Responses of Squash Plants to Different Foliar Concentrations of Phosphorus-potassium Compound Fertilizer

Because of the infertility characteristics of the new reclaimed lands in Egypt, this work was designed to investigate the effect of foliar application of a compound fertilizer (P-K) of phosphorus (as 25% P2O5 and 30% HPO3-2) combined with potassium (as 26% K2O and 21% K-) on squash plants (Cucurbita pepo) cv. Askandrany grown in the two successive seasons of 2008 and 2009 in Nubaria experimental farm. Plants were sprayed weekly starting at two weeks after seeding with different levels of P-K fertilizer namely 0.0 (control), 1.0, 2.0, 3.0 and 4.0 g/l. Results showed that as the concentration of spraying increased, plant growth parameters were enhanced i.e plant height, number of leaves, fresh and dry weights of shoots as well as number and total weight of fruits. The highest response was recorded with 3.0 g/l after which the response started to decline however still higher than control. It could be concluded that applying phosphorus in different forms combined with potassium improved squash growth, productivity and quality. Recorded data are further discussed with possible growth enhancing mechanisms involving nutrient contents.