Two field experiments were carried out at the Research Farm of El-Gemmeiza Agric. Res. Station, El-Gharbia Governorate during 2018 and 2019 seasons, to study the effect of four NPK fertilizer rates (the recommended NPK rate (100%) serving as a control, 75%, 50% and 25% of the recommended NPK rate), foliar spraying with vermicompost extract at three levels (0, 5 cm 3 /L and 7.5 cm 3 /L) at three times (at 30, 45 and 60 days from sowing) and their interaction. The experimental design was a strip plot with four replicates in both seasons. The important results indicated that increasing NPK rate from 25% to 100% significantly increased leaves chemical composition and resulted in a significant increase in growth traits, earliness traits, yield and its components in both seasons and significantly increased fiber length and strength in one season. Fiber uniformity and fineness did not affect.Foliar application with 7.5 cm 3 /L vermicompost extract significantly increased leaves chemical composition and recorded a significant increase in growth traits, earliness traits, yield and its components in both seasons, except number of total flowers plant-1 and fiber strength which significantly increased in one season. Fiber length, uniformity index and fineness did not affect in both seasons.Regarding the interaction effect, data show that the best results were obtained from the high level of vermicompost extract (7.5 cm 3 /L) combined with 100% NPK. It could be concluded this combination under El-Gemmeiza condition, to increase cotton productivity through soil fertility especially in vigor's cultivar like Giza 86.

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This study was conducted during two successive seasons (2019 and 2020) on cotton cultivar Giza 86 at El-Gemmeiza Agricultural Research Station, El-Gharbia Governorate, Egypt, to study the effect of foliar feeding with two compounds enriched with phosphorus and potassium [Agrophytex at two levels (2 and 4 cm 3 /L) and potassium phosphate at two levels (2 and 4 g /L)] either alone or in combination at the low and high level compared to the control treatment (sprayed with tap water and fertilized with phosphorus and potassium at the recommended rates as soil application) on cotton productivity and quality. A randomized complete blocks design with 4 replicates was used. The obtained results revealed that foliar feeding with Agrophytex and potassium phosphate combination at the two levels examined significantly increased percentages of N, P, K and contents of chloroplast pigments in cotton leaves in 2019 season. Growth parameters, earliness measurements, seed cotton yield/feddan and its components in both seasons as well as micronaire reading and fiber strength in the second season were also increased. Whereas, boll shedding percentage decreased. Fiber length and uniformity index did not affected. It could be concluded that using combination of Agrophytex and potassium phosphate at the low level (2 cm 3 Agrophytex + 2 g potassium phosphate)/L four times (at seedling stage, squaring initiation, flowering start and peak of flowering stage) as alternative to soil P and K fertilization was recommended to reduce cost, overcome P and K fixation and obtain high productivity under conditions similar to El-Gemmeiza region.