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31.
不同地理种群大豆蚜生长发育的形态指标 总被引:1,自引:0,他引:1
对采自广东、山东、河北和黑龙江4个省份大豆蚜Aphis glycines Matsumura种群在不同温度条件下的生长发育形态指标进行测定。结果表明,在20、25和30℃,不同地理种群大豆蚜生长发育形态指标差异不显著;在15℃,不同地理种群大豆蚜生长发育形态指标差异显著。在15~30℃,单一大豆蚜地理种群形态指标有随温度降低而增大的趋势。试验结果也表明,单一地理种群大豆蚜的Q值也有随着温度降低而增大的趋势;而在相同温度下,不同种群间的Q值变化不明显,差异性不显著。 相似文献
32.
The parasitoids associated with the common pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer, were investigated at three pistachio plantations in Rafsanjan, Iran. Of the 6504 wasps emerging from mummified psyllids, 46% were the primary parasitoid Psyllaephagus pistaciae Ferrière, and the remaining 54% represented six species of hymenopterous hyperparasitoids, including Chartocerus kurdjumovi (Nikol’skaja), Marietta picta (André), Pachyneuron aphidis (Bouché), Pachyneuron muscarum (Linnaeus), Psyllaphycus diaphorinae (Hayat), and Syrphophagus aphidivorus (Mayr). Lysiphlebus fabarum Marshall, the parasitoid of Aphis gossypii Glover and Aphis craccivora Koch present on weeds, was found to be an alternative host for three major hyperparasitoids of A. pistaciae. The most abundant hyperparasitoid was S. aphidivorus, appearing during the growing season in all trial locations on psyllids and aphids in pistachio orchards. The weed-infesting aphids, along with their primary parasitoid, can act as a reservoir of A. pistaciae secondary parasitoids. Therefore, parasitized aphids allow populations of secondary parasitoids to increase and consequently to apply higher pressure on P. pistaciae. We detected that two primary parasitoid species, including P. pistaciae and L. fabarum, attacking different species of hosts interact indirectly through shared secondary parasitism. It is suggested that the community structure of A. pistaciae may be influenced by apparent competition, although more work is needed to provide firm evidence. 相似文献
33.
大豆蚜的生物学防治技术 总被引:1,自引:0,他引:1
大豆蚜AphisglycinesMatsumura是亚洲大豆种植区的一种主要农业害虫。近年来,大豆蚜又先后侵入北美洲和大洋州等地,对当地的大豆生产构成了潜在威胁,正成为一种世界性的农业害虫。文章对大豆蚜的分布、危害、生物学特征、天敌和防治技术等方面的研究现状进行了详细论述。 相似文献
34.
There has been much debate regarding the impact of parasitoid competition and hyperparasitism on the successful biological control of aphid pests. Difficulty in the evaluation of interspecific interactions and trophic links using conventional rearing and dissection methods has prevented a deeper understanding of such relationships. The analysis of trophic links in the parasitoid community associated with the melon aphid (Aphis gossypii) in Hawaii provides a unique opportunity to assess complex interactions that occur in a system where all of the aphids and parasitoids have been introduced. Here, we developed and applied multiplex PCR assays to investigate the occurrence of in-host competition between parasitoids and/or hyperparasitoids on melon aphids collected from fields of Colocasia esculenta. To fully document the parasitoid-hyperparasitoid community within A. gossypii, both live and mummified aphids were examined. A total of 818 live and 245 mummified aphids were analyzed using the multiplex assays, with congruent rearing of over 600 mummified aphids serving as a basis for qualitative comparisons in terms of species composition and trophic linkages. The rearing and the DNA methods showed similar trends, with sharp declines in one parasitoid species followed by sharp increases in another during the course of the season. Molecular analyses revealed that hyperparasitism and multiparasitism of live aphids is remarkably low, whereas hyperparasitism of mummified aphids was extraordinarily high in both rearing and molecular analyses. In comparison to reared samples, molecular analysis of the parasitoid community was more complete and permitted the identification of previously unknown or unconfirmed trophic linkages. The potential of this approach in future studies on the biological control of aphids in Hawaii, particularly in light of new parasitoid introductions, is discussed. 相似文献
35.
Daniela T. Pezzini 《Biocontrol Science and Technology》2015,25(9):1024-1035
The invasive soybean aphid, Aphis glycines Matsumura, is an important pest in North American soybean production. Predators can play an important role in suppressing A. glycines. However, current A. glycines management practices rely primarily on broad-spectrum insecticides, which can adversely affect natural enemy populations. An alternative is the use of selective insecticides that control the targeted pest species, while having a reduced impact on natural enemies. In greenhouse and laboratory assays, we tested the effects of lambda-cyhalothrin, two rates of flonicamid, which is currently not registered for use in soybean, and a formulated mixture of pyrthrins and azadirachtin on A. glycines and its natural enemies, Chrysoperla rufilabris (Burmeister), Orius insidiosus (Say) and Hippodamia convergens (Guerin-Meneville). All insecticides significantly reduced A. glycines populations. Lambda-cyhalothrin was highly toxic to the natural enemies tested. Flonicamid showed the lowest toxicity to natural enemies, but the high rate did decrease survival of O. insidiosus. The mixture of pyrethrins and azadirachtin was toxic to larvae of C. rufilabris and adult O. insidiosus. Moreover, the mixture of pyrethrins and azadirachtin increased the developmental time of C. rufilabris. These results indicate potential for flonicamid and the mixture of pyrethrins and azadirachtin to increase compatibility between chemical and biological controls. 相似文献
36.
Md Ruhul Amin Mohsen Ara Sharmin Md Ramiz Uddin Miah Abdul Mannan Akanda Sang Jae Suh Yong Jung Kwon Ohseok Kwon 《Entomological Research》2020,50(6):257-266
The population abundance, infestation, and harmful effects of the aphid Aphis craccivora Koch (Hemiptera: Aphididae) were studied on four bean plant species, namely the country bean (Lablab purpureus var. BARI Seem 1), the yard‐long bean (Vigna sesquipedalis var. BARI Borboti 1), the hyacinth bean (Dolichos lablab var. BARI Seem 6), and the bush bean (Phaseolus vulgaris var. BARI Jar Seem 3). Aphid abundance and infestation on the leaves, inflorescences, flowers, and pods differed significantly among the bean plant species, with P. vulgaris and V. sesquipedalis having the lowest and highest results, respectively. Aphid severity grade and the number of trichomes of the bean plant species were negatively correlated. The duration of the growth stages among the bean plant species were significantly different, with V. sesquipedalis having the shortest durations. Aphid abundance and infestation significantly affected the physical and phytochemical characteristics of the bean plant species. The highest reduction of number of leaves, flower inflorescences, and pod inflorescences per plant, and moisture and chlorophyll content in the leaves was found in L. purpureus. The results for V. sesquipedalis revealed the highest reduction in plant height, seed weight, and pH, while those of D. lablab showed the highest reduction in leaf area. 相似文献
37.
M. J. van Steenis K. A. M. H. El-Khawass 《Entomologia Experimentalis et Applicata》1995,76(2):121-131
Life table data forAphis gossypii Glover (Homoptera: Aphididae), an important pest in glasshouse cucumber crops, were studied at 20, 25 and 30°C on two cucumber
cultivars (Cucumis sativus L.) in controlled climate cabinets. The development time on the cucumber cv. ‘Sporu’ ranged from 4.8 days at 20°C to 3.2
days at 30°C. Immature mortality was approximately 20% and did not differ between temperatures. Most mortality occurred during
the first instar. Reproduction periods did not differ among temperatures, but at 25 and 30°C more nymphs were produced (65.9
and 69.8 nymphs/♀, respectively) than at 20°C (59,9 nymphs/♀) because of a higher daily reproduction. Intrinsic rate of increase
was greatest at 25°C (r
m
=0.556 day−1). At 20 and 30°C the intrinsic rate of increase was 0.426 and 0.510, respectively. On cv. ‘Aramon’, the development time
ofA. gossypii was approximately 20% longer at all temperatures. Immature mortality did not differ between the two cultivars. The intrinsic
rate of increase on cv. ‘Aramon’ was 15% smaller than on cv. ‘Sporu’. The use of cucumber cultivars partially resistant to
aphids is discussed in relation to biological control of cotton aphid in glasshouses. Development time and immature mortality
on leaves of the middle and upper leaf layer of glasshouse grown cucumber plants (cv. ‘Aramon’) were comparable to development
in the controlled climate cabinets. On the lower leaves immature mortality was much higher (approximately 82%) than on leaves
of the middle (24.0%) and upper leaf layer (24.5%). Reproduction was less on the lower leaf layer (45.9, 70.5 and 70.1 nymphs/♀
on leaves of the lower, middle and upper leaf layer, respectively).
Aphids, successfully parasitized byAphidius colemani Viereck (Hymenoptera: Braconidae) only reproduced when they were parasitized after the third instar. Fecundity was 0.1 to
0.9 and 10.5 to 13.3 nymphs/♀ for aphids parasitized in the fourth instar or as adults, respectively. Reproduction of aphids
that were stung but survived the attack was lower than for aphids not stung. Average longevity of these aphids was equal to
the longevity of aphids not stung byA. colemani. 相似文献
38.
大豆蚜嗅觉在选择寄主植物中的作用 总被引:14,自引:1,他引:14
大豆蚜 Aphis hlycines 有翅和无翅孤雌生殖蚜为其寄主植物大豆叶和鼠李叶气味所引诱,而非寄主植物棉花叶和黄瓜叶气味处于中性,丝瓜叶和南瓜叶气味具有明显的排斥作用。非寄主植物气味可以遮蔽寄主植物气味的引诱作用。大豆蚜触角感受器对植物气味具有嗅觉生理反应,对一些化合物的最小感觉阈值达10-5至10-6体积比浓度,表明大豆蚜触角上存在识别植物气味的嗅觉受体细胞。由此证明,嗅觉在大豆蚜选择寄主植物过程中起重要作用。 相似文献
39.
一种黑豆蚜储存蛋白质的分离纯化及其亚基的性质 总被引:1,自引:0,他引:1
从黑豆蚜 (AphiscraccivoraKoch)血淋巴中经DE5 2纤维素离子交换层析、SephadexG 15 0凝胶过滤以及在FPLC上QSepharose分离出一种蛋白质。该蛋白质经SDS PAGE测定在非还原和还原条件下分子量均为 6 0kD左右 ,等电聚焦电泳测得其等电点约为 5 .0 ,为糖蛋白。若蚜期间该蛋白质在蚜虫体内积累 ,羽化至成蚜时含量明显减少 ,为蚜虫提供发育所需氨基酸 ,在成蚜期间仍以低浓度存在。根据其分子量和氨基酸组成与含量变化动态应属不完全变态昆虫的一种持续性储存蛋白质。 相似文献
40.
J. P. Michaud 《Biological Control》2000,18(3):287
Seven species of Coccinellidae inhabiting citrus groves in Florida were evaluated for ability to develop and reproduce on the citrus aphids Toxoptera citricida (Kirkaldy) and Aphis spiraecola Patch. Choice tests performed with adults and larvae indicated that both aphid species were generally acceptable prey. Coccinella septempunctata L., Coleomegilla maculata fuscilabris (Mulsant), Coelophora inaequalis F., and Olla v-nigrum Mulsant were unable to complete development on either aphid. Hippodamia convergens Guerin larvae completed development on A. spiraecola with 68% survival; none survived on T. citricida. Only Cycloneda sanguinea (L.) and Harmonia axyridis Pallas completed development on both A. spiraecola (60 and 70% survival, respectively) and T. citricida (100 and 95% survival, respectively). Larval developmental time was shorter on T. citricida than on A. spiraecola, and resulting adults were heavier, differences being more pronounced in H. axyridis. Females of C. septempunctata, C. inaequalis, and O. v-nigrum produced viable eggs on T. citricida. O. v-nigrum did not produce eggs on A. spiraecola. Females of C. m. fuscilabris and H. axyridis produced no eggs on A. spiraecola and mostly infertile eggs on T. citricida. Female H. convergens laid twice as many eggs feeding on T. citricida as on A. spiraecola and egg viability was similar. C. sanguinea females laid similar numbers of eggs on both aphids, but eggs produced on A. spiraecola had higher fertility. Pollen added to the T. citricida diet temporarily improved the fertility of H. axyridis females, but not that of C. sanguinea females. C. sanguinea was judged the best candidate for augmentative biocontrol of T. citricida, the primary vector of citrus tristeza virus. 相似文献