Two field experiments were carried out in farmer fields during 2003 and 2004
summer seasons at 5herbeen, Dakhalia governorate to study the effect of UAN (Urea
ammonium nitrate, 32% N), agric. sulphur (5) and phosphorien (Biofertilizer)
application under recommended dose of NPK fertilizers (70 N + 30 P20S + 24 K20 kg
fed") on cotton plant growth, seed cotton yield, lint percent, oil content of seeds and
protein content of kernel seeds of the Egyptian cotton varieties Giza 86, G. 87, G. 88
and G. 89. The results indicated that: 1. The highest seed cotton yieldted" was realized from all varieties by foliar UAN
application under recommended dose of NPK (70 N + 30 P20S + 24 K20 kg fed"). Using phosphorien, UAN and 5 with NPK (70 N + 30 P20S + 24 K20 kg ted")
increased lint percent, plant height, No. of open bolls/plant, seed index and boll
weight in four cotton varieties. The study showed the vital importance of soil analysis, which indicated low levels of
available N, P, K and 5 and the soil must be fertilized with the economically
beneficial amounts of these nutrients when cropped with cotton. Protein, oil content in seeds and N, P and 5 contents fully developed leaves at the
beginning of flowering stage and were increased by using UAN, phosphorien and 5
treatments application. These clearly concluded' that UAN, phosphorien and 5 treatments could be used
with NPK (70 N + 30 P20S + 24 K20 kg fed") under the Egyptian conditions as
effective for improving seed cotton yield and quality of cotton varieties Giza 86, G.
87, G. 88 and G. 89. Meanwhile, these treatments lowered soil pH which resulted
in increasing ths availability of some nutrients as P and 5 in soil.