STUDIES ON HYBRID WHEAT SEED PRODUCTION BASED ON TRITICUM TIMOPHEEVI CYTOPLASMIC MALE STERILE LINES

Abstract

A line X tester analysis of combining ability involving five male sterile (ms) lines of Indian cultivars and four exotic restorers of spring wheat revealed that 02 sca was higher than 02 gca for almost all the characters in both sets. Therefore gene action was found mainly non-additive type for these traits. In set II, 02 gea was higher than 02 sca for days to heading, duration of grain filling and plant height indicating additive gene action for these characters. Preponderance of non additive gene action was also indicated from 02 gcal02 sca which are less than unity for most of attributes. In set I, among lines, msUP 368 and msWH 157 for duration of grain filling, tillers/plant and spikes/plant; msHD 2204 for plant height; msUP 368 for days to heading and among testers, W8156 and 3401/478466 for duration of grain filling showed high gca effects. In set II, among lines, RJ-401 for days to heading and duration tillers/plant and spikes/plant showed high gca effects. It was observed that best general combiners were not always present in best specific cross combinations. The degree and direction of MP and SP heterosis varied greatly for different character and crosses. There was lack of definite relationship between sea effects and estimates of heterosis.