FPRC Forest Protection Research Centre (FPRC)
N. M., Chi, D. N., Quang, B. D., Hien, P. N., Dzung, N. P., Nhung, N. V., Nam, P. T. T. Thuy. & B. Dell
International Journal of Tropical Insect Science volume 41, pages 2341–2350 (2021)
Abstract: Chukrasia tabularis is a high-value tree in the mahogany family and in Vietnam is grown in home gardens and small plantations. One to 3-year old trees are susceptible to shoot tip damage from larvae of Hypsipyla robusta which feed inside the stem. With the recent expansion of C. tabularis plantations, the forestry sector is seeking management options for this pest. Therefore, the efficacy of a range of commercial insecticides and biological agents were evaluated in nursery and plantation experiments. Twenty days after application of carbaryl, carbosulfan, deltamethrin or fipronil to the shoots of 1-year old nursery seedlings, damage from inoculated H. robusta was reduced by 83–100%. Application of Bacillus thuringiensis, Beauveria bassiana or Metarhizium anisopliae were less effective, reducing damage by 58, 33 and 42%, respectively. In 2-year old trees in the field, damage from natural H. robusta infestation was reduced by >75% at 30 days after application of carbaryl, carbosulfan, deltamethrin or fipronil. Including alkyl sulfonate or trisiloxane ethoxylate as adjuvants into the spray mix reduced damage by up to 98%. Soil applied fipronil granules and foliar-applied B. thuringiensis were less effective treatments (72 and 63%, respectively). The most effective treatments can now be evaluated in more extensive trials so that management protocols can be provided to end-users.