Bionomics And Ecology Of The Erythrina Gall Wasp, Quadristichus Erythrinae Kim

The erythrina gall wasp Quadrastichus erythrinae Kim, an important quarantine pest, has caused severe damage in Singapore, Mauritius, Reunion, American Hawaii, and also in Taiwan, Shenzhen, Xiamen of China recently. This paper dealt with the bionomics and ecology of Quadrastichus erythrinae Kim both in laboratory and in field. The main research results are as follows.Under laboratory condition, the eclosion of Quadrastichus erythrinae Kim happened between 6:00 am and 14:00 pm with the eclosion peak appeared in 8:00 am. The developmental duration became shorter with the temperature increased, and the forecast formulas of egg, larva, pupa areThe average number of eggs born by a female were 119.33 eggs with highest at 24℃. The assumed relationship formulas between the pregnant eggs(y) and temperature (x) is y=-1. 5637x~2+75. 295x-786. 09, R~2=0. 9397. Moreover the adult activity of the gall wasp were related significantly to light.Humidity could affect the longevity of Quadrastichus erythrinae Kim and the assumed relationship formulas between the female longevity (y) and humidity (x) is y =-0. 006x~2 + 0. 8374x - 20. 389 , R~2 = 0.9601; and that between the male longevity(y) and humidity(x) is y=-0. 0038x~2+0. 5749x -16.128, R~2=0. 9286.The female longevity was prolonged by supplementary nutrition, but the male not. The sex ratio also changed with environmental temperature.The thermal threshold and the effective accumulated temperature for Quadrastichus erythrinae Kim were 14.47℃and 338. 45 degree-days respectively.