Morphometric variation and fluctuating asymmetry in populations of Closterocerus coffeellae (Ihering) (Hymenoptera: Eulophidae) in different management and landscape of coffee agroecosystems

Abstract

Closterocerus coffeellae (Hymenoptera: Eulophidae) is a parasitoid of the coffee leaf miner occurring in coffee farms with high selection pressure caused by pesticides and different landscape patterns on the surrounding crops. This work aims to detect morphometric variations and levels of Fluctuating Asymmetry (FA) in the wings of C. coffeellae in coffee farms with a history of insecticide use and different landscape composition in the Planalto region, Bahia, Brazil. Parasitoids originated from six coffee farms in this region. We prepared microscopy slides of the right wings of 30 C. coffeellae females from each population. We determined variations in wing size and shape by geometric morphometry analysis, adding 1 landmark and 9 semi-anatomical landmarks to the wings. The landscape metrics (3 km radius) and levels of spatial dependence for size and AF were calculated using geostatistical analysis. Higher forest cover and edge density in coffee plantations lead to an increase in the wing size of C. coffeellae and reduced wing FA levels. Diversity of the surrounding agricultural land cover in coffee farms and pesticide use reduces wing size and increases levels of FA in coffee farms. The centroid size exhibited strong and moderate aggregation levels across coffee farms. The conservation of C. coffeellae is recommended since the species can be used as a bioproduct against the coffee leaf miner, and as a biocontrol solution for coffee farms. Furthermore, adopting conservative practices of natural vegetation surrounding coffee farms is essential for the parasitoids. It must be included in the coffee leaf miner management, mainly in farms with higher agricultural cropland diversity on surrounding coffee farms and with higher pesticide use.