DNA barcode for the identification of the sand fly Lutzomyia longipalpis plant feeding preferences in a tropical urban environment

Abstract

Little is known about the feeding behavior of hematophagous insects that require plant sugar to complete their life cycles. We studied plant feeding of Lutzomyia longipalpis sand flies, known vectors of Leishmania infantum/chagasi parasites, in a Brazilian city endemic with visceral leishmaniasis. The DNA barcode technique was applied to identify plant food source of wild-caught L. longipalpis using specific primers for a locus from the chloroplast genome, ribulose diphosphate carboxylase. DNA from all trees or shrubs within a 100-meter radius from the trap were collected to build a barcode reference library. While plants from the Anacardiaceae and Meliaceae families were the most abundant at the sampling site (25.4% and 12.7% of the local plant population, respectively), DNA from these plant families was found in few flies; in contrast, despite its low abundance (2.9%), DNA from the Fabaceae family was detected in 94.7% of the sand flies. The proportion of sand flies testing positive for DNA from a given plant family was not significantly associated with abundance, distance from the trap, or average crown expansion of plants from that family. The data suggest that there may indeed be a feeding preference of L. longipalpis for plants in the Fabaceae family.

Plant-feeding phlebotomine sand flies, vectors of leishmaniasis, prefer Cannabis sativa

“…Findings largely concurred with previous studies, demonstrating a preference of Lu. longipalpis for cultivated gardens over the endemic vegetation (9,14). Interestingly, circumstantial evidence Feeding percentages of males and females were not significantly different (χ 2 = 2.2857, df = 1, P = 0.1306).…”

“…The attraction of sand flies to specific plants was documented in several field studies (9,14,26). Since our findings resulted from surveys rather than experiments, we could not assess the relative attraction of sand flies to common plants.…”

“…The specific types of sugars and their relative concentrations in honeydew can be used to incriminate honeydew consumers (7)(8)(9), while the plant sources of phloem-feeding insects can be identified by plant-specific PCR followed by DNA sequencing (12). The utility of PCR-based approaches for identifying plants consumed by phlebotomine sand flies has been demonstrated in several studies (13,14). Most of these studies employed the ribulose bisphosphate carboxylase large chain (rbcL) gene, which is an accepted marker for phylogenetic and barcoding studies of plants (15).…”

Entomological signatures in honey: an environmental DNA metabarcoding approach can disclose information on plant-sucking insects in agricultural and forest landscapes

“…Studies in other biological systems, from insects to mammals, have used DNA metabarcoding approaches to identify the species composition of the diet of different animals (e.g 38 – 43 . ), with a direct identification on the DNA recovered from gut content or feces.…”

Transmission blocking sugar baits for the control of Leishmania development inside sand flies using environmentally friendly beta-glycosides and their aglycones

“…The absence of trehalase modulation also suggests that sand flies might not be well adapted to feed on toxic glycosides and this consistent with the fact that toxic glycosides are usually not the most important components of insect diets [ 27 ]. However, recent studies in field populations of L. longipalpis from Teresina, Brazil [ 51 ], showed a dietary preference for plants of the families Fabaceae and Rutaceae, in which several secondary metabolites are present, such as coumarins. Thus, more studies are needed to identify which plant components are present in the diet of wild sand flies.…”