Effect of sowing dates and fertilizer levels on phenology, growth and yield of cotton

A field experiment was conducted during 2001–02 cropping season with dates of sowing as main plot treatments and fertilizer levels as sub-plot treatments. Hybrid NH44 did not show a significant difference in yield and yield attributing characters either at higher or lower level of fertilizer as compared to recommended dose. Delayed sowing, after 20^th July on the other hand significantly reduced the yield. Both boll weight and number of bolls per plant contributed for the yield reduction. Late sown crop could not develop a full canopy surface area that is required to receive and use maximum of incoming solar radiation due to low temperature induced growth reduction at squaring and flowering. The heat units needed to produce open bolls from flowers were significantly reduced in late sown crop under rainfed condition.