Interation Between Irrigation Initiation and Plant Density in sweet Corn

Abstract

Irrigation frequency and plant density directly influence variable costs of sweet corn (Zea may L.) production. Reduction in the number of irrigation can be achieved by delaying irrigation during growth stages. Responses of a seet corn to initiation of irrigation and plant density were investigated on a clay soil during November 1998 and February 1999 at Chai Nat Field Crops Research Center. The number of irrigation throughout the season was between 3 and 5, and total amounts of water applications were between 90 and 200 mm, depending up on timing of irrigation initiation. there were interactions in growth and yield between irrigation initiationand plant density. Leaf area index, leaf area duration and crop growth rate significantly decreased with delaying irrigation from V4 to V8 and VT, and reducing plant densities from 12,676 to 8,533 plants/rai. Irrigation initiated at V2 and V4 showed no significant differences in ear fresh weight (1,327-1,782 kg/rai), but irrigation intitiations at V8 and VT, respectively. when irrigation was initiated at V2 and V4, plant density of 12,767 plants/rai produced 10 and 26% greater ear fresh weight than plant densities of 10,683 and 8,533 plants/rai, respectively. If irrigation was initiated at V8 and VT, plant density of 12,767 plants/rai, but it gave 17-22% greater ear fresh weight than plant density of 8,533 plants/rai. Number of ears harvested and ear size were major yield components determining viely differences among irrigation initiations. A greater yield of the higher planting densities was mainly due to higher numbers of ears harvested.