POTENTIAL USE OF ANIMAL MANURES IN MANAGING PHYTOPHTHORA WILT OF CHILLI CAUSED BY PHYTOPHTHORA CAPSICI

Abstract

Phytophthora wilt of chilli, caused by Phytophthora capsici, is a major concern for many growers because an effective management method has not been identified yet. In agriculture, animal manures have primarily been focussed on the supply of nutrients to the crops but their use for suppression of soil borne diseases is not well investigated and understood. In this study, we examined the efficacy of five different animal manures (poultry, cattle, goat, pig and sheep) at four levels (1, 5, 10 and 20% volume/volume) added to potting mix for management of Phytophthora wilt of chilli. The preliminary study revealed that the quantity of 5 g per pot (500 mL) of P. capsici-colonised millet-seed inoculum was effective for the development of Phytophthora wilt in chilli seedlings grown in coir-based potting media. The main greenhouse experiments were conducted in randomised complete design with five replications. The results showed that all types of manures were effective in increasing the survival rate of chilli by reducing the incidence of Phytophthora wilt. In the first planting all manures caused at least two-fold increase in plant survival compared to the inoculated control. The chilli plant survival was much higher in the second planting when seedlings were planted after six week of incorporation of manures and seven weeks after inoculation of potting mix. Among manures, the highest plant survival percentage at the final assessment was found in pots amended with 20% v/v poultry manure in both the first (66%) and the second (86%) plantings. For sustainable and effective management of Phytophthora wilt of chilli, this study recommends application of poultry manure to growing media two months before planting of chilli seedlings.