Effect of water and glucose on the adult longevity ofNysius huttoniWhite (Hemiptera: Orsillidae)

The tolerance of adult Nysius huttoni to starvation, and the effect of water and glucose on the longevity of adults, were studied. When no food or water was provided, adults lived for an average of 2–4 days. Mean longevity of first-generation adults (4.2 days) was significantly greater than that of second- and third-generation adults (2.2 and 2.5 days respectively; P<0.05) suggesting that differences in resistance to starvation of adults between generations are influenced by the nutrient status during their nymphal development. There was no significant difference between longevity of male and female adults. When water alone was provided, mean adult longevity was 8.4 days. The effect of glucose on adult longevity was examined with the use of eight different glucose concentrations (2, 5, 10, 15, 20, 25, 30 and 40%) at 20±0.5 °C and 65–75% relative humidity (RH). Mean maximum longevity (49.0–51.6 days) was obtained at glucose concentrations of 10–20%, but decreased at higher (25–40%, 27.0–31.7 days) and lower (2–5%, 32.1–41.4 days) glucose concentrations. The relationship between longevity and the absorption and metabolism of glucose by N. huttoni adults is discussed.