Papel da aclimatação na sobrevivência, reprodução e resposta funcional de Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae)

Abstract

The maximum biotic potential of insects requires an adequate supply of nutrients and an optimum range of humidity and temperature. However, the insects can acclimate in an environment outside this range, which provides an adaptive performance under stress conditions. In this work, we investigated the acclimation, survival, and reproduction of the ladybeetles Tenuisvalvae notata (Mulsant) (Coleoptera: Coccinellidae) under conditions of low (12, 14, 16 and 18ºC) and high (32, 34 and 36ºC) temperatures. We estimated the rate of predation and functional response of acclimated ladybeetles feeding on mealybug Ferrisia dasylirii (Cockrell) (Hemiptera: Pseudococcidae). Finally, we investigated the possible effect of temperature on adult sterilization. The acclimation favored the survival of the ladybeetles, under the high and low temperatures. However, despite remaining alive after acclimation, there was a significant reduction in fecundity below 18°C and above 34 °C. In general, there was no effect of temperature on the predatory capacity of T. notata, maintaining a type II functional response. However, above 32°C there was a reduction in the handling time of the prey. Fertility was reduced when females or males were acclimated to high (32°C) and low (18°C) temperatures, but females under low temperatures was more affected. From the previous acclimation, it is possible that T. notata is introduced in areas with the temperature outside the optimal range of development and maintains its predatory capacity in that location. However, expected it is a decline in the T. notata population due to reduced reproduction of acclimated insects.