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关键词： lower atmosphere   vehicle   phase error   drone honey bees   flight   Unmanned Aerial Vehicle   Sampling   velocity modulation   Plant pathogen   Wireless mesh networks  

摘要： Unmanned aerial vehicles (UAVs) are an important tool to track the long-distance movement of plant pathogens above crop fields. Here, we describe the use of a control strategy (coordination via speed modulation) to synchronize two autonomous UAVs during aerobiological sampling of the potato late blight pathogen, Phytophthora infestans. The UAVs shared position coordinates via a wireless mesh network and modulated their speeds so that they were properly phased within their sampling orbits. Three coordinated control experiments were performed August 14-15,2008. In the first two experiments, two UAVs were vertically aligned at two different altitudes [25 and 45 m above ground level (AGL)] with identical sampling orbits (radii of 150 m). In the third experiment, two UAVs shared the same altitude (35 m AGL) with different sampling orbits (radii of 130 and 160 m). Orbit times did not vary significantly between the two UAVs across all three aerobiological sampling missions, and the phase error during sampling converged to zero within 2 mm following the start of the coordinated control algorithm. Viable sporangia of P. infestans were recovered following two of the coordinated flights. This is the first detailed report of autonomous UAV coordination during the aerobiological sampling of a plant pathogen in the lower atmosphere. UAVs operating independently of one another may experience significant sampling variations during the course of a flight. Coordinating the flight of two or more UAVs ensures that the vehicles enter, sample, and exit a spore plume at consistent times. (C) 2010 Wiley Periodicals, Inc.

关键词： 细胞生物学   学术年会   专业委员会   植物   学会   中国   研究人员   南京市  

关键词： 竹子   生殖生物学   育种  

摘要： 本文介绍了国内外有关竹子的生殖生物学的研究概况,具体包括:竹子开花周期、花器构造、花粉萌发率、胚胎发育、结实情况、常规育种、人工诱导开花等方面的研究取得的进展。

关键词： 应急反应   细胞   ROP类基因  

摘要： 植物在生长发育过程中,不仅受到外界环境的影响,同时也有自身的调节系统对外界信号做出相应的应急反应,这种反应就是细胞的信号反应系统适应外界环境的过程,适者生存,不适者淘汰。ROP类基因属于植物体特有的细胞信号调节基因。现就目前茄科植物关于ROP类基因的相关研究进展进行综述,以期为ROP基因的进一步研究提供参考。

关键词： 植物   盐胁迫   应答   转录因子   生物学特性  

摘要： 逆境胁迫会激活植物的转录因子,转录因子结合到应答基因的顺式作用元件后可以启动应答基因的表达,调控并减轻逆境胁迫对植物的伤害,因而转录调控在植物对逆境胁迫的应答反应中具有重要的作用。本文对盐胁迫下参与植物应答反应的转录因子及其生物学特性进行了综述,并对这些转录因子在植物耐盐基因工程中的应用前景作出了展望。

关键词： 生物化学技术   分子生物学技术   植物微生物生态学  

摘要： 植物微生物生态学是研究植物微生态系统的一门学科,以植物组织细胞内微生物的组成、功能、演替,以及微生物之间和微生物与宿主之间的相互作用关系为研究对象。现代生物化学与分子生物学技术在植物微生物生态学研究领域的作用日益明显。介绍了上述技术及其在植物微生物生态学研究领域的应用进展,并对其在该领域的利用和发展进行了展望。

关键词： 生物合成途径   茉莉酸类物质   茉莉酸   次生代谢  

摘要： 茉莉酸类物质(JAs)是新确认的一类广泛存在于植物体内的内源激素,在植物的生长发育、应激反应和次生代谢过程中起着重要的调控作用。该文主要概述了植物中茉莉酸类物质的生物合成途径、各关键酶的生理作用及其在植物次生代谢工程等方面的研究进展,并探讨了茉莉酸类物质的潜在应用价值。

关键词： Phytohormone   Auxin biology   Hormone signalling   Root development  

摘要： Like animals, plants have evolved into complex organisms. Developmental cohesion between tissues and cells is possible due to signaling molecules (messengers) like hormones. The first hormone discovered in plants was auxin. This phytohormone was first noticed because of its involvement in the response to directional light. Nowadays, auxin has been established as a central key player in the regulation of plant growth and development and in responses to environmental changes. At the cellular level, auxin controls division, elongation, and differentiation as well as the polarity of the cell. Auxin, to integrate so many different signals, needs to be regulated at many different levels. A tight regulation of auxin synthesis, activity, degradation as well as transport has been demonstrated. Another possibility to modulate auxin signaling is to modify the capacity of response of the cells by expressing differentially the signaling components. In this review, we provide an overview of the present knowledge in auxin biology, with emphasis on root development. (C) 2010 Published by Elsevier Masson SAS on behalf of Academie des sciences.

关键词： SYSTEMS biology   AUXIN   DIFFERENTIAL equations   BIOLOGICAL systems  

摘要： Background: Stochastic and asymptotic methods are powerful tools in developing multiscale systems biology models;however, little has been done in this context to compare the efficacy of these methods. The majority of current systems biology modelling research, including that of auxin transport, uses numerical simulations to study the behaviour of large systems of deterministic ordinary differential equations, with little consideration of alternative modelling frameworks. Results: In this case study, we solve an auxin-transport model using analytical methods, deterministic numerical simulations and stochastic numerical simulations. Although the three approaches in general predict the same behaviour, the approaches provide different information that we use to gain distinct insights into the modelled biological system. We show in particular that the analytical approach readily provides straightforward mathematical expressions for the concentrations and transport speeds, while the stochastic simulations naturally provide information on the variability of the system. Conclusions: Our study provides a constructive comparison which highlights the advantages and disadvantages of each of the considered modelling approaches. This will prove helpful to researchers when weighing up which modelling approach to select. In addition, the paper goes some way to bridging the gap between these approaches, which in the future we hope will lead to integrative hybrid models.

关键词： development   food utilization   longevity   oviposition   survival   Chinese cabbage   cowpea   sweet potato   tobacco  

摘要： Effects of four host plants, tobacco, Chinese cabbage, cowpea and sweet potato, on larval and pupal development and survival, and longevity and fecundity of adults of Spodoptera litura (F) (Lepidoptera: Noctuidae), were studied under laboratory conditions (26 degrees C, 60-80% RH), as was the utilization of the four host plants and adaptation on tobacco. All of the biological parameters included in the study were affected by the host plants. In a choice test, S. litura females oviposited most on Chinese cabbage, least on tobacco, and intermediate on cowpea and sweet potato. S. litura larvae developed differently on the four host plants, from shortest to longest in the following order: Chinese cabbage, cowpea, sweet potato, and tobacco. Pupal development was shorter on cowpea than on the other three host plants, and males generally developed longer than females. More females than males were found among emerged adults, and male adults lived 1-2 d longer than females. Larvae survived best on cowpea (81.6%), followed by Chinese cabbage (75.5%), then sweet potato (66.1%), and worst on tobacco (49.2%). Pupal survival rates were relatively high (91.4-95.9%) in all four host plant treatments, although that on sweet potato was lower than those on the other three host plants. Pupal weights on tobacco and sweet potato were similar, but both were lower than those on Chinese cabbage and cowpea. Generally, male pupae weighed less than female pupae. Numbers of eggs oviposited by female S. litura were highest on sweet potato, followed by those on cowpea, Chinese cabbage, and lowest on tobacco. Relative food consumption rate was highest on sweet potato, followed by that on cowpea, Chinese cabbage, and lowest on tobacco. In contrast, S. litura larvae that fed on tobacco had higher efficiency of conversion of digested food, highest efficiency of conversion of ingested food, and lowest approximate digestibility as compared with larvae that fed on other host plants. The potential causes