Abstract :
A study was conducted on Anacardium occidentale Linn. (Cashew) from Terengganu and Kelantan states of Malaysia, with the aim to determine the allelopathic effects of leaf and root extracts on the growth of bioassay plant species, Zea mays (maize) and Cucumis sativus (cucumber). On exposure to leaf and root aqueous extracts at 10 g/L, 50 g/L and 100 g/L concentrations, the growth of these bioassay plant species were found affected. With the increasing concentrations of leaf and root aqueous extracts, the percentage of germinations and radicle lengths of bioassay species were reduced. These findings showed that phytochemicals in the tissues of A. occidentale caused insignificant phytotoxic effects on growth of Zea mays and Cucumis sativus seeds. The leaf extract of A. occidentale showed similar phytotoxicity effects as that of its root extract, on the growth parameters of tested species. The different effects between leaf aqueous extracts and root aqueous extracts could be contributed by different allelochemical quantities or entities presence in plant tissues. This experiment showed similar trend of inhibition from both extracts, however some extracts obtained from Terengganu gave more inhibition effect compared to extracts obtained from Kelantan.
