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Ruurd de Jong Nevile Maher Bruno Patrian Erich St?dler Tammo Winkler 《Chemoecology》2000,10(4):205-209
Summary. Two recently identified compounds ("CIFs"), present on the leaf surface of Brassica oleracea (cabbage), are the strongest oviposition stimulants known for the cabbage root fly, Delia radicum. Cabbage leaves contain these compounds in extremely low concentrations, and the amount of CIFs obtained from purifying leaf
extracts was so small that it limited further research. We were able to purify far more of these two compounds from the roots
of Brassica napus var. napobrassica (rutabaga). Apart from being a richer source of CIFs, rutabaga roots are considerably easier to collect and process than
leaves. In addition, we isolated and identified a new CIF compound from the roots that is also very active in stimulating
oviposition in the cabbage root fly.
Received 26 May 2000; accepted 26 July 2000 相似文献
204.
Alison M. Barker Reitumetse Molotsane Caroline Müller Urs Schaffner Erich Städler 《Chemoecology》2006,16(4):209-218
Summary. The turnip sawfly Athalia rosae sequesters glucosinolates from its cruciferous host plants in the larval stage. Investigation of the chemosensory and behavioural
responses of adult A. rosae to glucosinolates and their volatile hydrolysis products, isothiocyanates, revealed that females detect glucosinolates by
contact chemoreception and isothiocyanates by antennal olfaction. In electroantennogram recordings, four isothiocyanates (allyl
[2-propenyl] isothiocyanate, benzyl isothiocyanate, butyl isothiocyanate and iberverin [3-methylthiopropyl isothiocyanate])
were active at all doses presented, including the lowest (0.1 μg), whilst the threshold for detection of three others, iberin
[3-methylsulphinylpropyl isothiocyanate], methyl isothiocyanate, and sulforaphane [4-methylsulphinylbutyl isothiocyanate],
was higher, at between 1 and 10 μg (source concentration of volatiles). Allyl isothiocyanate attracted experienced females
in a four-chambered olfactometer, whilst na?ve females showed no response. Allyl isothiocyanate also attracted mature females
to baited yellow water traps in field trials, although immature females were repelled at high isothiocyanate concentrations.
In laboratory behavioural bioassays the glucosinolates sinigrin (allyl [2-propenyl] glucosinolate) and sinalbin (p-hydroxybenzyl
glucosinolate), stimulated ovipositor probing in mature female A. rosae to an extent comparable to hot-water extracts of their host plants. These responses show that glucosinolates and isothiocyanates
play an important role in host finding and host recognition in A. rosae. 相似文献
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Summary. Delia antiqua (Diptera: Anthomyiidae) females lay eggs between the leaves of onion plants or in the soil around the base of the plants,
then the maggots feed on the onion bulb and roots causing rapid secondary infection by fungi and bacteria. It is well known
that the first sensory modality used by the onion fly is vision, therefore the shape (vertical narrow cylinders) and colour
(yellow) of the plant play a crucial role in the recognition of a potential host plant. In the past it has been shown that
n-dipropyl disulfide (Pr2S2), a typical component of onion volatiles, is an important chemical host plant cue. We extracted host leaf surface to verify
if Pr2S2 is the major chemical oviposition stimulant and to determine if other as yet unknown substances may play a role in host-plant
selection. We confirmed that the females laid more eggs around onion plants with leaves than when only the onion bulb was
present and that the odour of chopped onion stimulates oviposition. Extraction of the surface of onion leaves revealed that
only the apolar fraction contained substances that stimulate egg-laying in D. antiqua. GC-EAD analysis indicated that a minor constituent, Pr2S2, is perceived by the olfactory receptor on the antennae of the onion fly females. This confirmed the importance of Pr2S2 as oviposition stimulant. Contact with the polar fraction did not stimulate egg-laying behaviour in this Delia species. We discuss the oviposition strategy of D. antiqua in comparison with its closely related species, D. radicum, in which the oviposition behaviour is stimulated mainly through contact with the cabbage leaf surface and only partially
by the host volatiles. 相似文献
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