Zur Kenntnis der Kleinen Kiefern‐Buschhornblattwespe, Diprion (Microdiprion) pallipes (Fall.) (Hym., Diprionidae)

Abstract

Contributions to the Knowledge of Diprion (Microdiprion) pallipes (Fall.) (Hym., Diprionidae). Part 2: Bionomy and Ecology. Part 2 contains the results of biological and ecological studies on eggs, larvae, cocoons and adults of the sawfly. The inclination of the sawflies to copulate was very low. The size of egg pods as well as the distribution of eggs on the needles depended on pine species, length of needles, locality and constitution of trees. The average number of eggs located in the needles of a twig amounted to 34.6 ± 16.4 (n = 119). The female laid an average number of 63 eggs during its life time. The male larvae run 4, the female 5 Stages. There were 2 generations per year. Zero of development of eggs amounted to 8.8° C; the thermal constant (K) for the development of eggs amounted to 119 and that of larvae to 272. The eggs hatched of 7 days (26° C). The larval period was completed in 16.5 days (26–27° C, Pinus silvestris). The average quantity of food consumed by a male larva on Pinus silvestris during its life span amounted to 500 mg. The female larva consumed about 1.7 times more than a male larva. The cocoons of the first generation were spun on buds and needles of pines. The cocoons of the second generation overwintered in or near the soil. The duration of the eonymphal stage in the cocoon (diapause) was mainly determined by the photoperiod effecting upon the old larvae.

Effects of temperature on predation by the stinkbugsPicromerus bidensandPodisus maculiventris(Heteroptera: Pentatomidae) on noctuid caterpillars

“…Although some studies have reported on the capacity of P. bidens to reduce populations of insect pests (e.g. Gäbler, 1937Gäbler, , 1938Engel, 1939;Clausen, 1940;Forsslund, 1946;Pschorn-Walcher & Zinnert, 1971;Mallach, 1974;Volkov & Tkacheva, 1997), the potential of this predator for augmentative biological control is largely unknown.…”