Sixty-six families of sunflower were ivestigated for their genetic response under two different sowing dates al the School of Biological Sciences. University of Birmingham. England. The results showed significant differences for flowering time, height at flowering and area of head set with seed in both sowings. However. more significant genetic variations were detected in normal sowing compared with late sowing.

Significant effect of genotype x sowing interaction on the family performance suggested that a good agreement exists between family means across sowing for all the traits. A low magnitude of corelations, however, indicated that low genetic variation exists among families.

Negative correlations between H6 and flowering time revealed that early flowering and short plants flower earlier than slow growing plants. Critical association between flowering time and Sclerotinia infection, an epidemic disease of sunflower in EC countries, further evidence that early flowering and short plants are attacked more than tall and late flowering families. Thus, normal sowing during the first fortnight of May is the optimum time for obtaining good yield because it attained maturity before the onset of severe wet weather in September.