Nitrogen Accumulation by Pepper as Influenced by Mulch and Time of Fertilizer Application

Abstract

Peppers ( Capsicum annuum L.) were grown during 2 seasons on Blichton fine sand (Arenic Plinthic Paleaquult) to evaluate the effects of black polyethylene mulch and timing of N application on accumulation of applied N by the shoots and fruit. Nitrogen was applied at 224 kg/ha as 15-N depleted (NH 4 ) 2 SO 4 in a split application or in a single application with and without mulch. During a relatively dry season, total fruit yields and N accumulation were not influenced by treatment. At the end of the crop season, N accumulation from the 224 kg N/ha averaged 16.5% in the shoots, 2.2% in the immature fruit, and 15.8% removed in the harvested fruit for a total utilization of 34.5% (77 kg/ha). The soil supplied about 43 kg N/ha. During an extremely wet season, fruit yields and N uptake were influenced significantly by treatments. Fruit yields were 25.1, 5.5, and 17.5 T/ha with the mulch, no-mulch single, and the no mulch split application treatments, respectively. Total N utilizations by plant shoots, immature fruit, and harvested fruit were 41.8% (94 kg/ha), 7.6% (17 kg/ha), and 23.9% (54 kg/ha) of the applied N with the 3 treatments, respectively. Nitrogen quantities utilized from the soil with the 3 treatments were 27, 11, and 15 kg N/ha, respectively.