Sixteen genotypes of T. aestivum L. were tested under abundant and limited supply of water and fertilizer with varying dates of sowing. With the differences due to variations in water and fertilizer input, the genotypes displayed variation from 22.3 to 55.4 q/ha in grain yield of wheat and 20.1 to 54.8 cm2 in flag leaf area. The flag leaf area (FLA) of different genotypes was found to be highly associated with the grain yield. However, UP 270 and WL 903, which attained very high FLA (47–55 cm*) did not display this relationship.
With the delay in sowing time from 15th November to 15th December, a significant reduction (27.9%) in grain yield as well as FLA (13.0%) was recorded. A positive correlation (0.955) was observed between the grain yield and the FLA under different dates of sowing. On the other hand, the grain yield and the FLA increased significantly from 26.2 to 40.8 q/ha and 24.7 to 30.5 cm2, respectively with the addition of two post sowing irrigations as compared to the results from no post sowing irrigation. The correlation between yield and FLA was significant (0.964) as influenced by irrigation treatments.
