Effect of Foliar Spraying with Liquid Organic Fertilizer, some Micronutrients, and Gibberellins on Leaf Mineral Content, Fruit Set, Yield, and Fruit Quality of “Hollywood” Plum Trees

Abstract or Introduction

This investigation was carried out during 2007 and 2008 growing seasons on “Hollywood” plum trees, grown in loamy clay soil condition at Sendyon village, Kalubia governorate, Egypt; Aiming to study the effect of foliar sprays with Aminofert (20% Amino acids, 12% organic acids, and 3.6% chelated micro-elements), gibberellins, and a mixture of chelated (Fe, Zn, and Mn) alone or in combination (GA3 + Aminofert or GA3 + a mixture of chelated “Fe, Zn, and Mn”)on fruit set, yield, fruit quality, and leaf mineral content. Treatments increased significantly fruit set, yield as weight; or number of fruits/tree, as well as, fruit characteristics (Firmness, TSS, Flesh thickness, and Acidity) were improved under all treatments as compared to the control. Gibberellins or Aminofert alone or in combination (GA3 + Aminofert or GA3 + a mixture of chelated “Fe, Zn, and Mn”) applied to foliage caused a pronounced increase in leaf N, and K content; while Leaf P content decreased in both experimental seasons. As for micro-nutrients concentration, the data indicated that the concentration of Fe, Zn, and Mn was icreased in all treatments comparing to the control. Application of Aminofert at 0.25% + GA3 at 20 ppm was more effective compared to other treatments in the two seasons.