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THE ANALYSIS AND RECONSTRUCTION OF DIURNAL FLIGHT CURVES IN ALIENICOLAE OF APHIS FABAE SCOP. 总被引:1,自引:0,他引:1
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
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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通过主成分分析法并结合物种的生物学特征对长江上游支流沱江资中段69尾宽体沙鳅Sinibotia reevesae和长江干流宜宾段、南溪段及沱江资中段141尾中华沙鳅Sinibotia superciliaris的10个常规可量性状与20个框架性状进行了比较研究。结果显示: 主成分分析并不能区分宽体沙鳅和中华沙鳅之间的形态差异; 依据二者在尾柄高、吻须长、D1-3(胸鳍基部起点至腹鳍基部起点之间的距离)、D7-9(臀鳍基部后末端至尾鳍基部腹部起点之间的距离)和D9-10(鳍基部腹部起点至尾鳍基部背部起点之间的距离) 等形态特征的显著性差异(P<0.05), 并结合其繁殖生物学特征, 认为中华沙鳅和宽体沙鳅应为2个有效种。建议在使用框架性状度量评价物种有效性时需选择恰当的形态指标, 数据分析应结合物种的生物学特征。 相似文献
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THE IDENTITY OF THE SWEDE MIDGE, WITH NOTES ON ITS BIOLOGY 总被引:1,自引:0,他引:1
A brief historical summary is given of the literature concerning Contarinia nasturtii Kieffer, C. torquens de Meijere and C. geisenheyneri Riibsaamen, three gall midges (Cecidomyidae) which have been associated respectively with leaf damage on Brassica spp. in England, identical malformation on the Continent and swollen and closed flowers of Brassica spp. in Europe.
Following the discovery in England of the true Contarinia nasturtii causing swollen and closed flowers oiRorippa amphibia, preliminary experiments have shown that midges from this source will also cause similar damage to swede flowers and that they are the same species as those attacking R. amphibia blossom in the Netherlands.
Further preliminary experiments have shown that swede midge derived from rape leaf axils will also cause identical damage to radish flowers in addition to breeding successfully on the leaves of turnip, swede, cabbage and radish.
Male midges derived from Rorippa blossom have been mated with females from rape leaf axils, and their offspring have been reared on Rorippa flowers and on turnip leaves.
This biological evidence confirms the previous supposition based on morphological grounds that the swede midge is Contarinia nasturtii Kieffer and will cause either flower or leaf damage. Consequently, C. torquens de Meijere and C. geisenheyneri Riibsaamen must remain synonyms.
The shortest time for a generation (from parent to first offspring midge) to develop was 24–39 days in an unheated open glasshouse during June-July in 1949 at Harpenden. Under the same conditions, the shortest time for the next generation from late July to August was 29–32 days. C. nasturtii is the first Contarinia species in which unisexual families have been discovered. 相似文献
Following the discovery in England of the true Contarinia nasturtii causing swollen and closed flowers oiRorippa amphibia, preliminary experiments have shown that midges from this source will also cause similar damage to swede flowers and that they are the same species as those attacking R. amphibia blossom in the Netherlands.
Further preliminary experiments have shown that swede midge derived from rape leaf axils will also cause identical damage to radish flowers in addition to breeding successfully on the leaves of turnip, swede, cabbage and radish.
Male midges derived from Rorippa blossom have been mated with females from rape leaf axils, and their offspring have been reared on Rorippa flowers and on turnip leaves.
This biological evidence confirms the previous supposition based on morphological grounds that the swede midge is Contarinia nasturtii Kieffer and will cause either flower or leaf damage. Consequently, C. torquens de Meijere and C. geisenheyneri Riibsaamen must remain synonyms.
The shortest time for a generation (from parent to first offspring midge) to develop was 24–39 days in an unheated open glasshouse during June-July in 1949 at Harpenden. Under the same conditions, the shortest time for the next generation from late July to August was 29–32 days. C. nasturtii is the first Contarinia species in which unisexual families have been discovered. 相似文献
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罗布麻属与白麻属叶表面气孔形态的比较观察——兼论Poacynum的归属 总被引:4,自引:0,他引:4
本文报道了罗布麻属和白麻属植物叶表面气孔形态的比较观察。结果表明,两者气孔形态的微观性状十分相似,同属一个类型。结合花部形态的比较分析,认为Poacynum Baill。独立成属的依据是不充分、不合理的,应将之归并回罗布麻属Apocynum L 中。列举了原白麻属所隶下2个种的正确学名。 相似文献
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腔阔盘吸虫尾蚴及后蚴穿刺腺等腺体的组织化学及其功能的初步研究 总被引:2,自引:1,他引:2
本文报道应用组织化学反应方法初步观察了腔阔盘吸虫(Eurytrema coelomaticum)尾蚴及后蚴体中单细胞腺的组织化学成分及其生理功能。尾蚴的5对大单细胞腺主要分泌粘蛋白、酸性粘多糖及微量碱性蛋白质,当子胞蚴被排到外界时,此腺体物质分泌出充满子胞蚴内囊腔并包被着各尾蚴。尾蚴在此腺体分泌物保护下渡过其在外界生存的时间。尾蚴的4对小单细胞腺主要包含中性糖蛋白及结合氨基的蛋白质(可能是含酶物质),此腺体物质可能是在尾蚴进入昆虫宿主(草螽)体内穿钻其胃壁进入血腔时分泌出能溶解胃壁组织帮助尾蚴的穿钻行为。成熟后蚴的穿刺腺对PAS反应呈强阳性,其分泌物可以溶解囊蚴的囊壁,使后蚴迅速脱囊。各幼虫期其他器官组织的组化成分也经观察。 相似文献
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THE BREEDING AND FEEDING OF JACKDAWS AND ROOKS WITH NOTES ON CARRION CROWS AND OTHER CORVIDAE. 总被引:1,自引:0,他引:1
J. D. Lockie 《Ibis》1955,97(2):341-369