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1.
Okoli B. E. etNyananyo B. L. (1988): Palynology ofTelfairia L. (Cucurbitaceae).—Folia Geobot. Phytotax., Praha, 23: 281–283.—Scanning and transmission electron microscopic studies were carried out on the pollen of the two species ofTelfairia, T. pedata (Sims.) Hooker andT. occidentolis Hooker fil. Pollen grains in both species are spheroidal, tricolporate and tectate. The extexine is finely reticulate. The tectum, foot layer and columellae are all well developed. Significant differences of taxonomic value do not exist in the structure of the pollen of the two species.  相似文献   
2.
We compared the calling and mating behavior and volatile release of wild males Anastrepha ludens (Loew) with males from 4 mass‐reared strains: (i) a standard mass‐reared colony (control), (ii) a genetic sexing strain (Tap‐7), (iii) a colony started from males selected on their survival and mating competitiveness abilities (selected), and (iv) a hybrid colony started by crossing wild males with control females. Selected and wild males were more competitive, achieving more matings under field cage conditions. Mass‐reared strains showed higher percentages of pheromone calling males under field conditions except for Tap‐7 males, which showed the highest percentages of pheromone calling males under laboratory cage conditions. For mature males of all strains, field‐cage calling behavior increased during the last hour before sunset, with almost a 2 fold increase exhibited by wild males during the last half hour. The highest peak mating activity of the 4 mass‐reared strains occurred 30 min earlier than for wild males. By means of solid phase microextraction (SPME) plus gas chromatography‐mass spectrometry (GC‐MS), the composition of volatiles released by males was analyzed and quantified. Wild males emitted significantly less amounts of (E,E)‐α‐farnesene but emitted significantly more amounts of (E,E)‐suspensolide as they aged than mass‐reared males. Within the 4 mass‐reared strains, Tap‐7 released significantly more amounts of (E,E)‐α‐farnesene and hybrid more of (E,E)‐suspensolide. Differences in chemical composition could be explained by the intrinsic characteristics of the strains and the colony management regimes. Characterization of calling behavior and age changes of volatile composition between wild and mass‐reared strains could explain the differences in mating competitiveness and may be useful for optimizing the sterile insect technique in A. ludens.  相似文献   
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The moth Tecia (Scrobipalpopsis) solanivora Povolny (Lepidoptera: Gelechiidae) is the most important pest of potato, Solanum spp., in Central America and adjacent South American countries. Insecticide treatments are not sufficiently effective; therefore, we investigated the feasibility of pheromone-mediated mating disruption for control of T. solanivora. Pheromone dispensers were formulated with 70 mg of the three sex pheromone compounds (E)-3-dodecenyl acetate, (Z)-3-dodecenyl acetate, and dodecyl acetate, in a ratio of 100:56:100, respectively. Male attraction to these compounds is optimal at a ratio of 100:1:20, thus the mating disruption dispensers contained an off-blend, which attracted only a few males. Nonetheless, one mating disruption dispenser suppressed male attraction to calling females in a flight tunnel and reduced male activation in response to female pheromone. Communication disruption is accordingly due to camouflage of the female signal and possibly due to a reduction of male responsiveness by sensory imbalance. Only a few males were observed in a 3-ha potato field treated with 84 g pheromone/ha, compared with an untreated control field. During 2 mo, male attraction to traps baited with calling females or synthetic pheromone was strongly reduced. This reduction confirms the potential of mating disruption for management of T. solanivora. The efficacy of the pheromone treatment can be further improved by earlier dispenser application, by increased dispenser load, and by treatment of larger fields to reduce immigration of mated females.  相似文献   
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Due to rapid advances in genetic engineering, small rodents have become the preferred subjects in many disciplines of biomedical research. In studies of chronic CNS disorders, there is an increasing demand for murine models with high validity at the behavioral level. However, multiple pathogenic mechanisms and complex functional deficits often impose challenges to reliably measure and interpret behavior of chronically sick mice. Therefore, the assessment of peripheral pathology and a behavioral profile at several time points using a battery of tests are required. Video-tracking, behavioral spectroscopy, and remote acquisition of physiological measures are emerging technologies that allow for comprehensive, accurate, and unbiased behavioral analysis in a home-base-like setting. This report describes a refined phenotyping protocol, which includes a custom-made monitoring apparatus (Integrated Behavioral Station, INBEST) that focuses on prolonged measurements of basic functional outputs, such as spontaneous activity, food/water intake and motivated behavior in a relatively stress-free environment. Technical and conceptual improvements in INBEST design may further promote reproducibility and standardization of behavioral studies.  相似文献   
7.
Chemical analysis of pheromone gland extracts followed by behavioural studies in the wind tunnel and by field trapping tests show that the sex pheromone of the Guatemalan potato moth, Tecia (Scrobipalpopsis) solanivora Povolny (Lepidoptera: Gelechiidae), is a blend of (E)‐3‐dodecenyl acetate, (Z)‐3‐dodecenyl acetate, and dodecyl acetate. A 100 : 1 : 20 blend of these compounds, formulated at 1000 µg on rubber septa, captured more males than the main compound alone. This lure was species‐specific and did not capture the potato tubermoth, Phthorimaea operculella. A potato field was treated with a blend of these three compounds at a rate of 28 g ha?1. Male T. solanivora attraction to synthetic pheromone traps was almost completely suppressed for 2 months, demonstrating the potential use of pheromones for control of this economically important insect pest of potato in Central and Southern America.  相似文献   
8.
Chromosome counts onCostus lucanusianus in Nigeria were carried out. Diploid (2n=18) and triploid (2n=27) chromosome numbers were found. The diploid cytotype is reported for the first time for this taxon.  相似文献   
9.
The family Cucurbitaceae is represented in Nigeria by 21 genera, many of which are of considerable economic importance. Certain genera, such asTelfairia, Cucurbita andCitrullus, are commonly cultivated in southern Nigeria since their fruits and/or leaves constitute important items in the local diet. Other genera are significant as oil plants, medicinal plants, sources of tanning materials, sponges and household utensils.  相似文献   
10.
Summary The enzymatic transformation of desacetyl-lanatoside A (DLA) to its secondary glycoside, digitoxin, in solutions of -and -cyclodextrins is effected using of -glucosidase from barley. Due to the interaction of cyclodextrins (CyDs) with desacetyl-lanatoside A, an increase in solubility of the latter of 24.5 and 230 times was observed for -cyclodextrin and -cyclodextrin, respectively. Kinetic studies of the enzymatic transformation gave for -glucosidase the values KM=3.3×10–4 mol. dm–3 and Vmax=0.557 mol mg–1 min–1 when the substrate was the deacetyl-lanatoside A complex with -cyclodextrin, while in the case of the complex with -cyclodextrin these values were KM=5.45×10–4 mol dm–3 and Vmax=0.896 mol mg–1 min–1.  相似文献   
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