Response of Cotton Cultivar Giza 90 NPK Application Levels

Abstract

The present investigation was carried out at Shandaweel Agriculture Research Station during 2005 and 2006 seasons to study the effect of NPK application levels on growth and seed cotton yield as well as its components of the Egyptian cotton cultivar Giza 90 (Gossypium barb dense L.). A randomized complete blokes design with four replicates was used. Nine treatments were as follows: NPK0 : 45 kg N + 15 kg P2O5 + 0 kg K2O/ fed NPK1 : 45 kg N + 22.5 kg P2O5 + 24 kg K2O/ fed NPK2 : 45 kg N + 30 kg P2O5+ 48 kg K2O/ fed NPK3 : 60 kg N + 15 kg P2O5 + 0 kg K2O/ fed NPK4 : 60 kg N + 22.5 kg P2O5 + 24 kg K2O/ fed NPK5 : 60 kg N + 30 kg P2O5 + 48 kg K2O/ fed NPK6 : 75 kg N + 15 kg P2O5 + 0 kg K2O/ fed NPK7 : 75 kg N + 22.5 kg P2O5 + 24 kg K2O/ fed NPK8 : 75 kg N + 30 kg P2O5 + 48 kg K2O/ fedThe results of these experiments indicated that plant height at harvest, Number of fruiting branches/ plant, height of fruiting nodes, number of open bolls/ plant, boll weight, seed cotton yield/ plant and feddan were significantly increased by tested treatments in both seasons. The greatest values of these traits were obtained from the combined fertilization with 75 kg N + 30 kg P2O5 + 48 kg K2O/fed.