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Li-Fang Gao Yu-Jie Wang Hai-Yang Zhang Wen Zhang Xiao-Dan Zhang Zhen-Qin Zhu Bo Du 《Ecological Entomology》2020,45(5):978-987
- The coevolution of insect pollinators and their host plants is a typical example of natural selection; however, how insect pollinators avoid overdependence on one peculiar plant remains unclear. As most insect pollinators exhibit a diet breadth when showing flower constancy, determining the difference and similarity of most and less preferred flowers by insect pollinators may be helpful to understand their trade-off between flower constancy and overdependence.
- This was addressed using the long-proboscid tangle-veined fly (Nemetrinus spp.). Dietary investigation indicates that the flies show constancy for the morphological characteristic of the Delphinium caeruleum, which is the most preferred plant for this Nemestrinidae fly that has blue, long-tubed flowers.
- In a colour selection experiment, focal individuals showed obvious preference for white, which is the colour of less preferred flowers by the fly in the natural environment. In a scent selection experiment, focal individuals showed obvious preference for D. caeruleum and Dracocephalum heterophyllum but avoidance to Dasiphora fruticosa and Dasiphora davurica. This indicates that long-proboscid tangle-veined flies can forage on other flowers, despite the existing constancy for D. caeruleum, as long as they do not hate the scent. It seems that long-proboscid tangle-veined flies can maximise foraging efficiency by showing constancy for the morphological characteristic of the most preferred plant and for the scent and colour of less-preferred plants.
- The trade-off of long-proboscid tangle-veined flies in the selection of nectar sources may be an adaptation to the risk of overdependence on one plant in evolution.
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Reactions of the β-diketiminate lithium salt L2Li [L2={(2,6-Me2C6H3)NC(Me)}2CH] with anhydrous LnCl3 (Ln=Yb, Sm, Nd) in 1:1 molar ratio in THF afforded the new β-diketiminate lanthanide complexes L2LnCl(THF)(μ-Cl)2Li(THF)2 (Ln=Yb (1), Sm (2), Nd (3)). Recrystallization of complexes 1-3 from toluene gave the neutral complexes L2LnCl2(THF)2 (Ln=Yb (4), Sm (5), Nd (6)). Recrystallization of complexes 4 and 5 in hot toluene for two times gave the dinuclear complexes L2ClLn(μ-Cl)3LnL2(THF) (Ln=Yb (7), Sm (8)). Treatment of the mother liquor of complex 2 in hot toluene for three times gave the novel trinuclear complex L2SmCl(μ-Cl)3SmL2(μ-Cl)Li(L2H)(THF) (9). Each of these complexes was well characterized, while complexes 3, 7 and 9 have been characterized by X-ray diffraction structure determination. 相似文献
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F3-PE40基因的克隆、表达及纯化 总被引:1,自引:0,他引:1
通过质粒提取、PCR扩增构建F3-PE40表达载体转化大肠杆菌,然后进行表达纯化。以pEKH-F3质粒为模板,PCR扩增F3片段,将F3插入克隆质粒PQE80L,转化大肠杆菌,筛选获得含有F3的PQE80L重组载体。提取绿脓杆菌菌株染色体DNA为模板,PCR扩增绿脓杆菌外毒素A催化区(PE40)。然后将PQE80-F3和PE40重组,得到表达PQE80L-F3-PE40载体。转化至大肠杆菌DH5a,BL21,表达融合蛋白F3-PE40。大肠杆菌表达了融合蛋白F3-PE40,表达的融合蛋白量占菌体总体蛋白量的20%。成功地表达了融合蛋白F3-PE40,为进一步大规模表达、纯化F3-PE40功能奠定了基础。 相似文献
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稻虱缨小蜂的寄主选择性和适宜性 总被引:6,自引:4,他引:6
稻虱缨小蜂Anagrus nilaparvatae Pang &Wang对白背飞虱Sogatella furcifera(HO· rvath)卵龄无明显的寄生选择性,但在新鲜寄主中的发育历期较短,育出的蜂体较大,生殖力较高,而羽化 率和雌雄性比则不受寄主卵龄的影响。在白背飞虱和褐飞虱Nilaparvata lugens (Stal)卵共存时,稻虱缨小蜂明显选择褐飞虱。稻虱缨小蜂在褐飞虱卵中的发育显著地比在白背飞虱卵中的慢;褐飞虱卵育出的 蜂的初羽化成虫怀卵量显著高于白背飞虱卯育出的,虫体大小也类似,且虫体越大,生殖力越高。从白背飞虱卵育出的蜂供给白背飞虱卵(W→W)时,产卵量低于其它育蜂寄主和供给产卵寄主组合(w→B、B→B、B→W)的,其内禀增长力rm较其余者小25%。本文还讨论了应用适宜性指数来综合衡量寄主的适宜性。 相似文献
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Sexual conflict in producing and raising offspring is a critical issue in evolutionary ecology research.Individual experience affects their breeding performance,as measured by such traits of provisioning of offspring and engagement in extra-pair copulations,and may cause an imbalance in sexual conflict.Thus,divorce is hypothesized to occur within aged social pairs,irrespective of current reproductive success.This concept was explored in the azure-winged magpie Cyanopica cyanus by investigating the divorce of a social pair and its relationship to their changes in breeding performance with prior experience.Females engaging in extra-pair copulation may intensify sexual conflicts and may be the main reason for divorce.Once divorced,females repairing with an inexperienced male realized higher reproductive success than that repairing with an experienced male;males repairing with an experienced female realized higher reproductive success than that repairing with an inexperienced female.This finding indicates that the fitness consequence of divorce depends on the breeding experience of new mates.Divorced females can obtain more extra-pair copulations,whereas divorced males cannot,when they repair with inexperienced breeders.Divorced females provisioned a brood at lower rates than inexperienced females whereas divorced males had no such difference.It appears that divorced females can obtain an advantage in sexual conflicts with inexperienced mates in future reproduction.Consequently,females are probably more active than males in divorcing their aged mates so as to select an inexperienced male as a new mate.Azure-winged magpies thus provide novel insights into the implicaticns of sexual conflict in birds. 相似文献
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在本实验室研制出的多株针对H5N1亚型禽流感血凝素单抗中,13D4单抗对所有H5亚型病毒均有血凝抑制和中和活性,具有特异性高、反应性强和识别广的特点,且在小鼠实验中显示了对各种代表株禽流感的感染和发病均具有良好的治疗效果。在此研究基础上,本实验通过基因工程构建含有13D4单链抗体(scFv)基因的毕赤酵母表达载体,实现目的蛋白的分泌性表达和纯化。经过竞争法和血凝抑制检测其活性,表明获得的单链抗体具有与原始鼠源抗体相近的反应活性和相同的识别表位。H5N1广谱中和单抗13D4的单链抗体的成功构建,为进一步研制针对H5N1禽流感病毒的治疗性抗体奠定了基础。 相似文献
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