Growth and yield of upland cotton (Gossypium hirsutum L.) as affected by sowing dates and plant spacings.

摘要

A field experiment was conducted during the kharif season of 2001 and 2002 to study the effect of dates of sowing and plant spacings on growth and yield of American cotton. The experiment was laid out in split plot design with five sowing dates (February 25, March 15, April 5, April 25 and May 15) in main plots and three plants spacings (30, 45 and 60 cm) in sub-plots with four replications. In second year of study, February 25 date of sowing was deleted from the treatments. Highest seed cotton yield (21.9 and 30.7 q/ha) was recorded by March 15 sowing crop during both the years which was 64.7 and 30.6% more than that of crop sown on May 15. The crop sown on March 15 yielded more because of more number of sympodial branches and bolls per plant in earlier dates of sowings. Sowing dates of February 25, March 15 and April 5 were at par with each other but recorded significantly more yield than the later sowing dates of April 25 and May 15. Wider spacing, recorded more number of sympods and bolls per plant but no significant difference was noted among the three spacings tested for seed cotton yield on per unit area basis.