Fortified bacterial consortium - A novel approach to control root knot nematode in cucumber (cucumis sativum)

In present era of organic farming, biocontrol agents can be further improved to obtain greater levels of disease reduction. Development of formulations with increased shelf life and broad spectrum action with consistent performance under field conditions could pave the way for commercialization of the technology at a faster rate. In present investigation plant growth promoting rhizobacterial (PGPR) consortium containing three biocontrol bacterial strains (Providencia vermicola AAU PR1 (NCBI ACCN: KJ161325), Pseudomonas putida AAU PR2 (NCBI ACCN: KJ161326) and Pseudomonas fluorescens AAU PR3 (NCBI ACCN: KJ161327) fortified with extracts of botanicals viz. Azadirachta indica (neem), Ipomoea carnea (besharam) and Brassica juncea (mustard cake) was prepared and found to effectively control M. incognita under laboratory conditions and displayed highest reduction in egg hatching after 24, 48 and 72 h of exposure. Seed coating + soil drenching of fortified PGPR consortium was found to enhance plant growth parameters and reduce root knot nematode infestation in cucumber in pot experiment as well as field. Opinion of farmers growing cucumber in protected cultivation (polyhouse / greenhouse) indicated that application of fortified PGPR consortium reduced nematode infestation and replaced chemical measures of nematode control and showed increase in yield providing dual benefit of reducing cost of cultivation with higher yield. All the experimental results signified the efficiency of fortified PGPR consortium for control of root knot nematode disease in cucumber.

Automated summary

The study demonstrates that a consortium of biocontrol bacterial strains and botanical extracts can effectively control root knot nematode in cucumber, leading to a significant increase in yield and reduction in pesticide use.