Management of charcoal rot of mungbean by two trichoderma species and dry biomass of Coronopus didymus

Abstract

A pot experiment was carried out to check the effect of Coronopus didymus (L.) Sm. dry biomass application (1%, 2% and 3% w/w) and two species of Trichoderma (T. viride and T. aureoviride) on growth and physiology of mungbean [Vigna radiata (L.) WIlczek] under biotic stress of Macrophomina phaseolina (Tassi) Goid. Inoculation of M. phaseolina (positive control) reduced plant survival, shoot and root length as well as plant dry biomass by 22%, 52%, 61% and 64%, respectively, over the negative control (without any amendment). There was 100% plant survival in treatments with T. aureoviride alone or in combination with 1% and 2% C. didymus biomass. Likewise, T. viride in combination with 2% biomass also showed 100% plant survival. Application of 3% C. didymus biomass had a pronounced effect on crop growth resulting in 101%, 233% and 342% increase in shoot length, root length and plant biomass, respectively, over the positive control. Sole inoculation of either of the two Trichoderma spp. significantly enhanced various plant growth parameters over the positive control. In general, in combination with 2% biomass of C. didymus, both Trichoderma spp. proved to be the best choice for improving mungbean biomass under stress of M. phaseolina. Activity of denfense related enzymes viz. peroxidase (PO), polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL) was generally higher in treatments in which 1% C. didymus biomass was applied either alone or combined with Trichoderma spp. in M. phaseolina inoculated soil.