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271.
272.
Observations of search behavior in the predatory stinkbugPodisus maculiventris (Say) suggested that vibrations produced by prey as they chew on leaves may be an important cue used by this predator to locate prey. To test this hypothesis, studies were conducted to determine ifP. maculiventris search and make directional choices in response to vibrational stimuli produced by feeding green cloverworms,Plathypena scabra (F.), and to recordings of chewing vibrations. Modified soybean plants [Glycine max (L.)] were used in Y-choice tests. Individuals exposed to vibrational signals finished trials significantly more often on branches through which vibrations entered the plants than on no-stimulus branches. Also, a significantly higher proportion of individuals that initially moved onto branches with no stimulus reversed course than did those moving up branches with vibrational stimuli. The response ofP. maculiventris individuals to vibrational signals produced by a common prey species demonstrates that these predators are capable of using substrate-borne vibrations as cues for prey location. 相似文献
273.
Abstract. Female nocturnal bushcrickets ( Requena verticalis: Listroscelidinae: Tettigoniidae: Orthoptera) orientate towards and approach a conspecific male by tracking the direction of its call. If a male stops calling during this approach, the female may remain faithful and continue on the same track or change direction and pursue another calling male. Factors that might influence this decision were examined experimentally. When presented with a male call in conjunction with a visual cue, females maintained orientation towards the visual cue following cessation of the call. Furthermore, when a visual cue was presented with an acoustic cue, females were more likely to be faithful, regardless of call intensity. 相似文献
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275.
Females ofEphedrus cerasicola Stary were released into small glasshouses (13.6 m3) or cages (0.125 m3) which contained paprika plants in 2 of the following categories: fresh plants (without honeydew and aphids), honeydew-contaminated
plants (aphids removed) and aphid-infested plants (with honeydew). Two hundred females were released into each glasshouse
with 20 plants, 10 of each category, while 10 females were released into the cages with 2 plants, one of each category. Control
experiments with only fresh plants were conducted in both the glasshouses and the cages. The female parasitoids on each plant
were counted at regular intervals for 24 or 48 h in the glasshouse and for 4 h in the cage experiments; this number was used
as an indicator of plant preferences. The following preferences were established (preferred plant > less preferred plant):
honeydew-plant > fresh plant, aphid-plant > fresh plant, aphid-plant > honeydew-plant. The number of females on the aphid-plants
increased throughout the experimental period, whereas the number on the honeydew-plants tended to be more stable.
相似文献
276.
MARIA ROMSTÖCK-VÖLKL 《Ecological Entomology》1990,15(3):321-331
Abstract. 1. Larvae of Tephritis conura Loew (Diptera: Tephritidae) live gregariously in flower heads of Cirsium heterophyllum (L.) Hill (Cardueae). They are attacked by the endoparasitic wasps Eurytoma sp. near tibialis Boheman (Hymenoptera: Eurytomidae) and Pteromalus caudiger (Graham) (Hymenoptera: Pteromalidae).
2. The responses of the parasitoids to different host patch sizes were investigated from the analysis of field samples. At the host population level, overall probabilities of parasitism were independent of host numbers per flower head or showed a tendency to inverse density-dependence for both parasitoid species.
3. Measurements of ovipositor length in Eurytoma and P.caudiger indicated that parts of the flower head constitute a structural refuge from parasitism.
4. The accessibility of hosts in a flower head was found to differ markedly, depending on larval locations and flower head characters. In spite of this high variability, similar average percentages of larvae were accessible to the parasitoids in each patch size class.
5. High variability of oviposition success in laboratory experiments can be explained by random locations of hosts in the flower heads. 相似文献
2. The responses of the parasitoids to different host patch sizes were investigated from the analysis of field samples. At the host population level, overall probabilities of parasitism were independent of host numbers per flower head or showed a tendency to inverse density-dependence for both parasitoid species.
3. Measurements of ovipositor length in Eurytoma and P.caudiger indicated that parts of the flower head constitute a structural refuge from parasitism.
4. The accessibility of hosts in a flower head was found to differ markedly, depending on larval locations and flower head characters. In spite of this high variability, similar average percentages of larvae were accessible to the parasitoids in each patch size class.
5. High variability of oviposition success in laboratory experiments can be explained by random locations of hosts in the flower heads. 相似文献
277.
278.
《Current biology : CB》2022,32(20):4530-4537.e2
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279.
280.
AdultC. montrouzieri were able to detect their prey by visual and chemical stimuli. Presence of mealybug caused a significant increase in the
number of turns and a sharp decrease in flight attempts suggesting detection by olfaction. In the light, adult predators found
polystyrene dummies significantly faster than under dark (red light) conditions, but light had no effect on the time taken
for adults to pass across an invisible test point. Fourth instar larvae could only perceive the prey by physical contact.
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