摘要:

Tests were conducted to increase the fecundity of a laboratory-reared colony of the tortricid moth,Bactra verutanaZeller. Moths were ca. 60% larger and the females laid ca. twice (1:1.9) as many eggs on a soy flour-wheat germ diet as onCyperus rotundusplants, but wing length was only 22% longer. Unfed males mated no more than once each 24 h and deposited seven spermatophores during an average life time of 9 days. By day 4 or 5 of life, one-third of the males could not fertilize more than an average 23% of the egg load of a virgin female. Female mating could be delayed 4 days after emergence before fecundity was affected. Females mated twice if newly emerged males were presented daily for 2 or 3 days. Unmated females deposited an average of ca. 27 eggs; mated females deposited 5 to 10 times as many eggs, with egg viability varying from 80 to 90%. Clipping two-thirds to three-fourths of one forewing to prevent flight did not reduce fecundity.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.181

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

The daily pattern of pollen-foraging activity ofApis melliferaL. was observed onZea maysL. from mid-July to mid-August at Newark, Del. Foraging occurred from 0600 to 1500 h (EDT), and the peak abundance of pollen-collecting bees was between 0900 and 1000 h on field and sweet corn. These data indicate that insecticide application to corn should be timed to avoid this peak foraging activity of the honey bee.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.187

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Preliminary mammalian safety tests were conducted on the entomopathogenic fungusMetarhizium anosipliae. No animals died or were clinically ill after injection of or exposure toM. anosipliae. There was no evidence of ocular irritation, and tissue lesions were confined to local sites at which large numbers of spores were collected. There was no histologic evidence of spore germination in mammalian tissues.M. anosipliaewas recovered from stomach, lung, and spleen after 2 weeks of exposure of mice to dusts but not at the end of week 3. Fungi were recovered also from focal granulomas that followed intraperitoneal injections ofM. anosipliaespores into rats. Fungi were recovered from spleens of rats given spores intraperitoneally, but the spleens were sterile 21 days after exposure.We concluded that our tests reveal no evidence of human or mammalian pathogenicity ofM. anosipliae.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.189

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Thirty-five insecticides used on rice in Asia were tested in the field againstNilaparvata lugens. The most important predators of the pest,Cyrthorhinus lividipennis,Microvelia atrolineata, and predacious spiders,Lycosa pseudoannulata,TetragnathaandAraneusspecies, were also momtored in the test plots. Ten insecticides significantly reduced numbers ofN. lugens, but propoxur and ethylan gave the most consistent and effective control. Most insecticides did not significantly reduce populations of spiders andM. atrolineatacompared with untreated checks, but they did reduce numbers ofC. lividipennis. Fifteen treatments caused resurgence ofN. lugens, resulting in significantly higher numbers in the treated plots than m untreated checks. Resurgence was apparently not caused by the toxicity of the materials against predators. Eleven of the insecticides had no effect onN. lugens.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.193

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Sticky-coated, non-ultraviolet-reflecting white rectangle traps (15 by 20 cm) hung from apple tree branches at ca. 70 cm above ground proved significantly more effective 10 detecting adult tarnished plant bugs(TPB),Lygus lineolaris(Palisot de Beauvois), than three other sampling methods: visual counts of adults on trees, limb jarring of adults onto a drop cloth, and net sweeps of ground cover vegetation. For 12 orchard situations in which no prebloom. insecticide treatments were applied, there were significant positive linear relationships between levels of TPB-injured fruit at harvest and cumulative trap capture levels through the tight-cluster (r2= 0.736) and late-pink (r2= 0.526) stages of flower bud development. If the economic injury level for TPB is considered to be 2.0% fruit damage, then our findings suggest a tentative action threshold of cumulative capture of 3.0 adults per trap through tight cluster or 4.4 adults per trap through late pink.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.200

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

In studies conducted in eastern Washington, seven species of weeds provided the food source of pre-overwintering lygus bugs,Lygusspp. The two major weed species were volunteer alfalfa,Medicago sativa, and lambsquarters,Chenopodiumspp. Winter survival of lygus bugs feeding on several species of weeds in the fall did not differ significantly. Winter survival of lygus bugs was low when the material in which the lygus bugs were overwintering was maintained under 10% of dry weight. Deciduous orchard duff was found to be the major overwintering site of adult lygus bugs, but considerable numbers overwintered in large mullein,Verbascum thapsisL., plants.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.204

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

The developmental responses ofSpodoptera eridania(Cramer)Pieris rapae(L.). fed onBrassica nigra(Koch) plants grown with four nutrient solutions were studied. When assayed, the plants from the different nutrient treatments (basic nutrient solution, low nitrogen, low sulfur, and 10% of basic nutrient solution) had dissimilar chemical profiles with respect to allylisothiocyanate concentration, protein concentration, and water content.S. eridaniagrew fastest on the low-sulfur plants and did not complete development on plants grown with the low-nitrogen or low-basic-nutrient solutions.P. rapaedeveloped most rapidly on the low-sulfur and low-nitrogen plants. The reasons for these developmental responses are discussed.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.207

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Chronic stunt virus (CSV) is a small, isometric RNA virus that specifically invades granular hemocytes of the navel orangeworm,Amyelois transitella(Walker). Although CSV was highly pathogenic to 1st-instar larvae in laboratory tests, 3rd-instar larvae usually acquired chronic disease that was characterized by retarded growth and a prolonged period of moribundity. The LC50for neonatal larvae challenged with surface applications of semipurified CSV was equivalent to 42 pg of larval homogenate per mm2. The slope of the calculated dosage-mortality regression was 0.75, which was indicative of the chronic nature of the disease. The rate of mortality was directly related to viral concentration. Weights and lengths of infected larvae exposed in the 3rd instar were inversely related to viral concentration and were significantly (P0.05) after 10 days of exposure to virus, although many infected larvae survived as long as 40 days. Mature control larvae were ca. eightfold heavier and twofold longer than diseased larvae of comparable age.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.214

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Lower aliphatic carboxylic acids are known to induce negative ovipositional responses in various species of mosquitoes. Straight-chain higher fatty acids from C5to C13and some of their methyl and ethyl esters and amides were evaluated for ovipositional activity in a laboratory olfactometer system against two species ofCulexand one species ofAedesmosquitoes. Of these higher acids, nonanoic acid (C9) was the most repellent againstC. quinquefasciatusandC. tarsalis, demonstrating significant repellency at 1 × 10−4M. Nonanoic acid was also the most active acid againstA. aegypti, significantly repelling the ovipositing mosquito at as low as 1 × 10−5M. Some of the higher acids, such as C8, C9, and C10acids, were as active as, or more active than, the lower acids from C2to C6against these three species of mosquitoes. Among the methyl and ethyl esters of C8to C10acids, only ethyl nonanoate showed considerable repellency. The amides of C8to C10acids did not exhibit any activity.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.223

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Lycoriella mali(Fitch) populations were exposed to mushroom compost that contained mushroom mycelium growth of various ages to determine whether the suitability of the compost for fly development was affected. It was found that unspawned compost was infested by flies and other invertebrate pests and that the more the compost was colonized by mushroom mycelium, the fewer theL. maliproduced. The reduction in flies was greatest after 12 days of mycelium growth. The type of compost apparently affected its suitability for fly development. Also, freshly made compost was less suitable forL. malithan aged compost. Large numbers of mites and nematodes were associated with fly infestations. This demonstration of the vulnerability of uncolonized mushroom compost to invertebrate pest attack could explain the variation in pest populations among different mushroom-growing facilities.

ISSN:1754-5692    

DOI:10.1093/ee/11.1.227

出版商:Oxford University Press    

年代:1982

数据来源: OUP