Resistência de Cultivares de Soja a Mosca-Branca Bemisia tabaci (Genn., 1889) (Hemiptera: Aleyrodidae), em Condições de Campo, no Polo Paragominas de Grãos.

Abstract

Soybeans are the fourth largest cereal product in the world with high production and marketing rates. The whitefly biotype B is a sucking insect belonging to the Hemiptera Order, this pest is capable of feeding more than 600 species of plants, consequently causing economic damages. The objective of this study was to evaluate the resistance of soybean cultivars to whitefly under field conditions in the Paragominas grains pole. Two experiments were carried out (in the years 2015 and 2016), with a randomized block design (DBC) in subdivided parcels, delimiting an area of 25x40m distributed in 4 blocks with 20 soybean cultivars, each parcel 2x5m, containing four lines of soybean planting at a spacing of 50 cm, the B. tabaci B biotype incidence samplings were started at 07 days after plant emergence (DAE), and the number of eggs, nymphs and adults was recorded weekly. In the year of 2015 the infestations of the pest obtained differences for all the stages of development of B. tabaci, egg, nymph and adults; with regard to the experiment of the year 2016, high infestations of whitefly were observed in the 20 soybean cultivars, however, there was no difference between eggs, nymphs and adults. In relation to the year 2015, the cultivars SYN1183, P99R03, P98C81 and Uruçuí presented higher preference indices for oviposition, differing from cultivar P98Y51, which showed the lowest mean of infestation (13.99), already in the experiment of the year 2016 to 14 and 21 days after the emergency (DAE), were the most favorable periods for the development of B. tabaci biotype B.