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1.
Thirty years of plant transformation technology development   总被引:1,自引:0,他引:1  
Technology development is seminal to many aspects of basic and applied plant transgenic science. Through the development and commercialization of genetically modified crops, the evolution of plant transgenic technologies is also relevant to society as a whole. In this study, literature statistics were used to uncover trends in the development of these technologies. Publication volume and impact (citation) over the past 30 years were analysed with respect to economic zones, countries, species and DNA delivery method. This revealed that, following a dramatic expansion in the 1980s, publications focusing on the development of transgenic technology have been slowing down worldwide since the early mid-1990s, except in a few leading Asian countries. The implications of these trends on the future of plant transgenic science as a whole are discussed.  相似文献   

2.
Main vistas of Academician M.Kh. Chailakhyan's inquiry into the problems of plant growth and development are reviewed with the emphasis on the input of his research in elucidating the mechanisms of flowering, tuberization, sex expression, and the integrity of plant organism. The pioneer studies conducted by Chailakhyan and his colleagues on agricultural applications of phytohormones, their synthetic analogs, and other growth regulators are considered. Highlighted is the role of theoretical papers written by Chailakhyan, his lectures, and his brave fight against pseudoscientific trends in the Russian science is stressed.  相似文献   

3.
Flemish greenhouse growers predominantly use handheld spray guns and spray lances for their crop protection purposes although these techniques are known for their heavy workload and their high operator exposure risks. Moreover, when these techniques are compared with spray boom equipment, they are often found to be less effective. On the other hand, handheld spraying techniques are less expensive and more flexible to use. Additionally, many Flemish growers are convinced that a high spray volume and spray pressure is needed to assure a good plant protection. The aim of this work was to evaluate and compare the spray deposition, penetration and uniformity between a manually pulled horizontal spray boom and a spray gun under controlled laboratory conditions. In total, six different spray application techniques were evaluated. In general, the total deposition results were comparable between the spray boom and the spray gun applications but the boom applications resulted in a more uniform spray distribution over the crop. On a plant level, the spray distribution was not uniform for the different techniques with highest deposits on the upper side of the top leaves. Using spray guns at a higher spray pressure did not improve spray penetration and deposition on the bottom side of the leaves. From the different nozzle types, the XR 80 03 gave the best results. Plant density clearly affected crop penetration and deposition on the bottom side of the leaves.  相似文献   

4.
2014年中国植物科学若干领域重要研究进展   总被引:2,自引:3,他引:2  
2014年中国植物科学高速稳步发展,表现在具有原创意义的高质量论文迅速增长。中国科学家在植物学诸多领域,如水稻(Oryza sativa)独脚金内酯信号转导途径、水稻代谢遗传调控、水稻育性的遗传调控机理及农业与环境生物学等取得了大量重要成果,基因组研究从功能到进化、从模式作物扩散到各类经济作物,表现出全方位多维度的整合研究态势。全球气候变化下碳汇响应机制取得重要进展。Nature等国际学术刊物高度关注中国植物科学特别是水稻生物学研究进展。该文概括性综述了2014年中国本土植物科学若干领域取得的重要研究进展,旨在全面追踪当前中国植物科学领域发展的最新前沿和热点事件,并与国内读者分享我国科学家所取得的杰出成就。  相似文献   

5.
2015年中国植物科学若干领域重要研究进展   总被引:3,自引:2,他引:1  
2015年中国植物科学研究处于飞速发展的态势, 主要表现在中国植物生命科学家在国际顶级学术刊物发表文章的数量呈现出明显的优势。中国科学家在植物学诸多领域取得了骄人的成果, 如高等植物PSI与捕光天线的超分子复合物晶体结构的解析、水稻感知和耐受寒害机制、乙烯信号转导分子机制研究等。2015年中国生命科学领域十大进展中, 植物科学领域有两项成果入选。值得一提的是, 中国本土科学家因青蒿素的发现与抗疟疾药物新疗法的开创首次获得自然科学领域的诺贝尔奖, 标志着中国植物化学和中药学对人类健康事业的巨大贡献受到国际高度关注, 也标志着中国科学家围绕国家重大需求开展科学技术问题研究模式的有效性和影响力。中国植物科学从跟踪、并行, 逐渐迈入领跑学科发展的方阵。该文对2015年中国本土植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪当前中国植物科学领域发展的最新前沿和热点事件, 并与国内读者分享我国科学家所取得的杰出成就。  相似文献   

6.
Recent analyses of internet search volume hypothesized a decline of public interest toward themes related to environment, biodiversity conservation and fishery. These analyses were based on Google Trends, which is a measure of how frequently a term is searched in Google, in proportion to the total of searches performed. Google Trends is a measure of relative search, and this may make difficult assessing temporal trends. I evaluated whether relative declines in internet search volumes represent genuine decline in interest toward environmental-related themes, by comparing trends of terms representing various themes, including environment, computer science, other disciplines (astrophysics) and leisure. Similar values of relative decline were detected for environmental terms, for computer science terms, and for other scientific disciplines. Conversely, an increase was observed for leisure related terms. This suggests that interest toward the environment is not truly decreasing. The apparent decline of environmental and scientific terms is most likely caused by the increasing use of internet for aims unrelated to science and technology, such as leisure. Internet search tools are a powerful source of information, but users should be aware of the complexity of analysing their data: using unrelated terms as benchmark may help to identify genuine trends.  相似文献   

7.
Classification of vegetation: Past,present and future   总被引:1,自引:0,他引:1  
Abstract. This paper is a report on the past, status-quo and perspectives of vegetation classification, still a major occupation of many vegetation scientists. The history of vegetation classification is discussed against a background of several controversial issues such as the problem of continuum vs. discontinuum, naturalness vs. arbitrariness of the nature of plant communities, universality vs. ad hoc character of syntaxonomic schemes, as well as classical versus numerical approaches to data analysis for classification purposes. The development of the methodology of vegetation science and the present image of vegetation classification is documented by a bibliometric analysis of the publication record of four majorjournals: Journal of Vegetation Science, Vegetatio, Phytocoenologia and Tuexenia. This analysis revealed a persisting controversy between traditional and numerical approaches to vegetation classification. A series of important changes in vegetation science (foundation of new journals, change of editorial policy by the established, important meetings) punctuate a period called the ‘Innovation period’. Several trends in the development of methods of vegetation systematics are summarized under the headings formalism, pluralism, functionalism, pragmatism and indeterminism. Some new features, such as the development and improvement of numerical tools, use of large data banks and attempts to summarize the theory of vegetation classification are discussed. The new growth-form system of Barkman initiated a revival of physiognomy-based vegetation classification. Within this framework the use of the character-type concept and the development of new numerical methods for studying the hierarchical structure of character-set types seems to be a promising approach. The achievements of population biology and ecophysiology have affected vegetation science by emphasizing the functionality of species within plant communities. The use of guilds and other functional groups has experienced an increasing interest from vegetation scientists. Applied in vegetation science, fuzzy-set theory has bridged the techniques of classification and ordination of plant communities.  相似文献   

8.
关于植物营养生态学   总被引:7,自引:0,他引:7  
植物营养学与植物生态学发展的前沿交叉正形成了植物营养生态学,植物营养生态学是探讨植物营养利用策略的科学,包括植物体内营养的合理利用策略和植物对无机营养环境的改造以利于营养吸收的各种可能策略。其研究内容主要包括养分利用效率、植物体内营养的再利用、体内营养含量格局和植物对土壤无机营养环境的改造。植物营养生态学以植物种群为研究对象。它的发展对深刻理解种群的生态行为特征具有重要意义,同时对如何增进人工混交群落的营养协调性具有实践上的指导意义。营养生态机理的各个方面是相互协调和相互补充的整体,营养生态机理的效率决定了种群营养合理利用的程度和在营养资源上的竞争力。目前,研究上尚缺少营养策略与其它生态策略的关联性的探讨,随着各种营养策略研究上的深入,这种关联性探讨将成为今后植物营养生态学的主要发展趋势。  相似文献   

9.
This paper examines the broad movements of Canadian period and cohort fertility over the past 100 years, and compares them with corresponding trends in the US and other industrialized countries. The main movement in Canada was a decline in fertility extending from the 19th century to the present, interrupted in the 1940s and 1950s by a baby boom. Between 1871 and 1937 the total fertility rate (TFR) fell at about an average of 1.4% annually. The rate of fall in the US was similar, with the result that in the late 1930s the Canadian TFR was about 20% that of the US. The fertility boom that followed was steeper in the US than in Canada, and in the downswing that later followed, the rate of decline was similar in the 2 countries (3.4-4% annual average). But, the decline continued longer-- indeed still continues--in Canada, whereas the TFR in the US reached its lowest point in 1976. Moreover, the recent decline in fertility has been more severe in Canada than in almost any other industrialized country. The TFR relates to fertility in a single year and is highly sensitive to short-term changes in the timing of births. For the purposes of understanding and explaining long-term trends in fertility, the completed fertility rate (CFR) is a better index because it measures the ultimate family size of cohorts. Cohort fertility can be seen to fluctuate much less than does period fertility. In both the US and Canada, the peak cohorts, born in the early 1930s, had roughly the same completed fertility, and later cohorts continued to remain closely in step as the CFR fell sharply. In Canada the fall continues, though at a reduced rate, in the latest cohorts for which there is information. Apart from differences in amplitude, the dates of turning points and the shapes of the TFR and CFR curves of Canadian fertility are fairly similar. The long decline in cohort fertility is largely explained by the decrease in the proportions of families of 6 or more children. During the baby boom, for Catholics and non-Catholics alike, the proportion of ever-married women remaining childless fell by about 40%, the proportion having 2 children changed little, and the proportions having 3,4 and 5 children tended to increase substantially. The crucial difference between the 2 groups was in the proportions of women having 6 or more children. For non-Catholics, the proportion fell by over 4% from a high level. For non-Catholics, on the other hand, the proportion rose somewhat, though even after the rise, it was barely more than 1/2 the level to which the Catholic proportion had declined. Among Catholics, the effect of the massive decline in the proportion of women having 6 or more children was to swamp the effects of the increase in the proportions of women having 3, 4 and 5 children. The net effect was that fertility declined. Among non-Catholics, however, the comparable increases in the proportions of families of 3, 4 and 5 children, were not offset by any fall in the proportion of larger families, with the result that a baby boom occurred.  相似文献   

10.
Levesley A  Jopson J  Knight C 《The Plant cell》2012,24(4):1306-1315
We provide evidence from a 5-year study to show that a single concerted effort at the start of undergraduate study can have a clear and lasting effect on the attitudes of students toward plant science. Attendance at a week-long residential plant science summer school in the first year of an undergraduate degree resulted in many students changing courses to include more plant science and increased numbers of graduates selecting plant-based PhDs. The evidence shows that the Gatsby Plant Science Summer School has increased the pool of high-quality plant science related PhD applicants in the UK and has had a positive impact on students' career aspirations. The results are discussed within the context of enhancing the pipeline of future plant scientists and reversing the decline of this vulnerable and strategically important subject relevant to addressing food security and other major global challenges. We have shown that a single well-designed and timely intervention can influence future student behavior and as such offers a framework of potential use to other vulnerable disciplines.  相似文献   

11.
As public and political debates often demonstrate, a substantial disjoint can exist between the findings of science and the impact it has on the public. Using climate-change science as a case example, we reconsider the role of scientists in the information-dissemination process, our hypothesis being that important keywords used in climate science follow “boom and bust” fashion cycles in public usage. Representing this public usage through extraordinary new data on word frequencies in books published up to the year 2008, we show that a classic two-parameter social-diffusion model closely fits the comings and goings of many keywords over generational or longer time scales. We suggest that the fashions of word usage contributes an empirical, possibly regular, correlate to the impact of climate science on society.  相似文献   

12.
全基因组序列测定为揭示植物重要性状形成的分子和遗传机制提供了强大工具,基因组学研究正开始指引着农作物新品种培育向定向化和精确化转变.在新一代测序技术的带动下,植物全基因组测序的热潮已经到来.对迄今开展的高等植物基因组测序工作进行简要回顾,并对未来的研究热点进行展望.  相似文献   

13.
Grey Willow (Salix cinerea L.) poses a significant threat to wetland ecosystems in New Zealand. To manage the ecological impacts and to control further spread, cost‐effective large‐scale control methods are needed. We investigated the response of Grey Willow and dominant wetland plant groups to the aerial boom‐spray application of glyphosate at 9 L/ha and triclopyr (amine) at 18 L/ha at three New Zealand wetlands. We found glyphosate substantially reduced the dominance of tall (>2 m) Grey Willow with commensurate increases in the dominance of most native plant groups. Triclopyr (amine) application resulted in poor Grey Willow control, was not associated with increased native plant group dominance, and some native plant groups declined where triclopyr (amine) was applied. We conclude that the aerial application of glyphosate is an effective large‐scale Grey Willow control tool and could be used to initiate the restoration of native plant communities in wetlands dominated by Grey Willow. But, evidence of Grey Willow recovery after control suggests that increases in native plant dominance will be reversed as Grey Willow re‐establish. Further research is needed to determine how to maintain and enhance native plant dominance after control, and to determine how to manage Grey Willow in fen areas where the Grey Willow canopy is discontinuous and nontarget herbicide impacts can occur. The aerial boom‐spray application of triclopyr (amine) for large‐scale Grey Willow control should be discontinued as it does not provide effective control and results in negative ecological outcomes.  相似文献   

14.
土壤植物营养与农产品品质及人畜健康关系   总被引:13,自引:3,他引:10  
综述了土壤中Ca,Mg,S,Zn,Fe等中微量营养元素及Se,I等有益元素的丰缺情况,概述了矿质营养元素和有机物质对农产品品质的影响与人畜健康的关系,展望了今后应预以加强的研究方向,为进一步开展土壤植物营养与产品品质的研究提供参考。  相似文献   

15.
Boom‐bust dynamics – the rise of a population to outbreak levels, followed by a dramatic decline – have been associated with biological invasions and offered as a reason not to manage troublesome invaders. However, boom‐bust dynamics rarely have been critically defined, analyzed, or interpreted. Here, we define boom‐bust dynamics and provide specific suggestions for improving the application of the boom‐bust concept. Boom‐bust dynamics can arise from many causes, some closely associated with invasions, but others occurring across a wide range of ecological settings, especially when environmental conditions are changing rapidly. As a result, it is difficult to infer cause or predict future trajectories merely by observing the dynamic. We use tests with simulated data to show that a common metric for detecting and describing boom‐bust dynamics, decline from an observed peak to a subsequent trough, tends to severely overestimate the frequency and severity of busts, and should be used cautiously if at all. We review and test other metrics that are better suited to describe boom‐bust dynamics. Understanding the frequency and importance of boom‐bust dynamics requires empirical studies of large, representative, long‐term data sets that use clear definitions of boom‐bust, appropriate analytical methods, and careful interpretations.  相似文献   

16.
代谢组学及其应用   总被引:18,自引:0,他引:18  
对代谢组学的概念、特性、发展历史做了简要介绍,综述了当前代谢组学研究中的数据采集、数据分析中采用的技术,及代谢组学在疾病诊断、药物毒性研究、植物和微生物等邻域的应用,并对代谢组学的发展作了展望。  相似文献   

17.
菌根(mycorrhiza)是真菌与植物之间形成的最广泛的共生体。菌根真菌(rnycorrhizal fungi)具有丰富遗传多样性、形态多样性、物种多样性、生态系统多样性和功能多样性。菌根真菌与植物协同进化,发挥生理生态功能,对促进农林牧业生产、保持生态系统的稳定及其可持续生产力具有重大而不可替代的作用。经过一个多世纪的研究发展,菌根学(mycorrhizology)——菌物学与植物学的杂交学科终于在21世纪诞生了。随着研究的深入,人们发现菌根学不仅与菌物学和植物学关系极为密切,而且还与生态学、土壤学、保护生物学、植物保护学、微生物学、食用菌学、园林园艺学、作物栽培与耕作学、昆虫学等密切相关。作为一门新兴学科,菌根学自身发展的同时,也大大促进了相关学科的进展。本文系统总结了菌根学对其他学科发展所作的贡献,旨在进一步加强菌根学与其他学科的交叉渗透,为菌根学与其他学科协同进化奠定理论基础、促进多学科合作研究,为21世纪生物学的更大发展注入新的活力。  相似文献   

18.
Accurate assessment of population trends is invaluable in wildlife management, particularly for identifying species which are of conservation concern, and consequently, reliable cost-effective methods for their determination are highly desirable. In a recent publication (Eur J Wildl Res 62:407–413, 2016), the authors apply a subsampling method, used in several studies to quantify population trends from citizen science data for butterflies, birds, and plants, to assess the status of West European hedgehogs (Erinaceus europaeus) in England. Whilst the findings may be in agreement with expert opinion, we argue that this type of approach does not adequately account for spatial bias common in mammal data and that without further evaluation it is unclear whether the result is reliable or simply coincidental. To explore this concern, we apply the method across a range of terrestrial mammal species and compare the resulting trends to other published studies. Our findings show that the method fails to reproduce the accepted qualitative trends for the majority of species. Furthermore, comparison of trends based on data obtained from different sources produced conflicting predictions suggesting that the method is indeed vulnerable to survey bias. We therefore conclude that at present, without additional modification to address survey bias, this is not a reliable method for predicting population trends for mammals. However, more generally, this raises questions about the validity of subsampling methods based on citizen science data, and we would urge future studies to exercise caution by performing analysis across a suite of species including those with known trends for validation.  相似文献   

19.
Nourishment has not the purpose to get enough to eat, but it is embedded in social trends of aestheticism, technologies, speed, individualization or defamiliarization. Eating and nutrition are instruments of styling and the conduct of life. Social differences are not diminished in the process of nourishing but eating stresses the distinguishing elements. The sociology of nourishment analyzes those changes and interpretes the ambivalence of such trends. This science adds special perspectives of the social sciences to the other sciences of nourishment.  相似文献   

20.
植物膜蛋白质组学是当前植物科学研究的热点领域。本文概论了蛋白质组学在植物膜蛋白研究中的应用,包括双向电泳前膜蛋白样品的制备以及植物质膜、液泡膜和其他膜蛋白组分的蛋白质组学研究进展,并介绍了植物膜蛋白质组学相关的数据库,最后对其发展作了展望。  相似文献   

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