| dc.description.abstract | Two lab experiments were conducted on radish (Raphanus sativus var. BARI Mula-1)
extractions to analyze quantitative phytochemical compounds in methanolic radish root
extract (MRRE) and screen antifungal activity of methanolic and aqueous radish extracts
against Alternaria alternata and Sclerotium rolfsii in Agricultural Chemistry Laboratory
and Plant Pathology Laboratory, Hajee Mohammad Danesh Science and Technology
University (HSTU) Dinajpur, Bangladesh during September, 2015 – September, 2016.
Methanolic solvent was used following maceration method, where 15.12 g (30.24%)
brown pungent greaseless jelly-like crude phytochemical substance was extracted from
50 g radish root powder dissolved with 200ml methanol. TLC analysis of MRRE showed
at 1:10 ethyl acetate hexane 6 spots recorded as Rf values, where the highest Rf value
was 0.91 cm and the lowest Rf value 0.29 cm. The 6 spots indicated the presence of 6
different compounds representing R1-R6, where their polarities were ranked from most
non-polar compound traveling longest distance to most polar compound travelling
shortest distance as R1 (0.91 cm) < R2 (0.82 cm) < R3 (0.70 cm) < R4 (0.59 cm) < R5
(0.40 cm) < R6 (0.29 cm). From the nature of the TLC, R1 was probably waxy type
hydrocarbon functioning as mimic in phytodefence. In-vitro inhibitory activity of the
radish extracts against A. alternata and S. rolfsii was screened using poisoned food
technique. Three poisoned media viz. methanolic radish root extract media (MRREM,
T1), aqueous radish root extract media (ARREM, T2) and aqueous radish leaf extract
media (ARLEM, T3), and non-poisoned control PDA media (Tc) were used as treatments.
There were highly significance differences among the poisoned media in reduction of
mycelial growth of the test fungi over non-poisoned control PDA media. MRREM
inhibited the growth of A. alternata and S. rolfsii 94 % and 58.1 %, followed by
ARREM 93 % and 40 % and by ARLEM 90 % and 20 %, respectively, over the control.
It may be concluded that the radish extracts can be used as safe natural botanical
fungicides to control A. alternata and S. rolfsii and methanolic radish root extracts have
more intense antifungal activity than aqueous radish root and leaf extracts. | en_US |
