Abstract
Irrigation schedules I1 (six irrigations), I3 (irrigation at 25 mm potential soil moisture deficit) and I4 (irrigation at 50
mm potential soil moisture deficit) increased seed cotton yield by 79.23%, 80.26% and 81.70%, respectively over
I2 (three irrigations) during 2003 and 79.19%, 80.20% and 81.65%, respectively during 2004. It was mainly due to
the increase in total dry matter production (TDM) in former than the later. Increasing rate of integrated plant
nutrition levels significantly enhanced seed cotton yield and TDM over control and lower rates of integrated plant
nutrition. Integrated plant nutrition level N5 (150-75-75 kg NPK ha-1 + FYM @ 20 t ha-1) increased seed cotton
yield by 53.63% in 2003 and 53.69 % in 2004 over control that was followed by N6 (150-75-75 kg NPK ha-1 +
wheat straw @ 5 t ha-1) which gave higher seed cotton yield (35.49% in 2003 and 35.50% in 2004 over control) in
comparison to the rest of integrated plant nutrition levels. The seed cotton yield was strongly dependent and
related to the total dry matter production since there was a positive and linear relationship between them. Higher
TDM production in I4 (irrigation at 50 mm potential soil moisture deficit) or in other higher integrated plant nutrition
levels was due to higher crop growth rate in these treatments. Analyzing crop growth and yield in terms of leaf
area duration (LAD) and yields, a strong and positive linear relationship was found.
