Fine scale analysis of the spatial structure of an Argentinian population of Anastrepha fraterculus using molecular (SSR) and morphometric markers

VILARDI, J.C.; FREILIJ, D.; FERREYRA, L.I.; GÓMEZ CENDRA, P.V.

BOGOTÁ

Congreso; Congreso Americano de Moscas de la Fruta ? 10 Reunión TWWH; 2020

Grupo de Trabajo en Moscas de la Fruta del Hemisferio Occidental - Tephritids Workers of Western Hemisphere (TWWH)

An efficient integrated management program may be improved using information of geneticstructure, population dynamics, and adaptive landscape of the target species. In the present studyphenotypic, genotypic and environmental data were combined, within the frame of a landscapegenetics analysis, to uncover the spatial population genetic structure (SGS) of an Anastrephafraterculus population. Eight SSR loci and six morphometric traits were analyzed in 105 adultsemerged from 35 fruits of 7 guava trees. The sampling site is located at San Pablo, Tucumán,Argentina, where guava trees grow without any horticulturalcare. The orchard is mostly linear anddistance between neighbor trees would be shorter than the dispersal capacity of adult flies. Thedistribution of molecular and morphometric variances was evaluated respectively by AMOVA andmultivariate generalized linear analysis, considering the hierarchical levels: tree / fruit / individual.Genetic variability and population structure were analyzed with the package hierfstatof R. Spatialautocorrelation (SA) of molecular and morphometric data was analyzed at global and local scalewith the package EcoGenetics. Finally, geographic, molecular and morphometric information wascombined in an integrative landscape analysis conducted with the package Geneland. The locianalyzed were very variable an average of 12 alleles per locus and HE= 0.72. Homozygote excesswas observed in the whole population (FIS= 0.11) and genetic differentiation among fruits was low(FST= 0.024). The eight SSR loci allow to identify each sampled individual by its multilocusgenotype. The highestproportion of molecular variance occurred within individuals, followed bythe variance among individuals within fruits. The variation between trees, although small, wassignificant. For morphological traits the highest proportion of morphometric variance was found atthe tree level, and the lowest among individuals within fruit. SA analysis failed to show anysignificant association between neither genetic nor morphometric differentiation with geographicaldistance. Geneland analysis identified 3 clusters with a low level of admixture. One cluster involvesall individuals emerged from the trees in the middle of the sampling site. The other two clusterscorrespond to individuals retrieved from trees at opposite edges of the sampled area. Taken as awhole theanalyses conducted showed significant differentiation among flies emerged fromdifferent trees. There is a cryptic structure revealed by the identification of at least 3 clustersspatially separated. Most individuals obtained from fruits of the same tree belong to the samecluster. This might be related to local environmental conditions affecting female choice ofegglaying site.