IMPROVEMENT OF PRODUCTION AND QUALITY OF GARLIC UNDER WATER STRESS CONDITIONS

Abstract

The field experiment was carried out during the two growing seasons of 2013/2014 and 2014/2015, at the farm of Faculty of Agriculture, Ain Shams University, Shoubra El-Kheima, Egypt, to investigate the effect of irrigation at different percentage of available soil water depletion, soil conditioner, foliar application of glycine betaine and potassium silicate on vegetative growth, bulbs yield and its components as well as chemical composition of garlic (Allium sativum L.), cv. Sids- 40. The experimental treatments were arranged in a split split plot design with three replicates. The applied irrigation levels (55-60, 70-75 and 85- 90%) were assigned in the main plots, soil conditioner at the rates of 2 m3/Fed and control were distributed in the sub-plots and foliar application of glycine betaine was used at 2 mM/L, potassium silicate was used at 0.5 g /L and control (sprayed with distilled water) were devoted in the sub- sub plots. Irrigation treatments were started after six weeks from planting, foliar application of glycine betaine and potassium silicate started after 50 days and repeated for 6 times at 15 days intervals Results indicated that the irrigation after depletion of 55-60% available soil water with applying soil conditioner and foliar application of glycine betaine or potassium silicate increased the bulb fresh weight, leaf fresh weight, plant length, leaf area and leaf chlorophyll reading of garlic as well as the yield of bulbs, cloves fresh weight/bulb, cloves number/bulb, bulb diameter, Neck diameter, bulbing ratio, average clove weight, nitrogen content, protein and total carbohydrates content. While, prolin content, catalase activity, total soluble solids, ascorbic acid, phenols and total sugars were significantly increased as a result of irrigation after depletion of 85-90 % available soil water without applying soil conditioner.