Spatial distribution of soybean plants infested with whitefly Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae)

Renato Suekane,Paulo Eduardo Degrande,Thiago Moreira Azambuja,Carlos Tutida Menegati,Elmo Pontes De Melo

doi:10.1590/1808-1657000642016

Renato Suekane, Paulo Eduardo Degrande + Show 3 more

Open Access

https://doi.org/10.1590/1808-1657000642016

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Abstract

ABSTRACT: The determination of the spatial distribution of a pest is the first step in the establishment of a sampling plan, as sampling methods are contingent upon the type of spatial distribution of the specific pest studied, varying according to the number and size of samples in the area. This work aimed to study the spatial distribution of soybean plants infested with Bemisia tabaci, under field conditions, through the determination of the aggregation indices and the chi-square test of fitness to the main types of theoretical frequency distributions. The average percentage of whitefly (B. tabaci) infestation increasing after the V1 stage, reaching the maximum infestation of 60.3% in the R1 stage. At the R2 stage, the percentage of infestation ranged from 20 to 40%. According to the models of theoretical distributions studied, the Poisson distribution best defines the distribution of the whitefly.

Highlights

MATERIALS AND METHODSThe whitefly Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) causes economic damage to several crops, including soybean Glycine max (L.) Merrill, by extracting a large amount of sap from the phloem and negatively affecting plant growth and development
This insect excretes a large amount of molasses, which is rich in sugar and serves as a substrate for the development of the sooty mold-causing fungus Capnodium spp. (Capnodiaceae), thereby decreasing photosynthesis and in some cases leading to plant death (LOPEZ et al, 2008). This species has the ability to transmit viruses, and in soybeans, B. tabaci is a transmitter of the stem‐necrosis virus (Carlavirus), which can lead to death of the host
B. tabaci has been recognized as a pest for several crops for many years, but its populations used to be small to the point of not causing economic damages

Summary

Introduction

MATERIALS AND METHODSThe whitefly Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) causes economic damage to several crops, including soybean Glycine max (L.) Merrill, by extracting a large amount of sap from the phloem and negatively affecting plant growth and development. This work aimed to study the spatial distribution of plants infested by Bemisia tabaci, in a soybean crop, by determining aggregation indices and the chi-square test of fitness to the main types of theoretical frequency distributions.

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