Effect of Trichoderma asperellum and arbuscular mycorrhizal fungi on cacao growth and resistance against black pod disease

Arbuscular mycorrhizal fungi (AMF) and members of the genus Trichoderma have emerged as promising groups of microbial inoculants that can induce plant growth and resistance to disease. This study aimed at investigating the potential of AMF and a strain (PR11) of Trichoderma asperellum to promote cacao growth and induce resistance against Phytophthora megakarya. Cacao seedlings were either non-inoculated, or inoculated with the saprophytic fungus T. asperellum and/or a mixture of two different mycorrhizal fungi, Gigaspora margarita and Acaulospora tuberculata. Eighteen weeks after planting, a series of morphological as well as biochemical changes, which are considered to be part of the plant defense response, were measured after a challenge inoculation of the leaves with zoospores of P. megakarya. Inoculation with AMF and T. asperellum alone was essential for the promotion of plant growth. Significant increase in plant height, root and shoot fresh weights, as well as phosphorous uptake was recorded in comparison to non-inoculated control plants. However, dual inoculation of cacao seedlings with T. asperellum and AMF did not always positively benefit the plants. Leaf inoculation showed variation among the treatments, with the lowest disease index (highest level of resistance) recorded in plants inoculated with either AMF or T. asperellum only. This came along with a high synthesis of amino acids and phenolic compounds in both healthy and infected leaves, suggesting that these metabolites are implicated in disease resistance.     

茶树遗传育种研究最新进展

本文重点总结了2010年国内外茶树遗传育种研究的进展,包括茶树育种资源研究、基因克隆与分子育种、茶树品种化学成分与适制性研究、茶树品种生理和抗性育种、茶树品种繁育与栽培以及茶树新品种选育等方面取得的研究成果。     

栽培大豆种质资源耐盐性的研究进展

评价、筛选并利用栽培大豆的耐盐种质资源,对开发利用盐渍土具有极其重要的意义。从耐盐性评价方法、耐盐的生理生化基础、耐盐的分子生物学基础及耐盐种质的筛选与创新等方面,总结了当前栽培大豆种质资源耐盐性研究现状,分析了目前研究中现存的问题。指出今后的研究要在提高盐胁迫的盐浓度并增加盐种类的基础上,结合利用先进的生物技术和试验手段,以及配合新种质的发现和应用,全面系统的开展鉴定评价研究,实现栽培大豆耐盐种质资源的创新利用。     

GIS技术在人工影响天气作业气象探测资料分析中的应用

笔者以焦作市人工影响天气作业指挥系统为实例,分析了气象探测资料在人工影响天气作业指挥中的综合处理应用,介绍了组件式GIS技术在人影作业指挥系统中应用的总体思路,并阐述了该系统中GIS应用的主要方面,包括离散点探测资料的分析处理、雷达资料处理显示、各类探测资料的融合叠加、精细化预报产品的图形化显示及火箭安全射击范围管理、区域协作区管理等。实现了人工影响天气作业指挥中气象探测数据、预报预警信息、火箭射击区域等数据的空间管理,基于GIS可以对作业效果进行科学评估。     

播种深度和播后淹水时间对冬小麦出苗率及冬前幼苗质量的影响

为探讨淹水时间和播种深度对不同小麦品种出苗率及冬前幼苗健壮程度的影响,在控制条件下对四个不同类型品种进行了研究,结果表明：播种后淹水1-4天,可导致五种播深TN18的平均出苗率降低22.43%,越冬期单株干物重降低21.56%;JM20分别降低23.43%和18.46%;SN8355分别降低9.66%和19.86%;LM14分别降低6.21%和23.20;说明淹水对TN18 JM20两品种出苗率的影响显著低于SN8355和LM14。淹水可使3cm地温降低0.470C,5cm降低1.150C。在淹水时间相等条件下,随播种深度的增加,对出苗率和幼苗质量的影响逐渐增大;在播深相同时,淹水时间越长影响越大。在播深2cm～6cm范围内,播种越浅出苗率和越冬期单株干物重越高,淹水对其的影响也越小,浅播是降低渍涝地区渍涝灾害的有效措施;但由于浅播分蘖节基本处在2cm处,不利于抗寒和抗旱,因而该结果仅适于渍涝麦田应用。     

Characterisation of QoI‐resistant field isolates of Botrytis cinerea from citrus and strawberry

BACKGROUND: In 2004, field isolates of Botrytis cinerea Pers. ex Fr., resistant to strobilurin fungicides (QoIs), were first found in commercial citrus orchards in Wakayama Prefecture, Japan. Subsequently, QoI‐resistant isolates of this fungus were also detected in plastic strawberry greenhouses in Saga, Ibaraki and Chiba prefectures, Japan. Biological and molecular characterisation of resistant isolates was conducted in this study. RESULTS: QoI‐resistant isolates of B. cinerea grew well on PDA plates containing kresoxim‐methyl or azoxystrobin at 1 mg L^?1, supplemented with 1 mM of n‐propyl gallate, an inhibitor of alternative oxidase, whereas the growth of sensitive isolates was strongly suppressed. Results from this in vitro test were in good agreement with those of fungus inoculation tests in vivo. In resistant isolates, the mutation at amino acid position 143 of the cytochrome b gene, known to be the cause of high QoI resistance in various fungal pathogens, was found, but only occasionally. The heteroplasmy of cytochrome b gene was confirmed, and the wild‐type sequence often present in the majority of resistant isolates, indicating that the proportion of mutated cytochrome b gene was very low. CONCLUSION: The conventional RFLP and sequence analyses of PCR‐amplified cytochrome b gene are insufficient for molecular identification of QoI resistance in B. cinerea. Copyright © 2009 Society of Chemical Industry     

紫茎泽兰在湖北地区的入侵风险评估

紫茎泽兰是我国危害最严重的入侵物种之一,据已有路线分析有入侵华中地区的风险。在武汉同质种植园中建立了不同年份（2009年和2012年）从西昌采回的紫茎泽兰种群,将2种群进行枝条扦插,比较了扦插苗的株高、茎宽、比叶面积、叶干物质含量、叶片C/N等生长参数和抗虫性,从中分析紫茎泽兰入侵种群在新引入地,随引入时间的表型变化响应。结果表明紫茎泽兰叶片C/N在两种群间差异不显著,但株高、茎宽、比叶面积、叶干物质含量和抗虫性,生长3年的种群均显著大于生长1年的种群,表现出明显的表型可塑性,其中比叶面积和叶干物质含量在两种群均为负相关关系。在新入侵地（缺乏专食性昆虫）,随引入时间的延长,植株的适应能力增强,获取资源的能力提高,对广食性昆虫的抗性增强。由于防御广谱天敌的物质含量低,合成成本低,植物把资源主要用于自身的生长。因此我们应在入侵早期对紫茎泽兰进行防治,这样才能更有效的控制其传播。     

吉尔吉斯斯坦与新疆土壤测定方法对比分析

为了了解吉尔吉斯斯坦国家土壤养分的测定方法,研究不同区域土壤养分测定结果的差异性,加强区域土壤养分管理的合作与交流,采集吉尔吉斯斯坦国家不同地区、不同土壤类型的土壤样品,样品分成2份,分别用新疆和吉尔吉斯斯坦本地常规的分析方法测定土壤的有机质和全氮含量,分析不同测试结果的差异性及相关性。结果表明：（1）土壤有机质和土壤全氮含量均表现出极显著的线性相关关系;（2）不同测试方法下土壤有机质、全氮表现显著的线性相关关系。中国新疆和吉尔吉斯斯坦土壤有机质和全氮的测定方法虽然不相同,但是测定数据结果基本一致,表现出高度的相关性。     

北京地区不同类型社区的景观差异性研究

[目的]新型城镇化背景下,为了加强城市社区、乡村社区、城乡结合部社区景观的协同发展,从而研究不同类型社区景观的差异性.[方法]以北京地区为例在论述社区景观重要性的基础上,根据地理位置差异将社区分为三类,分别从行为、空间和景观元素三方面分析其景观差异性.[结果]探索从行为到空间再到景观的社区景观设计方法.[结论]研究结果可为社区景观营造提供建议,对不同类型社区景观的协同发展和新型城镇化建设有现实意义.     

半干旱采煤塌陷区植被土壤碳循环及源、汇功能转换特征

以大柳塔矿区采煤塌陷前后不同草地为研究对象,以区域实测数据为基础,分析了0—80cm土层土壤有机碳储量变化以及春季、夏季、冬季3个季节不同植被部位以及土壤碳循环差异及碳源/汇功能转换特征。结果表明:(1)对照区和沉陷区不同季节土壤碳储量都具有明显的垂直分布特征,采煤沉陷造成春季草地生态系统土壤碳储量显著下降(P=0.001),随季节变化呈现出冬季夏季春季的趋势;(2)采煤沉陷造成草地生态系统春季地上立枯和枯落物碳储量显著上升(P=0.000,P=0.004),冬季枯落物和根系碳储量下降(P=0.016,P=0.015),沉陷区不同植被部位碳储量随季节变化均呈现出春季夏季冬季的趋势;(3)相较对照区,沉陷区植被碳储量随季节变化均表现为碳源过程,土壤碳储量随季节变化由碳源—碳汇过程转变为碳汇过程;(4)相关分析显示,对照区地上新鲜植被碳储量和立枯碳储量呈现出显著的负相关性(P0.05),而沉陷区地上新鲜植被碳储量和立枯碳储量呈现出极显著的正相关性(P0.01)。