ANALYZING COMBINING ABILITY AND HETEROSIS OF THERMOPHOTO SENSITIVE GENIC MALE STERILE WHEAT LINES FOR HYBRID DEVELOPMENT

This study was conducted to identify desirable wheat germplasm for superior hybrid cross combinations through 1) identifying the best parents with high combining ability (CA) and 2) estimating heterosis effects. Two thermophoto-sensitive-genic-male-sterile lines (K456s and K78s) as female parents and 60 restorer lines as males were crossed according to line × tester hybridization method. The observed variation for most of the nine studied characters and <1 ratio for general (G)/specific (S) CA suggested governance of non-additive gene action. The GCA for K456s was higher than K78s in six out of nine characters, while restorers 2016Y2-2776 and 2016Y2- 4117 had the highest in five characters. The crosses K78s/R31 and K456s/R2 had highest positive SCA values in five and six characters, respectively. The crosses K78s/R43 and K456s/R21 had the overall highest significant positive heterosis estimates for the best cross with respect to yield plant-1and has the potential for utilization in hybrid wheat breeding program.