Abstract
Breaking of yield stagnation through novel approaches like exploitation of gene pools of winter wheat and
spring wheat as well as new variability available in the form of buitre & synthetic wheats is one of the promising
avenues for ensuring food security. However, very little information is available on their combining ability.
Therefore, to assess the combining ability of yield and secondary traits among these important gene pools, 18 F1
hybrids developed by (6x6) half diallel of two winter, two spring, one facultative and one buitre parents were
evaluated in replicated plots over 2 years. Highly significant differences among the six parental lines for all
attributes suggested that sufficient variability existed in this set of material. Non-additive gene effects
predominate for all the characters. The larger magnitude of GCA compared to GCA x Year mean squares,
suggests that interaction effects may be of relatively minor importance for days to heading, ear length, spikelets
per ear, grains per ear, grains wt. per ear and 1000 grain weight. The spring wheat ‘UP 2572’, facultative wheat
‘VL 818’ and buitre line ‘CMH 83.2518’ can be used as parents for high grain yield per plant. On overall basis
‘90 Zhong 65’/ ‘HW 3083’ a winter x spring cross was the best cross combination having desirable significant
GCA effect for days to heading, maturity, ear length, grain weight per spike, grain yield per plant, biological
yield per plant and thousand grain weight. Although GCA effects of the most of the winter, spring, facultative
and buitre wheats were average for yield as such but they were good for one or other yield component and their
combination can produce improved genotypes. The chances of getting high yielding genotypes were high
through winter x spring followed by winter x facultative and spring x buitre as compared to other crosses.
