Article info.

ABSTRACT

Received 31 May 2018
Revised 03 Aug 2018

Accepted 30 Nov 2018

This report was aimed to evaluate the effectiveness of treatments for lesser coconut weevil (Diocalandra frumenti) with green muscardine fungus (Metarhizium anisopliae) and some insecticides at the laboratory and farmer’s coconut orchards. Results showed that the isolates of M. anisopliae at the concentration of 10⁸ spores.mL^-1 killed D. frumenti adults under laboratory condition (T = 28-31⁰C; RH = 60-70%). In the laboratory, the corrected effectiveness of Ma5, Ma2 and Ma1 were 100%, 95.0% and 95.8% at day 15 after treating. Both Emamectin benzoate and Fipronil gave effective control of the beetles at 100% after 3 days of treating. Among four tested concentrations, the 10⁹spores.mL^-1gave higher effectiveness up to 96.7% after 15 days of treating. In the farmer’s coconut orchard, the results also showed coconut fruits damaged by the weevil clearly reduced from 35 days after treating. At 65^th day, all of treatments applied with M. anisopliae gave effective control just at 4.00% and 5.60% (ratios of infected fruits). Meanwhile, insecticide applied with treatments had a higher ratio of coconut fruits infected by this weevil (14.7% and 11.4%).

Keywords

Coconut weevil, Diocalandra frumenti, insectisides, in the field, laboratory, Metarhizium anisopliae

Cited as: Ung, N.H., Hanh, D.K., Xuan, T.T., Vang, L.V. and Hai, T.V., 2018. Effectiveness of green muscardine fungus Metarhizium anisopliae and some insecticides on lesser coconut weevil Diocalandra frumenti Fabricius (Coleoptera: Curculionidae). Can Tho University Journal of Science. 54(8): 1-7.