Abstract
Mortality responses of 3-d-old eggs and 1st, 3rd, and 5th instars of 6 New Zealand tortricids to 2 controlled atmospheres (1.2% O 2 and 4.2% O 2 with 5% CO 2 at 40°C) and 40°C air were determined. Endemic species, Ctenopseustis obliquana (Walker), Ctenopseustis herana (Felder and Rogenhofer), Planotortrix excessana (Walker), Planotortrix octo Dugdale, and Cnephasia jactatana (Walker), all exhibited similar mortality responses, with a common pattern of increasing time LT 99 as the oxygen level increased (1.2% O 2 atmosphere ≤ 4.2% O 2 atmosphere ≤ air). Typically, 3-d-old eggs were more susceptible to treatment than larval stages tested. However, this pattern lessened with increasing O 2 concentration of treatment in three species. All endemic leafroller species were sensitive to the high treatment temperature. Collectively (over all life stages tested), the LT 99 never differed by > 3.9 h within a single treatment or by 4.6 h over all 3 treatments. Whereas Epiphyas postvittana displayed a similar order of increasing tolerance to treatment (1.2% O 2 atmosphere 1st instars 3-d-old eggs. Only LT 99 s of 3rd and 5th instar E. postvittana exceeded those of their endemic counterparts. Mean LT 99 values for 5th instar E. postvittana to the 1.2% O 2 atmosphere, 4.2% O 2 atmosphere and air treatments were 8.5, 15.5, and 21.1 h, respectively.
Published Version
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