RESPOSTAS DE ARROZ A DIATRAEA SACCHARALIS (FABRICIUS) POR IMAGEAMENTO INFRAVERMELHO TERMAL

Abstract

Diatraea saccharalis Fabricius is one of the main pests of the rice crop and its early detection, that is, before the plants show damage, is essential to avoid yield losses and to define effective and rational control. This work aimed to model the infrared-thermal responses of rice cultivars to simulated levels of damage caused by D. saccharalis, and to model the responses of agronomic variables of two cultivars to infestation levels. Two experiments were conducted in a protected environment, in 2019 and 2021, with the IR40 and BRS Irga 409 cultivars, respectively. The seeds were planted in plastic trays with commercial substrate for vegetables and, after twenty days, three seedlings were transplanted into plastic pots with a capacity of 5 L and infested with first-instar larvae of D. saccharalis, ranging from 0, 2, 4, 6 and 10 larvae/plant, with the plants kept in cages covered with voile fabric. It was noticed that the temperature of the leaf surface is related to the level of infestation and can be used for phytosanitary evaluation. From the leaf temperature or the difference between the ambient temperature, it was possible to detect which cultivar IR40 is susceptible, compared to BRS Irga 409