Fourth International Bemisia Workshop International Whitefly Genomics Workshop
Influence of Weeds on the Whitefly-Virus-Parasitoid Complex in Veracruz, Mexico
1 Programa en Entomología, Campus Montecillo, Colegio de Postgraduados, Montecillo Estado de México. Correspondence: ladeorar@colpos.mx
2 Programa en Agroecosistemas Tropicales, Campus Veracruz, Colegio de Postgraduados, Veracruz, México
The influence of the planned presence of weeds on the whitefly Bemisia tabaci-virus-parasitoids complex in the central coastal region of Veracruz, Mexico was studied. A randomized block design with three treatments and four repetitions was used. The treatments evaluated were: a) tomato with weeds around the edge, b) tomato with free growth of weeds; and c) tomato without weeds. The population density of B. tabaci adults and nymphs per leaflet, the viral incidence, the percentage parasitism and the crop yield, was recorded weekly. Weeds host for B. tabaci were identified and the average parasitism of the pest was determined. The presence of weeds favored the presence of parasitoids, reduced the population density of B. tabaci and the incidence of virus. Even when the presence of weeds delayed the incidence of virus, their presence also decreased the crop yield because of competition for resources. The selective presence of weeds should be planned in time and space, in order to protect the crop in its stage of most susceptibility to the viruses transmitted by B. tabaci.