Effect of Bacillus megaterium var. phosphaticum applied together with rock phosphate on wheat yield and some soil properties in a calcareous soil

Abstract

This study aims to determine the effect of Bacillus megaterium var. phosphaticum applied together with rock phosphate on the yield of wheat grown in calcareous soil, some biological properties of soils and phosphorus fractions in the soil under greenhouse conditions. Considering the P fixation capacity of the soil used in the experiments and the amount of P present in the soil, the trial subjects were created based on randomized block designs with 3 replications, depending on whether 0, 25, 50, 75 and 100% of the P required to be given to the wheat plant was met from rock phosphate and whether it was bacterial or not, and finally wheat was grown. In the harvested plants, grain and stem weights were determined, grain and stem P contents were analysed and the amounts removed with grain and stem were calculated. Dehydrogenase (DHA) and phosphatase (PA) enzyme activities were performed in the soil samples taken after harvest. Soluble and loosely bound-P, Calcium-bound-P (Ca-P), Reductant soluble-P (RS-P) fractions and Olsen-P were determined in soil samples taken before planting and after harvest. The percent reduction in the fractions was calculated by using the pre-sowing and post-harvest values of these samples. According to the results, Bacillus megaterium DSM 3228 strain inoculated with rock phosphate increased grain and stem yield, grain and stem P content, and P amount removed by grain and stem of wheat. These parameters were found to be higher at high doses of P applied as rock phosphate. Inoculation increased the DHA and PA values of the soils. A decrease in P fraction forms with low solubility was determined by inoculation, some of this phosphorus was removed by plants and some of it was retained in the soil in different forms.