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101.
In the tropics the contribution of bees as pollinators of important economic indigenous crops remains largely undocumented. We studied the diversity of bee species visiting indigenous tomato (Solanum lycopersicon) and habanero pepper (Capsicum chinense) in subtropical Yucatán, México. The contribution of two native bees, Exomalopsis (E) and Augochloropsis (AG) was compared with that of the introduced Africanized Apis mellífera (HB) for pollinating unvisited flowers in both crops. Apis mellífera and stingless bees were dominant in habanero pepper but solitary bee species were important visitors of tomato. In spite of both crops being autogamic, there was a significant contribution of native bees for pollination of both tomato and habanero pepper. The comparison of fruit weight, number of seeds, and a pollination index based on the latter showed that E and AG were more effective pollinators compared to HB in both crops (ca. Spear’s index of ca. 0.7 vs. 0.35 respectively). In tomato, a further evaluation of the contribution to pollination provided by the three bee species was made using the rate of visits to flowers. Although E and AG were the most efficient pollinators at single flower visits in tomato, none of the three species (including HB) were able to provide single visits to all flowers per unit time to the crop. Our results underline the importance of maintaining diverse assemblages and abundant populations of bee species that can synergically contribute to the productivity of tomato and hot pepper in the Neotropics.  相似文献   
102.
The year 2010 marks the 175th anniversary of Charles Darwin’s visit to the Galapagos Islands. A recent paper by J. C. Briggs, ‘Darwin’s biogeography’ (Journal of Biogeography, 2009, 36 , 1011–1017), summarizes Darwin’s contributions to the field of biogeography, stressing the importance of his natural history specimens. Here, we illustrate how a plant collected by Darwin during his visit to Floreana and not collected since can provide insights into dispersal to oceanic islands as well as extinction of island plants, based on ancient DNA from Darwin’s herbarium specimen.  相似文献   
103.
Mixed infections of Nicotiana benthamiana plants by Tobacco necrosis virus (TNV) and Turnip crinkle virus (TCV) exhibited an interference interaction. Accumulation of TNV (+)RNA as well as capsid protein in mixed infection were considerably lower than that of singly infected plants. There were also a slight reduction in the levels of TCV (+)RNA and capsid protein in doubly infected plants, which displayed the concentration of both viruses decreased in dually infected plants. Tissue immunoblot analysis of systemic N. benthamiana leaves infected by TNV and TCV singly or doubly showed the interference between the two viruses in situ, which exhibited the decrease of both viruses in doubly infected leaves although the distribution of them did not change remarkably. These results were consistent with the hybridization analysis of viral genomic RNA and coat protein. Both cross‐protection test and mixed infection of the two viruses confirmed TCV had relatively stronger interference to the infection of TNV. Interference infection by TNV and TCV induced higher increase in the levels of cytochrome pathway respiration and alternative pathway respiration in host plants, especially the latter. Interference often occurred in different strains of one kind of virus or two different closely related viruses in one genus. Our results showed that interference could also occur in different viruses belonging to different genera.  相似文献   
104.
105.
We describe the third- and fourth-instar larva, pupa and biology of the hyperparasitoid bee fly Ligyra satyrus (Fabricius). The larval and pupal morphology of the bee fly is typical for members of the subfamily Anthracinae. The bee fly larvae are found inside cocoons of the scoliid Campsomeris tasmaniensis Saussure, an external parasite of canegrubs (Coleoptera: Scarabaeidae) in sugarcane fields at Ayr and Bundaberg, Queensland. Ligyra satyrus has been recorded attacking only C. tasmaniensis . Ligyra and its relatives are all parasites of predatory and parasitic, ground-nesting aculeate Hymenoptera such as Sphecidae, Pompilidae, Tiphiidae and Scoliidae. Larval morphology of the hyperparasite is similar to other ectoparasitic Bombyliidae and pupal morphology is compared to that of species in the same and related subfamilies. Rates of hyperparasitism at Gordonvale reported in the early 1900s are relatively high, but our results show that currently they are very low at Ayr and Bundaberg. These results suggest that the impact of the bee fly on natural control of the canegrubs by scoliids varies considerably.  相似文献   
106.
蜜蜂全基因组出笼前后   总被引:1,自引:0,他引:1  
在2006年10月26日,期待已久的蜜蜂的基因组序列在英国杂志《自然》上发表了。这一事件对于全世界蜜蜂生物学家来说,标志着蜜蜂研究“后基因组时代”的开始。这一重大项目由倍乐医学院完成,耗资800万美元,历时2年。而实际上对于基因组的注释又经过近2年的时间,由代表15个国家、来自64个实验室的170名科学家完成。这一等待是值得的基因组序列最终发表后,生物学家通过互联网能做他们自己的“数据采掘”,用这一可得的公共资源验证自己的假说。事实上,在蜜蜂基因组文章在《自然》上发表的当周,其姊妹刊上发表的约50篇相关论文中,有一半以上是基于生物信息学的研究,这些刊物包括《科学》、《基因组研究》、《美国国家科学院院报》及《昆虫分子生物学》。蜜蜂与人类享有一些共性劳动分工,复杂的通信系统包括语言,发达的保卫和防御系统,精妙的建筑以及为了共同利益自我牺牲的特点。由于有这些共性,蜜蜂基因组的发表将使科学家不仅能够深入研究蜜蜂生物学,而且能深入了解我们人类自身的生物学。  相似文献   
107.
This study aimed to evaluate the performance of hydrogen peroxide vapour (HPV) to inactivate the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine for application in cleaning validation in pharmaceutical industries production areas. Two matrixes were tested: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were dried on stainless steel and exposed to HPV in an isolator. One biological indicator with population >106 Geobacillus stearothermophilus spores was used to validate the HPV decontamination cycle as standard. HPV exposure resulted in complete virus inactivation in FVC (≥5·03 log10) and API (≥6·40 log10), showing HPV efficacy for reducing chimpanzee adenovirus AZD1222 vaccine strain. However, the optimum concentration and contact time will vary depending on the type of application. Future decontamination studies scaling up the process to the recombinant COVID-19 vaccine manufacturing areas are necessary to evaluate if the HPV will have the same or better virucidal effectivity in each specific production area. In conclusion, HPV showed efficacy for reducing AZD1222 chimpanzee adenovirus strain and can be a good choice for pharmaceutical industries facilities disinfection during recombinant COVID-19 vaccine production.  相似文献   
108.
109.
蜜蜂上颚腺及其分泌物研究进展   总被引:1,自引:0,他引:1  
上颚腺是蜜蜂重要的外分泌腺体,其分泌物是维系蜂群社会性结构的重要物质。蜂王和工蜂上颚腺分泌物合成均以硬脂酸为合成前体,但在脂肪酸的β-氧化过程中表现出级型差异性,导致分泌物组分比例不同。蜂王上颚腺分泌物以9-羰基-2癸烯酸(9-ODA)为主,有吸引工蜂和雄蜂、抑制工蜂卵巢发育等作用;工蜂上颚腺分泌物以10-羟基-2癸烯酸(10-HDA)和10-羟基癸酸(10-HDAA)为主,是蜂王浆的重要组成部分。同时,这种具备典型级型差异的分泌物组成又具有级型间可塑性,在不同蜂种间也存在区别。近年来在转录水平和蛋白水平的一些研究进一步揭示了级型间差异的分子基础。针对蜜蜂上颚腺及其分泌物的研究在蜜蜂生物学、行为学和蜂产品质量控制等方面具有重要的意义。本文通过总结国内外相关研究进展,旨在为上颚腺分泌物的作用机制、生物合成机制等领域的进一步深入研究提供借鉴。  相似文献   
110.
As honeybees are the main pollinator subject to an intense research regarding effects of pesticides, other ecologically important native bee pollinators have received little attention in ecotoxicology and risk assessment of pesticides in general, and insecticides in particular, some of which are perceived as reduced‐risk compounds. Here, the impact of three reduced‐risk insecticides – azadirachtin, spinosad and chlorantraniliprole – was assessed in two species of stingless bees, Partamona helleri and Scaptotrigona xanthotrica, which are important native pollinators in Neotropical America. The neonicotinoid imidacloprid was used as a positive control. Spinosad exhibited high oral and contact toxicities in adult workers of both species at the recommended label rates, with median survival times (LT50s) ranging from 1 to 4 h, whereas these estimates were below 15 min for imidacloprid. Azadirachtin and chlorantraniliprole exhibited low toxicity at the recommended label rates, with negligible mortality that did not allow LT50 estimation. Sublethal behavioural assessments of these two insecticides indicated that neither one of them affected the overall group activity of workers of the two species. However, both azadirachtin and chlorantraniliprole impaired individual flight take‐off of P. helleri and S. xanthotrica worker bees, which may compromise foraging activity, potentially leading to reduced colony survival. These findings challenge the common perception of non‐target safety of reduced‐risk insecticides and bioinsecticides, particularly regarding native pollinator species.  相似文献   
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