The effects of plant population and water level on drip irrigated cotton

Abstract

The fruiting pattern and yield of drip irrigated cotton (Gossvoium hirsutum L.) were studied in relation to irrigation level and planting rate. Two irrigation treatments, 100 and 80% of consumptive use represented by 30.4 and 24.1 ha cm water per season were studied with two planting rates; 5.6 and 22.4 Kg ha⁻¹, at Eloy, AZ. The field was uniformly irrigated from 25 April to 10 June, 1985. Irrigation treatments, however, were initiated on 11 June. The lowest mainstem node with a sympodial branch supporting a boll was one node higher at the 22.4 kg ha⁻¹ seeding rate treatment. In addition, the number of monopodial branches per plant was significantly decreased with increasing seeding rate or decreasing water application rates. Increasing planting rate did not significantly increase yield. Significant yield increases were detected with increasing water application. The interaction effects between water and seeding rate were not significant for yield. While no significant difference in the total number of bolls produced at the end of the season was detected, the weight of the bolls were significantly increased with increasing water and/or decreasing seeding rate.