Effects of different biochar applications on chilli stem rot disease incidence (Sclerotium rolfsii)

Abstract

Chili (Capsicum annuum) is a major, nutritionally rich, important, and commercial condiment crop. MI2 is known for its high pungency and demand in Sri Lanka. Recently chili plants have been affected by Sclerotium rolfsii. Therefore, this research aims to evaluate the effectiveness of different biochar applications on chilli stem rot disease by developing a low cost and environmentally sound disease- controlling method and improving the usage of biochar as disease controlling practice. The experiment was laid out in Randomized Complete Block Design (RCBD) with 3 replicates with seven treatments. The selected variety was MI2 and 40 plants were sown at the rate of two seedlings per hole. Paddy husk, mango sawdust, and coconut shell base biochar were used as treatments at two different application rates (1kgm-2 and 2kgm-2). Biochar was mixed with the soil as an amendment. The sick plot method was used to inoculate the pathogen. It is a common method to assess the health and performance of plant to unfavorable conditions. Disease incidence, plant height and pod yield were recorded. Results revealed that, least number of disease (5.83±3.82) % in T2 (2Kg/m2 paddy husk biochar) while the (40.00±6.61)% in T5 (coconut shells bio char 1Kg/m 2). The number of pods yield (70.00±1.00) and plant height (54.56±1.125) cm were also significantly higher T2(paddy husk biochar 2 Kg/m2) treated plants. The lowest number of pods yield (52.66±1.52) and plant height (44.65±3.58) cm was in T5 (coconut shell biochar 1Kg/m2) except the control. Therefore, this study, 2 Kg/m2 paddy husk biochar is good for reducing chilli stem rot disease incidence. As future works, it is better to conduct field trials using sawdust of other species such as palu (Manilkara hexandra) and jackfruit (Artocarpus heterophyllus) to improve the effectiveness of biochar application.