Damage, make-decision system, control of Pseudophilothrips sp. (Thysanoptera: Phlaeothripidae), and its relationship with fungic lesions on guava fruits - DOI: 10.4025/actasciagron.v25i1.2675

Abstract

This work aimed to study the damage, make-decision system, control of Pseudophilothrips sp. (Thysanoptera: Phlaeothripidae) and its relationship with fungic lesions on guava fruits. The thrips Pseudophilothrips sp (Thysanoptera: Phlaeothripidae) and the fungi Collethotricum gloesporiodes and Pestalotia sp were observed on fruits with lesions. The number of lesions/fruit increased in function of the numbers of nymphs and adults of thrips/fruit. The most effective insecticides were carbaryl, cypermethrin, dichlorvos, ethion, fenpropathrin, fenitrothion, fention, lambdacyhalothrin, metamidofos, methyl parathion, permethrin, triclorfon, and vamidothion. The thrips sampling should be done by evaluation of the percentage of young attacked fruit (1.5 to 3 cm of diameter) by nymphs and adults of thrips. The sampling plan should be composed by evaluation of four fruits/plant on nine plants/field. The average of the economic thresholds for red guava cultivars were 0.70% (tractor insecticide application) and 1.82% (conventional knapsack sprayer) of infested guava fruits. The average of economic thresholds for white guava cultivars were 1.15% (tractor insecticide application) and 2.96% (conventional knapsack sprayer) of fruits with Pseudophilothrips sp.