EFFICACY OF PUCUK IDAT, KEMUNTING, AND KEDEBIK LEAF POWDERS AGAINST SitophiluS oryzaeL. ON PADDY AND FIELD RICE

Abstract

This study addresses the significant challenge of rice weevil (Sitophilus oryzae L.) infestation, which can cause yield losses of up to 70% in stored rice. This study aimed to assess the sustainability and environmental friendliness of botanical pesticides. The botanical pesticides used were wild shrubby vegetation such as pucuk idat (Cratoxylum glaucum), kemunting (Rhodomyrtus tomentosa), and kedebik (Melastoma malabathricum). These plants were selected for their natural resistance to pests, suggesting the presence of bioactive secondary metabolites. Using a factorial completely randomised design, this study examined the effect of plant species, rice types (paddy and field rice), and four doses of botanical pesticides (10, 15, 20, and 50 g) on ​​rice weevil mortality. The results showed that the three types of botanical pesticides were significantly effective in controlling S. oryzae. The highest mortality rate of 83.3% was observed in the rice treatment with 20 g of pucuk idat leaf botanical pesticide. Mortality began to appear on the third day after treatment and peaked around the sixth day. This pattern indicates a delayed but potent toxic effect, likely due to bioactive compounds or secondary metabolites present in the plant leaves. Furthermore, interactions among plant species, rice varieties, and dosage strongly influenced the efficacy of this botanical pesticide. This research provides a foundation for the use of botanical pesticides as an effective, sustainable, and environmentally friendly alternative to rice weevil infestation. The application of botanical pesticides can support food security and sustainable agriculture by utilising the value of local plant biodiversity.