Native Pseudomonas spp. suppressed the root-knot nematode in in-vitro and in-vivo, and promoted the nodulation and grain yield in the field grown mungbean

Publication date: Available online 13 July 2016 Source:Biological Control Author(s): Mujeebur Rahman Khan, Fayaz A. Mohidin, Uzma Khan, Faheem Ahamad The study describes the effects of Pseudomonas aeruginosa, P. fluorescens, P. stutzeri and P. striata on root nudulation (Bradyrhizobium sp.), root-knot disease (Meloidogyne incognita), and on the plant growth and yield of field grown mungbean (Vigna radiata). In vitro the Pseudomonas spp. produced hydrogen cyanide (P. fluorescens), ammonia, siderophore and indole acetic acid, and solubilized phosphorus. The bacterial cells and cell free culture filtrate of Pseudomonas spp. suppressed egg hatching and induced mortality to the juveniles of M. incognita with overall greater effects of P. fluorescens and P. striata. The seeds of mungbean cv. T-44 treated with Pseudomonas spp. (1011-12 colony forming units/ ml) and Bradyrhizobium (109-10 CFU/ml, 5 ml/kg seeds) were sown at 45 spots in every field plots (4 x 2 m) with or without the nematode inoculation of 2000 juveniles/spot. In the plots without nematodes, grain yield and NPK acquisition of mungbean plants were significantly higher with P. fluorescens or P. striata treatments (P⩽0.05). The Pseudomonas treatments synergized with Bradyrhizobium sp., leading to significant enhancements in the root nodulation, leghemoglobin contents, and the population of rhizobia in the nodule as well as in the soil. The nematode infection caused severe galling on the roots and decreased...
Source: Biological Control - Category: Biology Source Type: research