Flutuação populacional de RHOPALOSIPHUM MAIDIS (HEMIPTERA: APHIDIDAE) na cultura do milho.

Abstract

The population fluctuation of insects in a given culture is closely linked to biotic and abiotic factors of the environment in which they live. In agroecosystems, the imbalance of a given insect population can lead to irreparable economic losses. The objective was to measure the population fluctuation of the corn aphid, Rhopalosiphum maidis Fitch, 1856 (Hemiptera: Aphididae), in the corn crop in the municipality of Nossa Senhora da Glória, Sergipe, Brazil. To carry out this study, corn plants were evaluated fortnightly from 15 to 140 days after emergence. The experimental area was 1 ha, divided into two crops and a total of 86 sampling points. The method used was non destructive sampling and the sampling technique was direct counting using walking at uniformly distributed points in the area. The population of aphids and enemies was higher in the R1 and R2 maize reproductive stages for the two evaluated crops and in periods of little precipitation. Regarding the faunistic analysis, there was no significant difference between crops. Regarding the aphid density and natural enemies with the environmental variables there was a significant difference. It can be concluded that the influence of abiotic factors on the population of aphids and natural enemies was observed, which emphasizes the importance of understanding the population fluctuation of the pest R. maidis, in order to develop policies for an integrated, efficient and sustainable management.