Biostimulants and insecticides for biorational management of serrano chili (Capsicum annuum L.) in protected macrotunnel conditions

Abstract

The objective of this study was to evaluate the effect of two biostimulants and two insecticides in the biorational management of serrano chili cultivation under protected macrotunnel conditions. Three biostimulant treatments were evaluated: 1) T22^® (Trichoderma harzianum strain T22), 2) Mix^® (T. harzianum, T. viride, T. asperellum, T. komimgli), and 3) control (water), applied at a dose of 0.5% (w/v). The experimental design was a random complete block factorial. The response variables for the biostimulants were fruit weight, equatorial and polar diameter, and the total weight of 20 fruits. For the insecticides, a single application of each product was made. Aphis sampling was carried out before application and at 3, 5, 7, and 14 days after application (daa). The results demonstrated greater potential for the biostimulant formulate with T. harzianum strain T22 to increase the weight and size of serrano chili fruits, as well as for the spirotetramat-based insecticide to control aphids. The fungus I. javanica 304 was effective at 7 and 14 daa, but with mortality rates lower than 60%. The interactions of biostimulants and insecticides had a beneficial effect on fruit weight and size and pest control.