Mixing Ability To Identification of Superior Biblends Through Inter genotypic Competition of Bread Wheat Triticum aestivum L

Abstract

Abstract :A study conducted a program of exchange half diallel program of nine pure lines of wheat as Griffing second modified method (1956) by a mixing ratio(1:1) to obtain 36 dimixing combination, these genotypes (pure lines, doubled combination and the certified variety of sham 6) were sown in R.C.B.D experiment with three replications in Alhawija region (southern west of Kirkuk) during winter season of 2009- 2010 to study mixing ability which also studying of mixing ability for growth characters ( assimilation efficiency , relative growth rate , leaves area ratio, and duration of highest leaf area) and number of days to 50% flowering, plant height and yield and its components (length of spike ,number of grains in a spike ,weight of 1000 grains, and number of effective tillering ) and density of spikes , weight of grain g/m2 ,biological yield and harvesting index ) the results are summarized as follows: Mean squares of general mixing ability were highly significant for all characters except number of effective tillering, biological yield and relative growth rate, while mean squares of specific mixing ability were highly significant for all characters except relative growth rate , spike length , weight of 1000 grains, spikes density , biological yield and harvest index .The strains ( 5 , 7 , 8 and 9 ) showed significant general mixing ability in desired direction for some characters, while doubled combinations (1+5 ), (1+8),(2+5),(2+9) and (3+6) showed significant specific mixing ability in desired direction for some studied characters.