Management of Sesamia grisescens Walker (Lep.: Noctuidae), a sugar-cane borer in Papua New Guinea.
Sesamia grisescens is a serious pest of sugarcane at Gusap, Papua New Guinea, with annual sugar production losses ranging from 5 to 18%, valued at up to US$8.4 × 106. Basic biological studies and various control techniques studied in the last 6-7 years are reviewed. S. grisescens populations are highly synchronized with 5.5 generations/year. Populations tend to peak in May-June and subsequently decline as a result of dry weather. The control of S. griscens requires integration of several cultural and biological inputs, owing to a sugarcane varietal interaction, the time of planting and the harvesting of heavily infested fields. Inundative releases of the braconid Cotesia flavipes gave up to 70% parasitism and the imported eulophid Pediobius furvus slowly became established in the field. The use of systemic insecticides, such as carbofuran, over several seasons was ineffective in controlling S. grisescens. Pheromones are still being evaluated for population monitoring and may be useful for mating disruption.