Problemas abióticos em soja nas safras 2019/2020 e 2020/2021 no Norte de Mato Grosso

Abstract

Plant diseases can cause a reduction in production, but for a disease to occur, three requirements must be met: adequate environment for the pathogen's development, presence of the virulent pathogen in the area and susceptible host. In the 2019/2020 and 2020/2021 soybean crops, samples of soybeans with symptoms such as: early plant senescence, grains rotting in healthy pods, white mycelial growth in pods, grains germinating in the field. In addition to these symptoms, the plants had a root system with symptoms of soil compaction. Since in these years there was a water deficit in September and October, a period in which the sowing and emergence of the soybean crop is taking place, this work aims to relate the presence of phytopathogens found in the samples with the climatic data and characteristics of the samples received, with in order to understand what occurred. Macrophomina sp. was found in 61.40% of samples received from the 2019/2020 and 2020/2021 harvests, being considered a bioindicator of abiotic problems. Therefore, compaction is restricting the root development of the soybean crop, which consequently reduces the absorption of water and nutrients under ideal growing conditions, thus limiting the source and drain relationship, resulting in symptoms of abortion in the pods and increasing the occurrence of disease, mainly Macrophomina sp.