Whiteflies are among the most important agricultural insect pests worldwide, causing severe damage and yield losses to numerous crops. On vegetables, Bemisia tabaci and Trialeurodes vaporariorum are largely the key whitefly pests. All over the World, they feed on more than 700 host plant species, transmitting more than 100 types of virus diseases. Their attacks are widely diffused on many vegetable crops in Mediterranean areas, including Sicily, where B. tabaci transmits virus diseases such as TYLC and ToC and T. vaporariorum transmits TIC and ToC. Due to its economic importance, several field surveys on B. tabaci were conducted in Sicily during the past years, to determine the biotypes distribution in cultivated areas, but poor information is available on populations of this whitefly occurring in natural environments, and almost nothing is known for T. vaporariorum. To fill this gap, a survey is being conducted in Sicily, to determine the distribution of these two species (and their eventual biotypes) in both natural and cultivated areas and analyze comparatively their parasitic complex in different ecological context. Collecting sites are selected in different environments: natural parks, protected areas, organic and conventional farms (both protected and open field vegetable crops), gardens. Data points are taken using GIS techniques, in order to make a precise estimates of distribution areas of species and biotypes as well as collect a set of comparative data allowing a future study on dynamics of whitefly populations. The field work is spread out in several quadrants, as to cover the whole investigated area in a spatially balanced manner as possible. In the present contribution, results are given in relation to the biotypes status and distribution in Sicily of B. tabaci, evaluated by micro-satellite analysis and enzymatic digestion of the cytochrome oxidase I (COI) gene, as well as the distribution of T. vaporariorum, analyzed by the second technique. Preliminary evaluation is also attempted on parasitization of both species in different ecological contexts.
|Titolo:||Survey on Whiteflies attacking Vegetable Crops in Sicily: Difference between Natural and Cultivated Environments and Use of GIS Techniques for Data Extrapolation|
|Data di pubblicazione:||2011|
|Appare nelle tipologie:||4.2 Abstract in Atti di convegno|