EFFECT OF DIFFERENT KINDS OF FERTILIZER ON GROWTH, PRODUCTIVITY AND QUALITY OF BROCCOLI CROP

Abstract

Experiments were conducted in sandy soil opened field at Nubaria, Egypt using drip irrigation system. The effect of bio, mineral and organic fertilizers and their interactions on the vegetative growth, mineral content of leaves, total heads yield, physical quality, nutritional value, antioxidant components and free radical scavenging activity of broccoli plants were studied. Five treatments of bio-fertilizers were applied using a mixture of nitrogen fixing and phosphorus solubilizing microorganisms (Aztobacterchroococcum, Bacillus megaterium,Arbiscularmycorrhizea, Bacillus polymyxa). In addition, four equations of mineral and organic fertilizers were applied. Mixture of Azotobacterchroococcum and Arbiscularmycorrhizea recorded the highest values of vegetative growth, leaves and heads mineral content (N, P, K, Ca and Mg), total heads yield, head physical quality (height, weight, diameter and number of stalks per head), dry weight, crude protein, total chlorophyll and total carotenoids contents. Equation of 75% mineral + 25% organic of the recommended fertilizer units exhibited the highest values of vegetative growth, leaves and heads mineral content, total heads yield, head physical quality, dry weight, crude protein, total chlorophyll and total carotenoids contents as compared to the other treatments. Equation of 25% mineral+ 75% organic of the recommended fertilizer units exhibited the highest values of antioxidant materials (total phenols, total flavonoids, vitamin C contents) and free radical scavenging activity. The combined effect of the two mixtures of Azotobacterchroococcum+Arbiscularmycorrhizea with 75% mineral+ 25% organic of the recommended fertilizer units recorded the highest values of vegetative growth, leaves and heads mineral content, heads yield, physical quality, dry weight, crude protein, total chlorophyll and total carotenoids contents as compared to the other treatments. Interestingly, the highest values of antioxidant materials and free radical scavenging activity were obtained by application of 25% mineral+ 75% organic of the recommended fertilizer units without bio-fertilizer addition. Key words: Broccoli; Bio-fertilizers; Mineral fertilizers; Organic fertilizers.