PHYTOCHEMICAL MANAGEMENT OF COLLAR ROT OF CHILI WITH LEAF BIOMASS OF EUCALYPTUS CAMALDULENSIS

Abstract

Sclerotium rolfsii Sacc. is a devastating soil-borne fungal pathogen that causes collar rot disease in chili (Capsicum annuum L.) and causes pronounced yield losses. In the present study, S. rolfsii inoculated soil was amended with 1, 2, 3 and 4% (w/w) dry leaves of Eucalyptus camaldulensis and their effect was studied on disease incidence, mortality, growth and physiology of the host plant. In positive control, there was 73% disease incidence that was further enhanced to 93% in 1% soil amendment treatment.  However, further increase in dose of soil amendment (2% and 3%) decreased disease incidence to 66% and 53%, respectively. A similar effect of soil amendment was observed on plant mortality. A 3% dose of E. camaldulensis leaf biomass alleviated biotic stress of S. rolfsii and increased leaf dry biomass of chili by 67% as compared to positive control. Chlorophyll content and polyphenol oxidase activity were significantly lower in E. camaldulensis amended treatments over positive control. Protein content was gradually increased by increasing leaf amendment dose while reverse was recorded in case of peroxidase activity. The present study concludes that soil amendment with 3% leaf dry biomass of E. camaldulensis can alleviate biotic stress of S. rolfsii on growth of chili to some extent