New Pest Response Guidelines - aphis - US Department of Agriculture

Pest Information
Egg
Optimum temperature-humidity combination for PTL egg development was
established at 24°C and 80-85% relative humidity, with a range of 14 to 31°C
and a relative humidity between 40 to 98% resulting in only 5% egg mortality
(Kojima, 1933). Temperatures below 8.5°C and above 33.5°C result in 100%
mortality. Eggs developing at optimum temperature but high relative humidity
(more than 85%) will normally die because of high levels of potentially
pathogenic fungi growing on the surface (Kojima, 1933). However, eggs are
more tolerant to incubation at low relative humidity than high humidity
conditions. Incubation with relative humidity below 25% will result only in
15% to 18% mortality (Kojima, 1933). At optimal relative humidity, egg
development ranged from an average of 10 days at 31.5°C to 48 days at
11.5°C. At the optimum developmental temperature (24°C) and humidity (80-
85%) the average developmental time was 11 days. Egg size is another
important factor in the development of eggs. Small eggs will normally develop
faster than large eggs, possibly related to their nutritional content (Kojima,
1933).
Larva
In first instar larvae, the boundaries of tolerance for temperature and humidity
are more restricted than in the egg. A range of 18.0° to 26.5°C and of 55 to
100% relative humidity will result in 5% mortality. However, first instar larvae
will tolerate higher and lower temperatures (100% mortality above 37°C and
below 7°C) better than the eggs. First instar larvae are also more tolerant to
high humidity. Mortality due to pathogenic fungi is observed only when the
temperature is above 33°C and 100% relative humidity (Kojima, 1933). The
optimum larval developmental temperature and relative conditions was 24°C.
For other larval stages, the conditions were comparable to those of first instar
larvae (Kojima, 1933).
Pupa
Optimal temperature for pupal development is between 13 and 29.5°C and
relative humidity levels between 17% and 100%. Normal pupation is still
observed at 7°C. Pupal developmental time ranged from 95 days at 12°C to 14
days at 32°C. Developmental time was 25 days at 24°C (Kojima, 1933;
Winokur, 1991).
Dendrolimus punctatus
Limited information is available for the optimum developmental conditions of
MPC. The development period for each generation varies according to climate,
the number of generations and region.
12/2012-01 Dendrolimus Pine Moths 2-25