Can. Ent. 121: 691-697 (1989) Electroantennogram (EAG) responses from male Cydia s~obilella (L.) indicated that (E)-8-dodecenyl acetate (E8-12:Ac) was the most stimulating of the dodecenyl and tetradecenyl compounds assayed. Field-screening tests, which included compounds previously reported as attractive, demonstrated that only E8-12:Ac was effective. The optimum trap dosage was 0.3-3 pg on red rubber septa. Catches of males were greater when traps were hung in the upper crown of either white spruce or black spruce.
RdsumdLes reactions tlectroantennographiques (EAG) des mfiles de Cydia strobilella (L.) ont indiqu6 que le (@-8-dodkce~yl acetate (E8-12:Ac) est le plus stimulant des composks dodkenyl6s et t6trad6cenyl6s test&. Des tests de terrain avec des compos6s rappods antkrieurement comme attractifs, ont d6montr6 que seul le E8-12:Ac est efficace. La dose optimale ttait de 0.3-3 pg sur septum de caoutchouc rouge. Les captures de miles Btaient plus Clev&s lorsque les piBges etaient suspendus dans la couronne sup6rieure que dans la partie inferieure, h la fois pour l'kpinette blanche et l'kpinette noire.
The contribution of larvae of the European pine sawfly, Neodiprionsertifer (Geoff.), to litter fall and element input was determined in two contiguous 25-year-old plantations of Scots pine (Pinussylvestris L.) near Glencairn, Ont., in 1972. Tree spacings were 1.2 × 1.2 and 1.8 × 1.8 m. Tree diameters, numbers of needle-bearing branches per tree, and the number of larval colonies per tree were greater in the less dense plantation. On the other hand, there was no difference between plantations with respect to tree height, number of needles per branch, number of larvae per colony, or percent defoliation. For the denser and less dense plantations, frass was the largest insect-derived component of litter fall at 804 and 1255 kg ha−1, respectively; needles constituted the major tree component of litter fall at 1107 and 929 kg ha−1, respectively, and the total combined contribution of tree and insect material to litter fall was 2395 and 2744 kg ha−1, respectively. Average element input (kilograms per hectare) to the soil via frass for the two plantations was greatest for nitrogen (6.9), followed by potassium (5.0), calcium (4.1), phosphorus (0.8), and magnesium (0.6).
The formation and final structure of the acrosome of the sperm of Lumbricus terresfris L. are described on the basis of an electron microscope study. The acrosome is compared with others described on the same basis, and it is concluded that invertebrate acrosomes form a series from simple to complex, with the Lumbricus sperm one of the most complex, both in manner of formation and in final structure.
White spruce trees were injected with a liquid formulation of dicrotophos (0.6 g Al/cm DBH) to evaluate the effect of injection times on cone and seed damage by insects. Injections of liquid formulations of dicrotophos (1.1 g Al/cm DBH) and oxydemetonmethyl (0.7 g Al/cm DBH) (approximately four days after the peak of flowering) were evaluated for control of defoliation and cone and seed damage by insects. Implants of a soluble powder formulation of acephate (0.5 and 1.0 g Al/cm DBH) (approximately two weeks after the peak of flowering) were evaluated for control of cone and seed damage. A single injection of dicrotophos reduced cone damage for up to four weeks after the peak of flowering by insects that oviposit and feed after pollination (seed moth, cone maggot, cone-axis midge, and seed inhabitants) whereas damage by insects that begin feeding before pollination was not reduced by single injections after pollination. Dicrotophos and oxydemetonmethyl reduced defoliation by spruce budworm at upper, middle, and lower crown levels for two seasons following injection. In the treatment year, these injections reduced the proportions of cones damaged by insects that feed after pollination whereas damage by insects that feed before pollination was not reduced; cone seed counts were increased 558% by dicrotophos and 267% by oxydemetonmethyl. In the season after injection the proportion of cones damaged by budworm was reduced by both insecticides while seed inhabitant damage was reduced by dicrotophos. Neither insecticide reduced damage by other insects; nonetheless, cone seed counts were increased 90% by dicrotophos and 115% by oxydemetonmethyl. In the year of treatment, implants of acephate reduced the proportions of cones damaged by seedmoth but not other insects whereas, in the season after implanting, they were effective against coneworm, seed moth, cone maggot, and seed inhabitants.
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