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Experiments, in which alate aphids were marked immediately after eclosion from the last nymphal instar and observed until they took flight, gave information which, together with the measured rate of moulting and a continuous record of temperature, has been used to construct theoretical daily curves for numbers flying from a bean crop. These curves have been matched against the observed curves for the same days.
The differences between curves so constructed for a period of 17 days and the observed curves for the same period are of the same order and kind as the differences between two measured curves in different sites at the same time.
The different types of daily flight curve can thus be accounted for in terms of the rate of production of alatae by moulting, the effect of temperature on the teneral ('drying out') period and the effect of low light intensity and temperature on take-off behaviour.  相似文献   

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萝卜蚜和豆蚜染色体C-带带型比较与分析   总被引:3,自引:1,他引:2  
本研究利用C-带技术,显示出萝卜蚜和豆蚜的染色体C-带带型,并进行了初步分析。萝卜蚜与豆蚜的染色体在组型上只有第4对染色体稍有区别;在带型上两者有很明显的差异。萝卜蚜有2对散漫着丝粒染色体,豆蚜没有该种染色体。豆蚜的第4对染色体在端部缺少-C带带纹。萝卜蚜的第2对染色体与豆蚜的第2对染色体带型相似。根据萝卜蚜和豆蚜的C-带带型,讨论了二者在进化中的亲缘关系。  相似文献   

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Bean fields are often attacked by Aphis fabae very heavily along the edges: and on a field at Rothamsted in 1948 the sides facing the wind during the primary migration had more colonies than those in the lee of the crop (Johnson, 1950). Additional observations on the distribution of colonies were made on six bean fields at Sutton Bonington in 1950–2.
At Rothamsted in 1948 it was assumed that the more numerous colonies on the windward sides of the field followed a heavier deposition of primary migrants there, though the migrants themselves were not observed on the crop. In 1950–2 the locations of primary migrants, as well as of colonies, were recorded in three out of the six fields observed.  相似文献   

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棉蚜对“1059”抗药性的测定   总被引:10,自引:4,他引:6  
一、前言 近十年来,各种农业害虫对杀虫剂的抗药性,已陆续被发现。其中关于蚜虫的抗药性,虽然亦有记述,但增加抗药性的倍数不多,并不发展得很严重。例如,Michelbacher(1954)曾报导,核桃蚜(Chramaphis juglandicola Kltb.)对1605的抗性为7倍;Knipling(1954)报导,红薯蚜(Macrosiphum solanifolii Ashm.)对 DDT及1605有抗性; Anthron(1955)报导,桃绿蚜(Myzus persicae Sulzer)对1605有抗性,但用1059防治,效果仍很好;Stern(1958)报导,苜蓿斑蚜(Therioaphis maculata Buckton)对1605的抗性约4倍。  相似文献   

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A method is described for producing some hundreds of apterous and thousands of alate virginoparous Aphis fabae every day continuously throughout the year. Broad beans are used as the host plants, in a 'production-line' arrangement of eleven ventilated breeding cages, with additional cages for starting subcultures and rearing alatae, all contained in a portion of a small greenhouse with supplementary lighting in winter. When running smoothly, the culture requires about half an hour's work by one man per day.
An 'aphid gun', being a modified type of aspirator catcher, is described, with which large numbers of aphids could be handled and counted rapidly without damaging them.
Amodified technique for host-transference experiments is described, which permits individual leaves to be compared one with another as host-units for the aphids. Two types of small metal cages are used, both easily attached to leaves in their natural positions on growing plants. One type confines the aphids to a part of a single leaf and is used mainly for determining relative reproduction rates on different leaves. The other type encloses equal areas of two different leaves between which the aphids can move freely, and is used for determining their behavioural preferences. The principles underlying the use of such cages, the experimental procedures and the interpretation of the results obtained are discussed.  相似文献   

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R. Charles Long 《Ostrich》2013,84(3):85-104
Coppinger, M. P., Williams, G. D. &; Maclean, G. L. 1988. Distribution and breeding biology of the African Skimmer on the Upper and Middle Zambezi River. Ostrich 59: 85–96.

Observations were made on the distribution and breeding biology of the African Skimmer Rynchops flavirostris from May to November 1986 and April to December 1987, along 1550 km of the Zambezi River from its source to the Luangwa-Zambezi confluence at the Mozambique border. The 280-km Angolan section was omitted. Bird habitats along the river were mapped and the distribution of the African Skimmer was compared with the availability of its breeding habitat. 35 breeding colonies were found of which 33 were on the Barotse floodplain. Eggs were noted during August, September and October; they were laid in scrapes on bare sand in clutches of mostly 2–3. 260 eggs were measured from 101 clutches (a 39,6 x 28,4 mm). Both parents incubated and cared for the young. In hot weather, adults drank often and belly-wetted at nest relief. Chicks stayed in the nest for two days and were almost constantly shaded by the parents. Distraction displays by the adults were observed. The Upper and Middle Zambezi African Skimmer population was estimated to be 1428 birds. The important breeding areas were noted and possible threats to their conservation are discussed.  相似文献   

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秦永杰   《广西植物》1985,(2):141-145
<正> 五倍子,即由半翅目蚜科(Aphididae)的角倍蚜寄生在盐肤木(Rhus chinensis Mill.)上,危害叶组织所造成的一种病理产物——虫瘿的总称。五倍子主要成分为单宁酸,是医药,化工、印染和国防上的重要原料。目前,我国的五倍子按外形可分为十余种,其中以角倍蚜分布最广,产量最高。角倍蚜亦称五倍蚜(Schlechtendalia chinensis Bell),一年有六个世代,终年生活,无休眠阶段。成虫有有翅型及无翅型两种,当盐肤木快落叶之  相似文献   

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龟纹瓢虫对豆蚜的捕食功能反应及寻找效应研究   总被引:10,自引:0,他引:10  
龟纹瓢虫雌虫和雄虫对豆蚜的功能反应符台Holling Ⅱ型模型,其模型为:Na=0.9233N/(1 0.0171N)(雌虫)和Na=0.8641N/(1 0.0164N)(雄虫),瓢虫捕食豆蚜的数量随豆蚜密度增加而增加.但寻找效应随豆蚜密度增加而降低。日最大捕食量和最佳寻找密度分别为37.42(雌)、34.11头(雄)和17.25(雌)、15.8头(雄)。龟纹瓢虫寻找效应随自身密度的增加而降低,其数学模型为:E=0.3032·P^-15634(雌)和E=0.3048·P^-1.1697(雄)。干扰反应的教学模型为:E=0.8104·P^-2.1721(雌),E=0.7125·P^-2.2660,E=0.5963·P^-2.1751(雌雄混台种群)。  相似文献   

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应用灰色系统理论探讨瓢虫的迁飞和蚜虫的防治   总被引:1,自引:0,他引:1  
于秀林  任朝佐 《生态学报》1989,9(2):163-166
在多年的探索中蔡晓明等人首次提出了中国七星瓢虫迁飞的假设,不仅从理论上做了论证,而且与实际现象相当符合。在一定的地面和高空的气象条件下就有迁飞的瓢虫出现,因此,在北方考虑蚜虫的防治时应当考虑瓢虫迁飞的因素,利用迁飞而来的瓢虫去防治蚜虫。由于有些因子之间的关系是灰色的,所以本文应用灰色系统理论做了探讨。从所得结论可看出用灰色系统理论探讨瓢虫迁飞与蚜虫防治的相互关系与人们的感性认识是一致的。  相似文献   

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