Effect of the Biofertilizer (Bacillus Megaterium) and the Addition of Yeast Spraying on the Vegetative Growths in Phosphorous Availability, Growth and Yield of Onions (Allium Cepa L.)

Abstract

A field experiment was carried out in clay mixture soil according to the randomized complete block design with three replicates in one of the College of Agricultural Engineering Sciences / University of Baghdad fields. The study aims to identify the effect of the biofertilizer (Bacillus megaterium) and the addition of yeast on the availability of phosphorus, the yield, and the growth of onions after adding 50% of the fertilizer recommended for phosphorus. The study results showed the superiority of Bacillus megaterium treatment in the phosphorous availability, yield, vegetative growth and phosphatase enzyme activity (7.444 mg.kg-1, 0.540%, 0.298%, 35.521 μg), respectively. In comparison, the treatment of not adding Bacillus megaterium gave an average of (4.113 mg.kg-1, 0.363%, 0.198%, and 23.740 µg) respectively. Also, the results of the interaction between Bacillus megaterium and yeast showed the superiority of the treatment of adding yeast spraying to the vegetative part in the concentration of phosphorous in the soil. Besides, the yield, the vegetative part, and the activity of phosphatase enzyme (5.925 mg.kg-1, 0.480%, 0.292%, 32.483 μg), respectively, compared to the treatments of no yeast addition (5.630 mg.kg-1, 0.423%, 0.205%, and 26.778 μg). Keywords: Biofertilizer, Yeast, Soil, Onions