Monitoring and control strategies for mealybug of persimmon in Australia

Abstract

Mealybug is the most important pest of persimmon in temperate environments and one of the three most important pests in subtropical growing areas of Australia. The species of concern to the sweet persimmon industry are citrus mealybug (Planococcus citri), longtail mealybug (Pseudococcus longispinus) and citrophilous mealybug (Pseudococcus calceolarieae). The dominant pest species in subtropical environments (e.g., Queensland) is citrus mealybug, whereas longtailed and citrophilous mealybug predominate in the temperate growing regions across southern Australia. Little is known of the population dynamics of these mealybug pest species, particularly in relation to crop phenology. Knowledge of the timing of mealybug infestation and particularly the presence of the susceptible juvenile stages, is a key factor in the effective control of mealybug. Several methods for monitoring mealybug population dynamics were investigated, including pheromone traps, sticky bands and the visual inspection of roots. Field trials conducted to establish the efficacy of preharvest chemical treatments in controlling mealybug. The objective was to replace broad-spectrum insecticides with chemistry compatible with the use of predators and an IPM strategy. Field trials included clothianidin, spirotetramat, sulfoxaflor, thiamthoxam, and imidacloprid, as well as the timing of applications of clothianidin. The effectiveness of monitoring techniques and preharvest insecticide treatments will be discussed.