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Toxicity of Malaysian Medicinal Plant Extracts Against Sitophilus oryzae and Rhyzopertha dominica

Arshia Hematpoor, Sook Yee Liew, Hasmahzaiti Omar, Jamil Ahmad Shilpi, Azeana Zahari, Devi Rosmy Syamsir, Haslinda Mohd Salleh, Norsita Tohar, Rosalind Pei Theng Kim, Ahmad Kaleem Qureshi, Ayu Afiqah Nasrullah, Gomathi Chan, Soon Huat Tiong, Omer Abdalla Ahmed Hamdi, Muhammad Remy Othman, Sow Tein Leong, Khalijah Awang, Masdah Mawi and Norhayu Asib

Pertanika Journal of Science & Technology, Volume 45, Issue 4, November 2022


Keywords: Antifeedant, insecticidal activity, lesser grain borer, Malaysian medicinal plant, rice weevil

Published on: 4 November 2022

The insecticidal activities of extracts from 22 Malaysian medicinal plant extracts from 8 botanical families were tested against rice weevil: Sitophilus oryzae (L.) and lesser grain borer: Rhyzopertha dominica (F.). The extracts were obtained using hexane, methanol, and dichloromethane to extract potential biopesticides from dried leaves. The toxicity levels were examined periodically based on antifeedant activity and contact toxicity assays using treated grain assay. Hexane extracts of Alpinia conchigera, Alpinia scabra, Curcuma mangga, Curcuma purpurascens, Goniothalamus tapisoides, Piper sarmentosum , and methanol extracts of Curcuma aeruginosa, C. mangga , and Mitragyna speciosa were the most potent extracts against S. oryzae and R. dominica with lethal concentration (LC50) values of ≤ 0.42 mg/mL and ≤ 0.49 mg/mL, respectively. The contact toxicity test results showed that methanol extracts of C. aeruginosa and C. mangga , dichloromethane extracts of Cryptocarya nigra , and hexane extracts of C. mangga, and C. purpurascens resulted in 100% mortality of both pests within 28 days exposure of 5 mg/cm2 concentration.

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