Plant Stand Density and Row Configuration Effect on Production of Texas Pinkeye Hull Cowpea

Abstract

In the Texas Rolling Plains (northwest Texas), cowpea [Vigna unguiculata (L.) Walp.] is often considered a replacement crop following early-season cotton (Gossypium hirsutum L.) failure. A 3-year field experiment using a 6x2 factorial in a randomized complete block design was conducted to determine the optimum row spacing and planting density for maximum production of Texas Pinkeye Purple Hull Cowpea. Factor A consisted of six plant stand densities: 0.5, 0.6, 0.8, 1.1, 1.5, and 1.8 plants/sq ft whereas, factor B consisted of 1 or 2 rows (spaced 40 inches or 12 inches apart, respectively) on beds formed 40 inches apart. Seed yield was higher with two rows per bed than one row per bed and was highest (754 lbs/ac) at 1.5 plants/sq ft. This was significantly higher than 1.1 plants/sq ft or lower densities. Seed yield was closely related to pods/sq ft. Pods per plant were higher with two rows per bed than with one row per bed and decreased with increasing plant stand density. Seeds per pod were not affected by either row spacing or plant stand density. Pea weight was only slightly affected by plant stand density. This study found that a yield of about 900 pounds per acre may be achieved with 70,000 plants per acre, planted in two rows per bed and an average within row spacing of 5 inches. Pod density or pods/sq ft was an important regulator of seed yield, whereas seeds per pod and seed weight remained relatively constant.