Phosphorus nutrition of drip irrigated cotton

Abstract

The effect of phosphorus (P) fertilization on drip irrigated cotton (Gossypium hirsutum L.) was studied in 1984 on a Trix clay loam classified as fine-loamy, (calcareous), hyperthermic, Typic Torrifluevent. The objectives of this study were to relate P fertilization to the P concentration in plant tissues, P uptake and cotton yield under drip irrigated conditions. Growth analysis data and total phosphorus in plant tissues were obtained at specific sampling intervals from both P and non-P fertilization treatments in a replicated field study. Moreover, flowering pattern, flower abscission and boll production were studied. Fertilizer treatments were arranged in a Randomized Complete Block design with N, NP, NPK and NPKZn treatments. Rates of N, P, K and Zn fertilizers were 175.4, 44.8, 88.6 and 2.58 kg/ha, respectively. Application of P in this field experiment did not increase P content in plant tissues and did not increase dry matter production, P uptake, and cotton yield significantly, but there were consistant trends toward increased dry matter, P uptake, and cotton yield in the P treated plots. Soil test for P before application of P fertilizer showed enough phosphorus was available in that particular soil for cotton production.