The effectiveness of some pesticides in the control of thrips and red spider mites on strawberry plants

Abstract

This study was carried out in a private farm in Wardan, Giza governorate in Egypt during 2019 season on strawberry plants. The first experiment aimed to evaluate the effectiveness of different commercial products in cultivated land including Solo 24% SC (Bifenazate), Arbus 12% SC (Chlorfenapyr + Emamectin benzoate) , Concor 24% SC (Spirodiclofen), Excellent 1.9% EC (Emamectin benzoate) , Top9 (Chitosan 0.1%) , Biomectin 5% EC (Abamectin) and Congest 15% CS (Abamectin + Imidacloprid) in reducing the population densities of two spotted spider mite, Tetranychus uriticae Koch. on strawberry plants. According to general mean percentage of reduction in population of T. uriticae, data showed insignificant differences among the seven tested compounds whereas the mortality percentages were 85.94 %, 82.18%, 81.4%, 79.36%, 78.14%, 77.94% and 75.9%, respectively. From these results; it’s clear that Solo compound is the most effective compound and Congest is the lowest one. The other compounds ranged between them in controlling T. uriticae under these experimental conditions. The second experiment evaluated the effectiveness of different formulations in the nursery including Radiant (Spinetoram 12% Sc), Super Rigo (Naphthyl acetic acid – Chitosan), Top9 and Berna Star (Glyceryl stearate 32%) in reducing the population densities of western flower thrips, Frankliniella occidentalis (Pergande) on strawberry plants. According to general mean percentage of reduction in population of F. occidentalis, data showed significant differences among the four compounds. These compounds could be divided into three groups. The first group contained Radiant compound showing high mortality (63.5%). The second group contained Super Rigo and Top9 compounds showing moderate effect (46.44% & 34.3%), respectively. The third group contained Berna Star compound showing least effect (28.36%). From these results; it’s clear that the chemical compound Radiant is the most effective while the natural compound Berna Star is the lowest in controlling F. occidentalis under these experimental conditions.