Evidence for coabundance of leafminer flies and whiteflies in melon crops

Leandro José Uchôa Lemos,Roberto Victor Barros,Reginaldo Barros,Tiago Cardoso Da Costa-Lima,Wesley Augusto Conde Godoy

doi:10.1590/1678-4499.20190459

Abstract

ABSTRACT Interspecific competitions are important mechanisms in structuring ecological communities, including agroecosystems, in which different species may share the same food resource. In melons, two major pests coexist in time and space, Liriomyza sativae Blanchard (Diptera: Agromyzidae) and Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). The former feeds on the leaf mesophyll, while the latter on the phloem sap. Therefore, the same niche exploitation can trigger interactive processes between both populations. The present research aimed to determine if there are positive or negative interactions between whiteflies and leafminers under field conditions. The experiment was conducted in four commercial melon fields in northeast Brazil in two planting seasons. Thirty random plants were weekly selected for detection of whitefly nymphs and leafminer larvae throughout the entire crop cycle. The data was organized and analyzed considering the species abundance of L. sativae (larvae) and B. tabaci (nymphs and adults) in the same plant. Thus, the coabundance of species was investigated by using regressions with Poisson errors. The results suggest different fractions of negative, positive and neutral (not significant relationships) coabundance between the two species. Among 34 significant interactions, 56% were negative, suggesting that more than half of significant interactions are due to interspecific competition with negative coabundance.

Highlights

Interspecific interactions between populations of organisms describe relationships capable of regulating patterns of distribution, abundance and species diversity within ecological communities (Kaplan et al 2011)
Two major pests coexist in time and space, Liriomyza sativae Blanchard (Diptera: Agromyzidae) and Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae)
Among 34 significant interactions, 56% were negative, suggesting that more than half of significant interactions are due to interspecific competition with negative coabundance

Summary

Introduction

Interspecific interactions between populations of organisms describe relationships capable of regulating patterns of distribution, abundance and species diversity within ecological communities (Kaplan et al 2011). Co-occurrence patterns have been a central concern in community ecology, to investigate segregation and/or grouping in animal communities (Gotelli 2000) This approach is characterized by analysis of presence–absence matrices with “null model” randomization tests (Gotelli 2000), structure that does not allow considering the abundance of species, an important aspect to evaluate interactive processes in local scale (Brodie et al 2018). The leafminer larvae and whitefly nymphs occur mainly on the basal and medium leaves of the melon’s branch (Chagas et al 2019) Both species coexist by feeding on the melon plants and their damage results in large economic losses in this agroecosystem (Baldin et al 2012; Costa-Lima et al 2019)

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Results

Conclusion