Efficacy of Salicylic Acid, Aqueous and Dichloromethane Fractions of Azadirachta indica Seed Extract against Mycelial Growth of Sarocladium oryzae
Abdu K, Wada Y. Ibrahim, Sani, L. A, Babura, S R, Musa, A, Muhammad A N, Isah S. D and Galadima M
Keywords: Efficacy, Azadirachta indica, Sarocladium oryzae, Salicylic acid, Dichlomethane, Aqueous
Abstract
Food security is the number one key factor for sustainable development. Food products from plants are facing biological threat especially by plant pathogens: Fungi, Bacteria, Virus and Nematodes. The aim of this study was to evaluate the effect of salicylic acid and fractions of Neem seed extracts against mycelial growth of Sarocladium oryzae (rice sheath rot disease causal agent) under in-vitro condition. The research was carried out in Plant Pathology Laboratory of Plant Biology Department, Bayero University, Kano. Seeds of A. indica were collected, oven dried, grinded, extracted and fractionated using methanol, ethanol, dichloromethane and aqueous solvent system. S. oryzae was isolated from naturally diseased rice plant growing areas. Dichloromethane and aqueous fractions of A. indica extract 2%, 6% and 10% as well as 5mM, 10mM, and 15mM concentrations of salicylic acid were prepared from stock solution of 100% in g/ml and moles concentrations respectively. Five milliliter (5) of the prepared fractions that is 2%, 6%, 10% concentrations of A. indica and 5mM, 10mM, and 15mM of salicylic acid were separately incorporated in the media containing potato dextrose agar as food poison technique. The plates were inoculated with 10mm disc of S. oryzae mycelial mat. Mycelial growth and zone of inhibition were recorded in percentage. The data obtained were subjected to Analysis of Variance (ANOVA) at 5% level of probability. Results were tabulated, ranked and interpreted. Findings revealed that, 10% dichloromethane fraction produced the lowest mycelial growth of S. oryzae (8.00mm), while widest mycelial growth was recorded on the media supplemented with distilled water (39.33mm). Similarly, zone of inhibition was greatest on the media fortified with 10% dichloromethane (80.30%). All other treatments inhibited mycelial growth of S. oryzae.