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Stewart Z. Merritt 《Journal of chemical ecology》1996,22(6):1133-1145
Although within-plant variation in the nutrient and allelochemical composition of phloem sap has been invoked to explain patterns of host use by phloem-feeding insects, little is known about within-plant variation in phloem chemistry. Here I describe a new technique in which I use the green peach aphid,Myzus persicae Sulz., to investigate within-plant variation in the concentrations of chemicals in the phloem sap of black mustard,Brassica nigra (L.) Koch (Cruciferae). Relationships between the concentrations of chemicals in aphid diets and honeydew were established using honeydew from aphids fed on artificial diets with known concentrations of amino acids, sucrose, and sinigrin. These relationships were applied to honeydew from aphids fed on different aged leaves of black mustard to estimate the concentrations of the chemicals in phloem sap. Sinigrin concentration was estimated to be high (>10 mM) in phloem sap in young leaves, calling into question the prevailing opinion that phloem sap contains only low concentrations of allelochemicals. High concentrations may function as defenses against sap-feeding herbivores. Within-plant variation in phloem sap composition was high: (1) young leaves had high concentrations of nutrients (216 mM amino acids, 26% sugar) and sinigrin (>10 mM); (2) mature and presenescent leaves had lower concentrations of nutrients (77–83 mM amino acids, 19–20% sugar) and low concentrations of sinigrin (1–2 mM); and (3) senescing leaves had high concentrations of nutrients (199 mM amino acids, 25% sugar) and low concentrations of sinigrin (3 mM). 相似文献
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Y. Asakawa G. W. Dawson D. C. Griffiths J. -Y. Lallemand S. V. Ley K. Mori A. Mudd Massoume Pezechk-Leclaire J. A. Pickett H. Watanabe Christine M. Woodcock Zhang Zhong-Ning 《Journal of chemical ecology》1988,14(10):1845-1855
A series of natural drimanes and related synthetic compounds was tested for antifeedant activity against aphids. Polygodial and warburganal were the most active. The synthetic compounds methyl 9-hydroxydrimenoate and 9-hydroxydrimenal, although active against lepidopteran larvae, were inactive against aphids. Natural (–)-polygodial and the synthetic (+) isomer showed similar levels of activity as aphid antifeedants and in phytotoxicity, fish toxicity, and human taste tests, but reacted at different rates with enantiomers of 1-phenylethylamine. 相似文献
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在12个晒红烟品种(泉烟等)和2个烤烟品种NC89(对照品种)及红花大金元的盆栽试验中,用微笼研究了烟蚜的生命表以了解生殖力和死亡率.并对某些种群参数作出统计分析。饲养条件为20.0℃—31.1℃.相对湿度为72%-92%。获得了以下参数:净生殖率(R0),内禀增殖力(rm),平均世代历期(T)(d)及周限增长率(λ)。表明烟蚜在4个品种上(NC89、红花大金元、剑叶子、安88)发生数量较少,而在3个品种上发生多(大花>柳叶子>小花青)。方差分析表明,生殖力及死亡率在品种间均有显著差异。 相似文献
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The vast majority of studies of plant indirect defense strategies have considered simple tritrophic systems that involve plant
responses to attack by a single herbivore species. However, responses by predators and parasitoids to specific, herbivore-induced,
volatile blends could be compromised when two or more different herbivores are feeding on the same plant. In Y-tube olfactometer
studies, we investigated the responses of an aphid parasitoid, Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae), to odors from cabbage plants infested with the peach-potato aphid Myzus persicae (Sulzer) (Homoptera: Aphididae), in both the presence and absence of a lepidopteran caterpillar, Plutella xylostella L. (Lepidoptera: Plutellidae). Female parasitoids chose aphid-infested plants over uninfested plants but did not distinguish
between caterpillar-infested and uninfested plants. When given a choice between odors from an aphid-infested plant and those
from a plant infested with diamondback moth larvae, they significantly chose the former. Furthermore, the parasitoids responded
equally to odors from a plant infested with aphids only and those from a plant infested with both aphids and caterpillars.
The results support the hypothesis that the aphid and the caterpillar induce different changes in the volatile profile of
cabbage plants and that D. rapae females readily distinguish between the two. Furthermore, the changes to the plant volatile profile induced by the caterpillar
damage did not hinder the responses of the parasitoid to aphid-induced signals. 相似文献
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为验证40%氯噻啉水分散粒剂对烟田烟蚜的防治效果,进行了田间药效试验。试验结果表明,40%氯噻啉水分散粒剂对烟蚜有较好的防治效果,药后第10d供试3个剂量的防效为89.83%~96.40%,各处理间无显著性差异。40%氯噻啉水分散粒剂用于防治烟田蚜虫的适宜用量为18.75g/hm2(有效成分),持效期为10d左右。 相似文献
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13.2%敌·溴烟剂防治温室两种蚜虫药效试验 总被引:5,自引:0,他引:5
试验结果表明13.2%敌·溴烟剂对温室棉蚜和桃蚜均有较好的防治效果,适宜用药量分别为90~110ga.i./hm2和110~130ga.i./hm2,持效期均为7天。 相似文献