Effect of Irrigation Frequency on Cotton Yield in Short-Season Production Systems
- Chang-chi Chu ,
- Thomas J. Henneberry and
- John W. Radin
In irrigated desert areas of the southwestern USA, fruiting of cotton (Gossypium hirsutum L.) typically peaks in July. Water management during the fruiting period can influence cotton lint yields. This study tested the hypothesis that small frequent irrigations during the July peak fruiting stage would increase fruit set and yields compared with the same amount of water applied less frequently. During 3 yr under a short-season production system, irrigation intervals of 5-d with 42 mm of water applied at each of six irrigations increased lint yield by S to 11% compared with irrigation intervals of 10- and 15-d with 81 and 130 nun of water applied at each of three and two irrigations, respectively. Average stomatal conductance of 1989 and 1991 was higher for the 5-d-irrigation interval than for 10- or 15-d intervals. For 1990 and 1991 average leaf water potentials were higher and average leaf temperatures were lower for the 5-d-irrigation interval than for the other two irrigation intervals. The results show that with the same amount of water conventionally applied through furrow irrigation, small frequent irrigations during cotton fruiting were effective in reducing water deficit during critical growth stages and increasing lint production. The small frequent irrigations did not increase soil salt content in the top 15 cm of soil after 3 yr of study.
Copyright © 1995.