A sequential binomial sampling plan for potato psyllid (Hemiptera: Triozidae) on bell pepper (Capsicum annum )

Abstract

Potato psyllids (Bactericera cockerelli Sulc) are a pest on solanaceous crop plants, including bell peppers. Potato psyllids vector Candidatus Liberibacter psyllaurous, but bell peppers (Capsicum annum L.) do not exhibit symptoms from infection. Potato psyllids show variation in spatial patterns and host choice with cultivar and plant species. Consequently, a study of spatial distribution and sampling plan specific to bell peppers is necessary for management of this insect pest, as those developed for other crops are unlikely to transfer among crops. Potato psyllids were evenly distributed on both sides of leaves but prefer the top two-thirds of pepper plants. Within fields, psyllids demonstrated an aggregated spatial distribution, but the edge effect observed in other crop plants was absent. Eggs and nymphs had similar spatial distributions that differed from adults. A series of nymph-based sampling plans were examined. Sampling plans based on an infestation of less than 41% of plants infested (5 nymphs plant(-1)) were statistically unacceptable, while little difference was found between the 41% infestation plan and 56% (20 nymphs plant(-1)) infestation plan. At 41%, an average of 11 and maximum of 49 samples would be necessary to make a treatment decision. The binomial sequential sampling plan presented here offers an important yet simple tool for managing potato psyllids in bell pepper.