COMBINING ABILITY EFFECTS OF SOME PHENOLOGICAL TRAITS IN BREAD WHEAT

Five wheat varieties/lines viz. Chakwal-97, Inqlab-91, GA-2002, 6C001 and 6C002 were crossed in 5 x 5 diallel cross to estimate combining ability at PMAS Arid Agriculture University, Rawalpindi, Pakistan during 2007-2008 and 2008-2009. GCA effects for days to heading (7.81), flag leaf area (22.07), plant height (82.18), number of tiller metre -2 (2997.21), days to maturity (9.59) and grain yield plant -1 (47.76) were non-significant indicating the preponderance of non additive type of gene action for these traits. SCA effects were highly significant for days to heading (26.81), flag leaf area (365.11), plant height (141.05), number of tillers metre -2 (8639.21), days to maturity (18.85) and grain yield plant -1 (93.70) which indicated that these traits are being controlled by non-additive type of gene action. RCA effects were also highly significant for all the traits studied suggesting selection can be effective in later generations. Chakwal-97 proved to be the best general combiner for all the characters under study except plant height. Among hybrids, Chakwal-97 x 6C002 proved better having maximum SCA for days to heading, number of tillers metre -2 and days to maturity while hybrid Chakwal-97 x Inqlab-91 had higher SCA for 1000 grain yield plant -1 . Hence it can be concluded that Chakwal-97 may be used in breeding programmes to develop high yielding wheat cultivars.