Estimation of development threshold and thermal requirements of Jujube lappet moth Streblotesiva (Lefebvre)

Streblo tesiva (Lefebvre) (Lepidoptera: Lasiocampidae) is one of the important potential pest as a defoliator on Acacia ampliceps, Ziziphus spp. and Conocarpus erectus of ornamental and forest communities in south of Iran. Temperature-dependent development of the egg, larval, and pupal life-stages of S. siva was investigated at four constant temperatures of 15.0, 20.0, 25.0 and 30.0˚C using data collected from constant-temperature laboratory experiments under controlled conditions (65±5% RH, 12L: 12D). Data were adjusted to the linear degree-day model and Ikemoto and Takai model to describe the effect of different temperatures on the developmental rate of the life-stages. The results showed the average hatching time was 19.52±0.49 and 6.34±0.20 days at 15 and 30 ˚C, respectively. The duration of each stage decreased with increasing in the temperature up to 30 °C, so that when the temperature was rose up from 15 to 30˚C, the average larval development times decreased from 119.43±3.46 to 36.52±0.70 days. The pupal period development time ranged from 37.07±0.88 to 9.32±0.28 days at 15 and 30˚C respectively. The egg-to-adult development time took place in the range from about 176.30±3.58 until 52.12±0.71 days. The developmental thresholds for egg, larval, pupa and egg-to-adult stage development were 8.97, 7.77, 12.20 and 8.59˚C in liner general model and 9.24, 10.34, 11.12 and 10.48˚C in Ikemoto and Takai model, respectively. According to the linear model, the thermal constant was 1023.54±34.57 degree days, and 920.86±22.59 degree days in liner general and Ikemoto and Takai models respectively