Ocorrência de formas aladas de pulgões e sua relação com fatores meteorológicos e plantas hospedeiras

Abstract

Resumo -O objetivo deste trabalho foi determinar o padrão de revoadas e a infl uência de fatores meteorológicos e de Brassicaceae sobre populações de formas aladas dos pulgões Brevicoryne brassicae, Lipaphis erysimi e Myzus persicae. Os pulgões foram amostrados em armadilhas tipo bandeja amarela com água, entre julho de 1997 e agosto de 2005. A correlação parcial de Pearson foi utilizada para verifi car a infl uência da temperatura do ar, umidade relativa, chuva e insolação na abundância de alados das três espécies. A infl uência de brassicáceas foi avaliada pelo cálculo do número de graus-dia acumulados acima da temperatura base inferior dessas plantas. Lipaphis erysimi foi mais numerosa que M. persicae e B. brassicae. Os alados de B. brassicae apresentaram revoadas que predominaram de agosto a outubro, com o pico de abundância em setembro. Os períodos de revoada de L. erysimi e M. persicae foram mais longos que o de B. brassicae, com os maiores picos de L. erysimi e M. persicae observados de abril a novembro e de junho a outubro, respectivamente. A população de B. brassicae teve correlação signifi cativa com as temperaturas máxima e mínima, insolação e umidade relativa do ar, enquanto L. erysimi e M. persicae foram afetadas apenas pela insolação e umidade relativa.Termos para indexação: Brassica oleracea, dinâmica populacional, dispersão, padrão de revoada, pulgão. Occurrence of alate aphids and their relationship with meteorological factors and host plantsAbstract -The objective of this work was to determine the fl ight patterns and the infl uence of meteorological factors and Brassicaceae on the populations of the alate aphids Brevicoryne brassicae, Lipaphis erysimi and Myzus persicae. The alate aphids were sampled using yellow water traps between July of 1997 and August of 2005. The Pearson partial correlation was used to determine the infl uence of air temperature, relative humidity, rainfall and insolation on the abundance of alate. The infl uence of Brassicaceae was assessed by accumulated degree-days above the temperature threshold of these plants. Lipaphis erysimi was more abundant than M. persicae and B. brassicae. The alate B. brassicae showed the highest fl ight frequency between August and October, with the abundance peak in September. The fl ight frequency of L. erysimi and M. persicae were longer than B. brassicae, with the alate abundance peaks of L. erysimi and M. persicae observed from April to November and from June to October, respectively. The population of B. brassicae showed signifi cant correlation with the maximum and minimum temperatures, insolation and relative humidity, while L. erysimi and M. persicae were only affected by insolation and relative humidity.

Predicting the occurrence of alate aphids in Brassicaceae

“…These species also showed the same predictor, i.e., number of days with rainfall. This result is in accordance with Cividanes & Santos-Cividanes (2010), which reported that L. erysimi and M. persicae showed similar flight dynamics, differing from B. brassicae. These authors also found that B. brassicae showed a significant correlation with maximum and minimum temperatures, sunshine hours, and air relative humidity, whereas L. erysimi and M. persicae were only affected by sunshine and relative humidity.…”

“…According to Cividanes & Santos-Cividanes (2010), the occurrence of the alate B. brassicae was restricted from May to October-November, and no specimens were captured from December to April of the following year. However, the alates L. erysimi and M. persicae were observed for a longer period than B. brassicae, especially L. erysimi, which was captured in most of the evaluated months.…”

“…The prediction of aphid occurrence was evaluated by comparing the dates of population peaks predicted by the model to dates of peaks observed in the field (Cividanes & Santos-Cividanes, 2010). The differences in days (lags) between the dates of the predicted peaks and the ones observed in the field indicate the accuracy of the prediction.…”