耕作方式对麦红吸浆虫种群动态的影响

为了解不同耕作方式对麦红吸浆虫Sitodiplosis mosellana （Géhin）种群动态的影响, 2010年和2011年, 在中国科学院河北省栾城农业生态系统试验站不同耕作方式的小麦样地中, 通过淘土、 成虫网捕和剥穗等方法对麦红吸浆虫进行了调查研究。结果表明： 两年取土筛检出的幼虫数量依次为秸秆还田免耕田>秸秆站立免耕田>秸秆还田旋耕田, 但2011年网捕调查显示, 秸秆还田旋耕田中的成虫数量高于另外两种样地。两年剥穗检查出的幼虫数量的排序与取土筛检出的幼虫数量的排序相反, 依次为秸秆还田旋耕田>秸秆站立免耕田>秸秆还田免耕田。分析表明免耕有利于幼虫的越冬, 但免耕田麦穗受害较轻。旋耕对幼虫越冬不利, 但抽穗后受害较严重。在耕种方式是旋耕的情况下, 漫灌可加重吸浆虫的危害。研究结果有助于进一步了解大范围耕作方式的变迁对麦红吸浆虫发生的影响。     

河南濮阳市小麦吸浆虫发生规律的调查与防治

调查了河南省小麦吸浆虫病的发生和分布情况,分析了小麦吸浆虫的发生与小麦品种、土质的关系,并成功地防治了小麦吸浆虫的大面积发生。     

小麦吸浆虫类似种幼虫的种类和发生量

自80年代以来,小麦吸浆虫再次猖獗为害,引起各级农业部门高度重视。近年我们在调查研究中,发现麦田存在与小麦吸浆虫同时混合发生的类似种,它们在形态、体色和一些习性上十分相似。幼虫体形小、蛆状,都具鲜明色彩,很像麦红吸浆虫Sitodiplosismosellana（Gehin）的幼虫橙黄色,也像麦黄吸浆虫Contariniatrifici（Kirbg）的幼虫黄绿色,在土壤里结茧越夏和越冬,采用淘土法可淘获较大数量的幼虫体。根据满恩（M0bh）氏以胸骨片的形态特征区别种的重要特征方法,经比较发现在陕西咸阳麦田吸浆虫类似种幼虫有5类10种。发生这些类似种幼…     

小麦吸浆虫的生物学、生态学及防治研究进展

本文回顾了近期小麦吸浆虫的发生分布变化、扩散方式、生物学特性的遗传和生理基础、监测技术、抗性品种、生物防治和化学防治策略的主要进展,并展望了小麦吸浆虫研究未来的发展方向。     

七种杀虫剂对小麦吸浆虫和麦蚜防治效果研究

【目的】明确25%吡蚜酮SC、3%甲氨基阿维菌素苯甲酸盐ME、25%噻虫嗪WG、14%氯虫·高氯氟ZC、15%高氯·毒死蜱EC、2.5%高效氯氟氰菊酯EW和40%毒死蜱EC 7种杀虫剂对小麦吸浆虫和蚜虫的防治效果,为科学、合理用药防治小麦害虫提供参考。【方法】采用喷雾法和剥穗调查法,研究它们对小麦吸浆虫成虫和麦蚜的防效,及防后对小麦吸浆虫幼虫危害损失的影响。【结果】参试药剂药后1 d对小麦吸浆虫成虫防效均高于90%,药后3~5 d防效为84.81%~93.93%,防后挽回损失76%以上;对麦蚜药后1、3、5 d防效分别高于75%、80%和85%。在供试的7种药剂中,15%高氯·毒死蜱EC药后3~5 d对两种害虫防效、挽回吸浆虫危害均超过90%,应用效果最好;其次为25%噻虫嗪WG和40%毒死蜱EC,药后3~5 d对吸浆虫防效高于90%、对麦蚜防效分别高于86%和90%,挽回吸浆虫危害损失88%以上。【结论】供试药剂对小麦吸浆虫和麦蚜防效存在显著差异,15%高氯·毒死蜱EC对两种害虫防治效果最好。     

一种提取麦红吸浆虫基因组DNA的方法

介绍一种可从单头麦红吸浆虫Sitodiplosis mosellana(Gehin)成虫、幼虫和蛹成功地提取基因组DNA的方法。经检测提取DNA样品浓度为100～200ng/μL,纯度在1.4～1.6范围之间,以此为模板,可顺利地进行RAPD引物扩增。该提取方法简单、安全、经济,可为小型昆虫基因组DNA的提取提供参考。     

小麦种质抗吸浆虫鉴定及抗虫SSR标记开发

麦红吸浆虫(Sitodiplosis mosellana Géhin)是严重威胁小麦生产的重要害虫,其生活习性隐蔽,防治困难,筛选抗虫小麦种质及可用于抗虫性辅助选择的分子标记意义重大.本研究对我国不同麦区、不同时期的566份小麦种质资源进行了吸浆虫抗性鉴定,并尝试从抗虫性主效QTL所在基因组区段开发新的SSR标记.结果...     

小麦吸浆虫滞育幼虫甘油含量的季节变化(英文)

采用比色分析方法测定了小麦吸浆虫Sitodiplosis mosellana滞育期间幼虫甘油含量的季节变化。结果表明,幼虫离穗入土以前,甘油含量很低,仅为2.96±1.19μg/mg。幼虫离穗入土后,甘油含量急剧升高。入土后5d,甘油含量即上升为6.58±1.11μg/mg;至入土后17d,甘油含量达到高峰,12.21±2.21μg/mg。以后随时间的短期变化其含量变化不大,但随季节变化表现了一定的规律性,呈现了上升——下降——再上升——再下降的变化趋势,即夏季和冬季含量较高,秋季和春季含量较低。结茧幼虫和裸露幼虫比较,结茧幼虫的甘油含量在盛夏和冬季略高于裸露幼虫,秋季和春季时二者含量相当,两者在统计学上并无显著的差异。同一季节的当年滞育幼虫和进入第2年滞育幼虫的甘油含量无明显差异。由此可见,小麦吸浆虫幼虫滞育期间,甘油含量受季节或滞育深度的影响较大。     

小麦抽穗期与麦红吸浆虫成虫发生期的同步性及其受害程度

通过2012年在麦红吸浆虫发生田对小麦不同生育期进行套袋保护,明确了小麦抽穗期为麦红吸浆虫侵害的敏感期。采用生态位重叠率的计算方法,统计2012—2013年不同品种的抽穗期与麦红吸浆虫发生期的同步性,结果表明,同步性越高,产量损失越重,具有显著的相关关系。同时,品种抽穗期的成虫累计发生量与产量损失有显著的相关性。成虫发生期与抽穗期同步或吻合导致小麦受害而不是扬花期,所以在缺乏抗虫品种的情况下,应采取抽穗期化学保护进行防治。     

荒漠地区野生动物调查方法探讨——一种新的调查方法介绍

本文全面总结了我国野生动物调查的主要方法及应用,分析了已有方法在应用中的问题和缺陷,介绍了国际狩猎场的盘羊资源调查方法--地图样带法,并比较了该方法与样线法得出的调查结果差异和两种方法在实际应用中的区别.地图样带法没有长度和宽度概念,也没有规定样带的既定形状,提供了一种确定调查范围和计算样带面积的便捷方法,解决了过去调查中样带面积计算的难题.该方法完全根据实际调查的区域和地形地貌来确定样带的范围,使调查更具灵活性、机动性,并使密度的计算回归到了其本身的意义.该方法没有技术门槛,对广大基层野生动物保护工作者更具可操作性.     

小麦品种冀麦24抗麦红吸浆虫QTL分析

麦红吸浆虫是影响小麦产量和品质的重要害虫,研究小麦对吸浆虫抗性的遗传及其连锁分子标记对于提高抗虫品种的选择效率具有重要意义。本研究以小麦感虫品系6218与抗虫品种冀麦24产生的重组近交系(RIL)群体为材料,利用SSR标记和人工虫圃对冀麦24的抗虫性遗传进行了研究。结果表明:6218与冀麦24的抗性差异显著,RIL群体在2年2点的鉴定中抗性稳定;所构建的遗传连锁图谱包含112个SSR位点,形成26个连锁群,图谱全长835.7 cM,标记间平均距离为7.5 cM。利用QTL IciMapping的完备区间作图法,在4A染色体上检测到1个加性效应位点(QSm.hbau-4A),该位点在2个鉴定年度的贡献率分别为9.67%、10.57%。该抗性QTL及其连锁SSR标记的发掘,将有助于提高小麦抗吸浆虫育种的选择效率。     

释放天敌瓢虫和施用化学农药吡虫啉对麦田蚜虫的控制效果评价

以常规防治农药甲胺磷做对照,比较高效低毒化学农药吡虫啉和天敌昆虫瓢虫对田间麦蚜的防治效果。结果表明,施用10%吡虫啉可湿性粉剂300ghm2药后5d和10d的防效分别为15.1%和31.1%,对麦蚜防效理想。释放天敌昆虫瓢虫后5d和10d的防效分别为-347.6%和-171.7%,防效差,这是由于释放天敌后的强降雨所致。     

Research progress in BYDV resistance genes derived from wheat and its wild relatives

Barley yellow dwarf virus （BYDV） may cause a serious disease affecting wheat worldwide. True resistance to BYDV is not naturally found in wheat. BYDV resistance genes are found in more than 10 wild relative species belonging to the genera of Thinopyrum, Agropyron, Elymus, Leymus, Roegneria, and Psathyrostachy. Through wide crosses combining with cell culture, use ofph mutants, or irradiation, 3 BYDV resistance genes in Th. intermedium, including Bdv2, Bdv3 and Bdv4, were introgressed into common wheat background. Various wheat-Th, intermedium addition and substitution, translocation lines with BYDV-resistance were developed and characterized, such as 7D-TAi#1 （bearing Bdv2）, 7B-7Ai#1, 7D-7E （beating Bdv3）, and 2D-2Ai-2 （bearing Bdv4） translocations. Three wheat varieties with BYDV resistance from Th. intermedium were developed and released in Australia and China, respectively. In addition, wheat-Agropyron cristatum translocation lines, wheat-Ag, pulcherrimum addition and substitution lines, and a wheat-Leymus multicaulis addition line （line24） with different resistance genes were developed. Cytological analysis, morphological markers, biochemical markers, and molecular markers associated with the alien chromatin carrying BYDV resistance genes were identified and applied to determine the presence of alien, chromosomes or segments, size of alien chromosome segments, and compositions of the alien chromosomes. Furthermore, some resistance-related genes, such as RGA, P450, HSP70, protein kinases, centrin, and transducin, were identified, which expressed specifically in the resistance translocation lines with Bdv2. These studies lay the foundations for developing resistant wheat cultivars and unraveling the resistance mechanism against BYDV.     

An improved method for cell-to-cell transmission of infectious prion

Prion diseases are characterized by the accumulation of a pathological form of prion protein (PrP^Sc), which behaves as an infectious agent. Here we developed an in vitro co-culture system to analyze the PrP^Sc transmission from ScN2a cell, which persistently retains PrP^Sc, to naïve N2a cell. In this cell-to-cell transmission system, PrP^Sc transmitted to recipient N2a cell was able to be detected within 5-7 days. Further characterization showed that higher cell density greatly facilitated the transmission of PrP^Sc. This improved in vitro transmission method may become a useful tool for unveiling the molecular mechanism of PrP^Sc transmission.     

An improved method of genomic in situ hybridization (GISH) for distinguishing closely related genomes of tetraploid and hexaploid wheat species

An improved modification of genomic in situ hybridization (GISH) was proposed. It allows clear and reproducible discrimination between closely related genomes of both tetraploid and hexaploid wheat species due to preannealing of labeled DNA probes and prehybridization of chromosomal samples with blocking DNA. The method was applied to analyze intergenomic translocations 6A:6B and 1A:6B identified in the IG46147 and IG116188 samples of tetraploid wheat Triticum dicoccoides by C-banding. The structure of the rearranged chromosomes was defined for two translocation variants, and the breakpoints were identified on the chromosome arms. Possible application of the developed GISH variant to study genome reorganizations during speciation of allopolyploid plants in evolution is discussed.     

一种改进的粉虱成虫生物测定方法

生物测定是检测害虫抗药性的一项重要技术。利用100mL插口圆底聚丙烯离心管对现在应用较多的粉虱成虫生物测定方法——琼脂保湿浸叶法进行了改进。改进后的方法不影响粉虱成虫的持续取食,具有操作简单、结果重复性好及无需对成虫麻醉等优点。同时发现茄子叶片对于B型烟粉虱Bemisia tabaci(Gennadius)B-biotype和温室白粉虱Trialeurodes vaporariorum(Westwood)成虫均是一种非常适合的生测材料。利用该方法分3次独立测定了烯啶虫胺对B型烟粉虱和温室白粉虱混合日龄成虫的毒力,结果具有很好的重复性。     

Rapid evaluation of the efficacy of microbial cell removal from fabrics

The efficacy of microbial cell removal (EMR) from fabrics is a practically important indicator for the evaluation of cleansers and detergents. EMR is expressed quantitatively by the relative number of viable cells remaining on a fabric swatch after the treatment with these reagents. In order to count the viable cells on the swatch directly and rapidly, we have developed a unique microscopic imaging system with an ultra-deep focusing range. Standard swatches of cotton fabric were inoculated with microorganisms such as Pseudomonas fluorescence, Staphylococcus aureus, or Candida albicans. After the incubation on an agar medium, each swatch was treated with a fluorescent glucose, 2-[N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino]-2-deoxyglucose, to stain only viable cells. The images of every cell distributed within the surface layer with no greater than 130 μm thickness could be integrated into one image. Thus visualized cells could be counted automatically by a novel imaging program. Using a pair of cotton swatches (0.5×1.0 cm²) inoculated with C. albicans, EMR was evaluated quantitatively. Before washing, the total number of viable cells found on the observation area (3.8×10⁻⁴ cm²) was 288 cells. After washing with a test detergent, no cell (<1) was detected. For this case, EMR was given by the formula: log(288/<1)=greater than 2.5. The imaging and cell count of a test fabric could be performed within 1 h.