Effective biological control of Lentil (Lens culinaris) Fusarium wilt and plant growth promotion through native Rhizobacteria

Abstract

Fusarium wilt (caused by Fusarium sp.) is the most devastating yield limiting factor of lentil (Lens culinaris). For managing wilt, current study implies multifaceted role of plant growth promoting rhizobacteria (PGPR): for plant growth promotion as well as for disease suppression. To achieve this goal 24 bacterial isolates were assessed in dual culture for their antagonistic potential against Fusarium pathogen. Two PGPR (B1: Rhizobium pusense and B2: Burkholderia contaminans) retained their potential as a potent antagonistic bacterium in dual culture with percent inhibition of 72.57 % and 63.42 % respectively. Their antagonistic potential was further confirmed through scanning electron microscopy (SEM), which showed shrinkage and distortion of mycelium as compared to control. They produced antifungal cell wall degrading enzymes such as protease (Solubilization Index = B1-2.10, B2-3.97), chitinase, and catalase. In-vivo growth promotion and disease reduction potential of the isolates were assessed in pot experiment using Markaz 09 and Mansehra Bold 89 under greenhouse conditions. In Markaz-09, selected isolates significantly enhanced growth of shoot(B1 29.03 %, B2-53.50 %)and root (B1-34.45%, B2-59.25 %).Moreover, bacterial strains significantly reduced disease severity over control (B1-44.44 % and B2-91.67 %). These findings indicate that native PGPR might serve not only as a biocontrol to manage wilt, but can also work as bio fertilizer.