Compatibility of Pasteuria penetrans with fungal parasite Paecilomyces lilacinus against root knot nematode on Chilli (Capsicum annuum L.)

Abstract

Chilli (Capsicum annuum L.) crop is highly susceptible for the root knot nematode Meloidogyne incognita and every year this nematode causes great loss to the crop. The present study investigated the cumulative effect of two biocontrol agents viz. Pasteuria penetrans and Paecilomyces lilacinus against M. incognita. Two doses of P. penetrans i.e. 50g/Kg and 100g/Kg infested soil were applied either alone or in combination with two doses of P. lilacinus i.e. 4g spore culture/Kg and 6g spore culture/Kg of soil. Application of P. penetrans with P. lilacinus resulted into relatively better improvement in various growth attributes of chilli when compared with the individual application. Amongst the various treatments tested combined application with the higher dose of both bioagents (i.e. 100g P. penetrans infested soil with 6g of P. lilacinus/Kg) showed maximum improvement in fresh and dry weight of shoot and root over the nematode check and it was almost at par with that of the absolute check. The combined application of both the bioagents at higher dose resulted in 139 and 84% increase in dry weight of shoot and root over the nematode check respectively. The combined application of both the bioagents was also observed to cause higher reduction in gall number and nematode population than their individual application except for the treatment having lower dose of the P. penetrans with P. lilacinus where reduction in both the parameters was observed to be at par with that of the either dose of P. penetrans or higher dose of P. lilacinus. Combined application with higher dose of P. penetrans and P. lilacinus showed maximum reduction of 62.6 and 82.2% in gall numbers and nematode population over the nematode check.