Dular ,PTGMS-14/Giza178 and PTGMS-5/Giza 178 were considered as promising hybrids.Among the six PTGMS lines,PTGMS-5 and PTGMS-14 were the best general combiners for grain yield and all studies characters.The testers , Dular , Giza178,M202 and Pecos were the best general combiners among testers for grain yield and most studies characters.