EFFECT OF SHEEP MANURE, PHOSPHORUS LEVELS AND CHEMICAL FERTILIZERS AS WELL AS BIOFERTILIZERS ON GROWTH, YIELD, NITRATE ACCUMULATION AND CHEMICAL COMPONENTS OF BROCCOLI (Brassica oleracea var italica) PLANTS

Abstract

Two field experiments were carried out on broccoli (Brassica oleracea var italica) plants cv. Premium to study the effect of sheep manure at the rate 10 m3 ( 4.28 tons/fed.), 3 levels of phosphate fertilizer i.e. 0, 10 or 20 kg P2O5/fed.or the recommended rate of chemical fertilizers (40 N + 30 P2O5 + 50 K2O kg/fed.) with three kinds of biofertilizers i.e. yeast, Pseudomonas, Bacillus (bacteria dissolving phosphate) inoculated with seedling or uninoculation on vegetative growth characters at head initiation and at side head initiation as well as days from transplanting until head initiation, yield and chemical components in leaves and heads. Applying sheep manure plus 20 kg P2O5/fed. followed by sheep manure plus 10 kg P2O5/fed. gave higher values of plant length, plant, stem, leaves fresh weights, number of leaves per plant, head, side heads weights per plant and total yield/fed. as well as the percentage of N, P, K,dry matter, total sugar, soluble phenols and total free amino acids concentration in leaves and heads comparing with adding recommended chemical fertilizers. Days from transplanting until head initiation not affected by fertilization. The result indicated that using sheep manure plus 10 kg P2O5 gave better values than using chemical fertilizers. On the other hand, ascorbic acid of heads was higher by adding sheep manure plus10kgP2O5 than values of sheep manure plus 20 kg P2O5 or chemical fertilizers. Nitrate content of heads were the highest with application chemical fertilizer. The three biofertilizers treatments increased vegetative growth parameters, total yield and its components as well as chemical components in the leaves and heads as comparing with uninoculation treatment. Pseudomonas aeruginosa resulted in the highest yield of heads in the first season also side head weight and total yield per fed. as well as total sugars and amino acids in leaves in both seasons . Yeast caused the higher values of heads yield per fed. and total free amino acids in heads, in the second season. On the other hand, nitrate content of heads were the highest with inoculated plants with yeast, while Bacillus caused the lowest values. Bacillus results in the highest total amino acids in heads in the first season and ascorbic acid content in heads in both season.The highest total yields were obtained of plants received sheep manure plus 20 kg P2O5/fed and inoculated with pseudomonas or Bacillus in the first and second seasons, respectively.