Control of Postharvest Decay on Cashew Fruit (<i>Anacardium Occidentale</i> L.) with Aqueous Extract of Cashew Leaf

The study investigated control of postharvest decay on cashew fruit (Anacardium occidentale L.) with aqueous leaf extract of cashew. Freshly emergent cashew leaves were air-dried for 5 days and then pulverized. Varying concentrations (0.5%, 1%, 1.5%, 2% and 2.5%) of the pulverized cashew leaves were prepared with appropriate volumes of water. Fifteen cashew fruits were dipped separately into each concentration of the prepared extract for 1 minute while untreated cashew fruits served as control. Both the treated and control fruits were stored in dessicators at 28±2°C and 45-50% relative humidity and assessed daily for disease incidence. Phytochemical screening of the extract was also carried out. Results obtained on day 1 of storage indicated that both the control and all treated cashew fruits irrespective of treating concentrations had no disease incidence (0%) which implied that all the cashew fruits were disease free. However, as storage duration progressed, there was a decline in the efficacy of the cashew leaf extract. Only fruits treated with 2% cashew leaf extract maintained 0% disease incidence on day 4 of storage and recorded 30% disease incidence on day 7 of storage when compared with control and other treated fruits that had 100% disease incidence. The antifungal activity of the leaf extract could be traced to different phytochemicals present in it.