Combination of biopesticide formulations to manage Meloidogyne incognita and Fusarium oxysporum f. sp. cepae disease complex in onion

Biopesticide formulations of Bacillus pumilus (BPS4) and Pseudomonas monteilii (PMS2) were tested in combination with Trichoderma harzianum (IIHR-TH2) against Meloidogyne incognita (Kofoid and White) Chitwood and Fusarium oxysporum f. sp.cepae Schlecht (FOC) infecting onion under nursery and field conditions. Seed and soil treatment with biopesticides was done for nursery experiment at 20 g kg⁻¹ seeds and 6 g kg⁻¹ coco-peat, respectively. For field trials, biopesticide enriched vermicompost was applied to the beds at 50g m⁻². Application of biopesticides significantly reduced the disease incidence in nursery experiment. Combination treatments of biopesticides were more effective and reduced the nematode infestation (47.6% to 71.4%) as well as disease incidence of FOC (63.5% to 72.0%), in the field experiment. There was a significant increase in the yield (26.1% to 28.8%) of the crop over control. Thus, the results outline the potential of combination treatments of B. pumilus, P. monteilii and T. harzianum in the production of healthy onion seedlings under nursery conditions whereas increased yield and the management of M. incognita and FOC complex under field conditions.