BIOCHEMICAL INVESTIGATION OF RADISH ROOT TOWARDS THE DEVELOPMENT OF BOTANICAL FUNGICIDE AGAINST Alternaria

Abstract

The root of Tasaki Sun Mula (Bari Mula-1) was used to determine the antifungal biochemical substances and the effectiveness of its aqueous extract on the growth of Alternaria brassicae. Different solvents like polar nature viz. water, methanol, ethanol and as well as non-polar nature viz. Petroleum ether, Chloroform were used for extraction. Among the solvents, methanol extract contained the highest amount of crude products (15.2g) whereas ethanol extract (9.95g), water extract (8.94g), chloroform extract (0.91g) and petroleum ether extract contained (0.63g). During TLC, ethanol crude extract produced four distinct spots at hexane and ethyl acetate (20:1; v/v). The different compounds detected by TLC were designated as R;- Rg where R;, is the most non-polar and Rg is the most polar compound where the polarity of different compounds may be arranged as R;<R2<R3<R4<R5<Rg, The TLC of aqueous extracts were not possible due to solubility. From the nature of TLC it is very clear that R; is probably waxy type hydrocarbon functioning as mimic in plant defense. In the study of aqueous extract, three different types of media viz. PDA, Radish Leaf Extract Media (RLEM) and Radish Root Extract Media (RREM) were prepared for observing the growth of Alternaria brassicae. Up to seven days, the mycelia growth on both selective media were same (7 cm) but after seven days mycelial growth was continued on RLEM and turned into blackish color whereas mycelia growth was stunted on RREM and remained whitish color. Abundant numbers of conidia were found in RLEM but no conidium was found in RREM. There was no growth in PDA media. Finally it might be concluded that Radish root may contain six different biochemical compounds functioning as anti pathogenic to Alternaria brassicae.