Distribuição espaço-temporal da Bemisia tabaci (Gennadius,1889) biótipo b na soja na microrregião de Paragominas - Pa.

Abstract

Soy is a crop of great importance on the world and national scene, responsible for a large part of animal and human food, in addition to having great potential for the manufacture of fuel such as biodiesel. However, there are several factors that interfere negatively for a good production of this vegetable, among them the damage caused by insects, where one of the main ones is the whitefly. This work aimed to evaluate and observe the whitefly infestation and the spatiotemporal distribution of the insect in its developmental stages (egg, nymph and adult). The experiment was evaluated in three consecutive harvests, 2015, 2016 and 2017. The experimental design was in randomized blocks in the split plot scheme (20 plots x 11 evaluations x 4 blocks), corresponding to the evaluation of the infestation of 20 soybean cultivars and 11 sampling dates at 07, 14, 21, 28, 35, 42, 49, 56, 63, 70 and 77 days after emergence (DAE) and the insect distribution in the area was evaluated according to the number of infestations and the climatic variables. For data analysis, variance (ANOVA) was performed using the F test (Fisher), and the means, when they differed significantly from each other, compared by the Tukey test at 5% probability. And for the geostatistics analysis, the SUFFER 7.0 program was used. The development stage in 2015 that shows a greater preference for the whitefly was 56 days after emergence. In the year 2016, at 14 and 21 days after the emergence of the plants, they were the most favorable periods for the development of B. tabaci biotype B. In general, in the 2017 harvest, the largest populations in the insect's development stages were found at 07, 14, 21 and 28 DAE. The B. tabaci infestation showed that there were only significant results in the (positive) correlation in the year 2016 evaluating the infestation of whitefly nymphs with rainfall, egg infestation with rainfall and egg infestation with minimum temperature. The spatial distribution occurred, predominantly, in clusters with spatial dependence described by the exponential and spherical models. These results showed that the development stage of the plant and B. tabaci interferes in the population and its infestation in soybeans.