Effectiveness of Bacillus subtilis, B. pumilus, Pseudomonas fluorescens on Meloidogyne incognita infecting cowpea

Abstract

Under screen house conditions, this experiment was conducted to investigate the effectiveness of single or combined application of bacterial inoculation of Bacillus subtilis (Bs), B. pumilus (Bp) and Pseudomonas fluorescens (Pf) on M. incognita, infecting cowpea cv. Baladi. Based on average percentages of nematode reduction, P. fluorescens (Pf) achieved (89.0%) followed by the combined treatments of Pf+Bs (88.5%) and Pf + Bs + Bp (86.3%) as compared to untreated positive and negative controls. As for cowpea vegetative growth, the highest plant growth increase (69.0%) was observed in combined treatment of Bs+Bp followed by 55.6% in single treatment of Pf and the least plant growth was obtained in combined treatment of Pf + Bs + Bp (54.8%). The highest percentage of yield increase (70.2%) was recorded in Bs+Bp treatment followed by 49.3% by B. pumilus (Bp). The highest percentage (116.7%) in the number of bacterial nodules on roots of cowpea was obtained by the combined treatment Pf + Bp, followed by the combined treatment Bs + Bp i.e. 88.9%. The combined treatments of Bs + Bp and Pf + Bp were responsible for increasing phenolic and soluble proteins, respectively. The effects of combined treatments of Pf+Bs and Pf +Bp were recorded for highest contents of photosynthetic pigments than the other treatments either as single or combined treatments.