摘要:

Traps hung on small trees of 3–8 cm diam and baited with racemic epoxides, hydrocarbons and other analogues related to racemiccis-7,8-epoxy-2-methyloctadecane (disparlure) resulted in maleLymantria disparL. (gypsy moth) catches statistically indistinguishable from those of unbaited traps. Only (±)-disparlure yielded trap catches statistically above the level of unbaited traps. However, trap placement on trees of ca. 0.5 m diam produced appreciable trap catches, even in unbaited traps.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.765

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

Synthetic attractant lures enriched in the (+) enantiomer ofcis-7,8-epoxy-2-methyloctadecane were many times more effective in eliciting trap catch of male gypsy moth,Lymantria dispar(L.), than racemiccis-7,8-epoxy-2-methyloctadecane. The lowered trap catch at the racemate was due to the antagonistic effects of the (−) enantiomer on the male behaviors of long-range upwind flight, the likelihood of landing on the baited trap and duration of the persistent “searching” behavior of wing fanning concurrent with walking on the trap. The admixture of 2-methyl-(Z)-7-octadecene with the (+) enantiomer also effected a reduction in trap catch.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.768

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

AlthoughTelenomus alsophilaeViereck is important in the natural control of a hardwood defoliator,Alsophila pometaria(Harris), its parasitization capabilities and host range are largely unknown. Initially, eggs of a laboratory host,Abbotana clemataria(J. E. Smith), were exposed to mated females each day from deposition till eclosion. Although eggs during all stages of development were attacked, only unembryonated eggs were parasitized successfully. Infertile eggs of the same host also were parasitized but less effectively than comparable numbers of fertile eggs. Among 22 prospective hosts in 5 families of Lepidoptera,T. alsophilaeparasitized 12 species of geometrids and 2 of noctuids. It was concluded that the broad host potential for this parasite offers some new opportunities for biological control work against forest pests that previously were not anticipated.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.773

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

The survival ofHippodamia convergensGuérin-Méneville on grain sorghum,Sorghum bicolor(L.) Moench, in the Texas High Plains was investigated. Analysis of survivorship data revealed that most of the generation mortality occurred in the egg or early larval stage. This reduces the effectiveness ofH. convergensas an aphid predator in grain sorghum because the predator either does not survive to feed at all or feeds for only a fraction of its developmental time.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.777

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

Host seeking activity by female tabanids was measured in wooded areas, and in open areas and pastures near woods by trapping blood meal seeking tabanid females, collections from a bait animal, and observation of fluorescent marked flies. Studies were conducted in 3 areas of South Louisiana during the summers of 1973–74. Tabanid host seeking activity was significantly higher in open areas within 130 m of woods than 15–18 m or more into the woods or 237 m or greater from the woods' edge in the open.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.781

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

The major parasites of cabbage looper larvae in California cotton areHyposoter exiguae(Viereck),Microplitis brassicaeMuesebeck, andCopidosoma truncatellum(Dahlman). Parasitization for a given species was greater when the species occurred alone than when it occurred in combination with one or two other species. However, total parasitization did not decrease with an increase in number of parasite species. Implications for multiple-species introductions are discussed.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.783

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

The foraging distance, distribution patterns, and pollen collection were compared for Hy-Queen, diminutive-wing mutant, and common Italian stocks placed near fields of onion (Allium cepaL.) and safflower (Carthamus tinctoriusL.). A greater percentage of Hy-Queen bees foraged at nearby onion plots compared to more distant safflower plots. There was no significant difference in the frequency of onion pollen collection of Hy-Queen and common stock.Hy-Queen and diminutive-wing bees foraged closer to their colonies than did common stock, indicating that genetic regulation of foraging distance may be a feasible method to concentrate bees in areas where intensive pollination is required.A method is given that permits the comparison of foraging distances of individual colonies, or sub-populations therein.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.785

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

Density of the red pine scale,Matsucoccus resinosaeB and G (Homoptera: Margarodidae), and the related resinosis of its host,Pinus resinosaAit., in a Connecticut plantation had a profound influence on scale biology, behavior, and population dynamics. Fecundity of the fall, 1975 generation was positively correlated with the density of feeding nymphs on 9 trees. During development of the subsequent summer, 1976 generation, the most heavily infested trees began to secrete resins from feeding wounds. Nymphs feeding on these trees required 2–3 wk longer to mature and females produced significantly fewer eggs than their mothers.Overwintering mortality was greatest among nymphs in the early substages of the 1st instar and among nymphs which colonized 1- and 2-yr-old growth. Since nymphal development was prolonged on heavily infested trees, a proportionately greater number of 1st-instar nymphs overwintered in earlier substages of development. Also, resinosis at the preferred colonization sites (3-yr-old growth) on these heavily infested trees forced crawlers to settle on the less desirable young growth. Consequently, nymphs on heavily infested trees suffered a greater percent overwintering mortality than did nymphs on less heavily infested trees.Dispersal ofM. resinosaecrawlers was density-dependent.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.789

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

Telenomussp., and to a lesser extent,Trichogrammasp., were important in the regression phase of a gradation ofSymmerista canicostaFranclemont, the so-called redhumped oakworm. Two years following the outbreak,Telenomusparasitized more than 80% of the eggs near ground level. When parasite populations were moderate,Telenomustended to be most abundant near ground level whereasTrichogrammatended to be most abundant in the upper parts of the forest. When populations ofTelenomuswere dense, parasitization was high at all levels in the forest. Both parasites successfully parasitizedS. canicostaeggs in the laboratory.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.796

出版商:Oxford University Press    

年代:1977

数据来源: OUP

摘要:

The study of insect-pest management systems requires knowledge of the effectiveness of applied insecticides. The study reported here was conducted to develop a method to estimate insecticide induced mortality of an insect population depending on the rate of application, the persistence of the insecticide, a dosage-mortality relationship, and the time of exposure of the insects to a treated area. A logarithmic equation was developed to estimate the cumulative percent mortality with time. The model was validated using mortality data for boll weevils,Anthonomus grandisBoheman, exposed to 2 rates each of azinphosmethyl and methyl parathion. The method developed in this paper can be used to study insect population dynamics as affected by the timing and rates of insecticide applications, increasing insect resistance to insecticides, and the use of different insecticides.

ISSN:1754-5692    

DOI:10.1093/ee/6.6.799

出版商:Oxford University Press    

年代:1977

数据来源: OUP