Yield of Successively Cropped Polyethylene-mulched Vegetables as Affected by Irrigation Method and Fertilization Management

Abstract

Broccoli (Brassica oleracea L. var. italica), followed by tomato (Lycopersicon esculentum Mill) or squash (Cucurbita pepo L. var. melopepo), and then broccoli were produced in succession re-using the same polyethylene-mulched beds at two locations with different soil types. First-crop broccoli yield was earlier and greater with drip than with overhead irrigation and increased as N-K rate increased from 135-202 to 270-404 kg·ha-1. On a tine sandy soil, yields of second and third crops produced with residual or concurrent fertilization increased with an increase in N-K rate. On a loamy fine sandy soil, yields also increased as the rate of residual N-K increased; yields of second and third crops did not respond to rate of concurrently applied N-K, but were higher with concurrent than with residual fertilization, except total tomato yields were similar with either application time. With drip irrigation and concurrent weekly fertigation, yields equalled or exceeded those obtained with preplant fertilization and overhead irrigation.