Diapause induction in field populations of the codling moth,Cydia Pomonella, in Northern Israel

Diapause induction in the codling moth, Cydia pomonella: effect of prediapause temperatures

“…2). These findings verify the evidence from field observations (Steinberg et al, 1988). Further- Danks (1987).…”

“…Further- Danks (1987). more, the natural mean day length and temperature in August, the month that includes the dates of CPhPso for field populations (Steinberg et al, 1988), is fairly close to the pattern found in the present study (Fig. 2).…”

“…In addition, the fact that CPhPs0 at 26 ~ was higher than at 22 ~ (Table 2, Fig. 2), also agrees with field data: during August and September in the valley (mean temperatures of 26.4 and 25 ~ C, respectively), diapause incidence preceded that of the mountain region with mean temperatures of 24 and 22 ~ during the same months, respectively (Steinberg et al, 1988).…”

“…This correlation is further strengthened when comparing the relatively low rates of diapause recorded at 18 ~ under laboratory conditions with the field observations: in the valley, the combination of short days during March and April (means of 12.39 and 13.79 h, respectively) and low temperatures (means of 14.4 and 17.85 ~ respectively), yielded less than 5~o diapause. Similarly, in the mountain region, day length means of 13.79 and 14.67 h during April and May, respectively and mean temperatures of 15.62 and 19.07 ~ C, respectively, induced less than 5 ~o diapause in field populations of the codling moth (Steinberg et al, 1988). In addition, the fact that CPhPs0 at 26 ~ was higher than at 22 ~ (Table 2, Fig.…”

“…Indirect evidence from an extended field study suggested that prediapause temperature might modify diapause induction in the Israeli strain of the coding moth (Steinberg et al, 1988). A series of controlled experiments was therefore conducted in order to elucidate the effect of prediapause temperature.…”