我国芝麻主产区茎点枯病病原菌生物学特性分析

在国内首次对我国湖北、河南、安徽、江西等芝麻主产区进行了较大范围的芝麻茎点枯病病原采集和菌株分离,纯化培养得到35个菌株.通过比较病原菌在不同培养基、不同诱孢处理方式、不同诱孢培养条件等,确定适宜培养条件为普通PDA培养基28℃黑暗培养4～5 d切断菌丝,再培养4～5d,建立了一套较成熟的芝麻茎点枯菌株分离培养纯化技术...     

夹竹桃（Nerium indicum）皂甙对鲫鱼（Carassius auratus）幼鱼的影响

为了评价夹竹桃皂甙对非靶标生物的潜在危害,采用半静态法研究了不同浓度（0、5.89、20.12mg·L-1和80.76mg·L-1）的夹竹桃皂甙对鲫鱼幼苗的死亡情况、特定生长率、糖原、蛋白质含量、SOD酶活性和微核率的影响。结果表明,当夹竹桃皂甙处理浓度≤20.12mg·L-1时,处理组的鲫鱼在试验期间无死亡;而在80.76mg·L-1皂甙的处理下,鲫鱼5d后全部死亡。当皂甙染毒浓度达20.12mg·L-1时,随处理时间的增加,特定生长率、糖原和蛋白质含量逐渐下降,而SOD活性先上升后下降;在清水中恢复饲养7d后,鲫鱼幼苗特定生长率和SOD活性受到的抑制作用逐渐减弱,糖原和蛋白含量恢复至与对照组相比无显著差异。此外,微核试验表明夹竹桃皂甙对鲫鱼幼苗的微核率无影响。研究结果表明,夹竹桃皂甙对鲫鱼的毒性属低等毒性且未发现遗传毒性,但高浓度的皂甙能影响鲫鱼幼鱼的正常生理代谢,导致生长受到抑制,严重时可致其死亡。     

高变性芝麻富硒蛋白特性研究

本文研究了高变性芝麻饼粕中含硒量、生物效能、溶解性、分布及存在形式等特性,并采用 D 型大柱凝胶电泳分析其可溶性蛋白硒络合分子量范围为21KD-30KD。     

Effect of Climatic Variation on Yield of Sesame (Sesamum indicum L.) at Different Dates of Sowing

Although experiments have previously been carried out to determine the optimum sowing time of sesame, very few attempts have been made to determine the effects of macro and micro climatic variation on yield. Thus a field experiment was conducted at the University Research Farm, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, India on an Entisol (alluvial, sandy loam) in the summer seasons of 1996 and 1997 to assess the effects of macro and micro climatic variations on yield of sesame for various dates of sowing. The number of seeds per capsule of sesame was highest in the crop sown on 19 February, although up to the 18 April sowing there was no significant variation. There was no appreciable variation in thousand-seed weight with date of sowing. Crops sown on 19 February and 1 March produced statistically similar yields. The average reduction in yield of sesame was 78.5 and 213 %, respectively, for crops sown on 10 February and 28 April, compared with the crop sown on 19 February. The cultivar Rama produced higher yields than B-67 and Kanke-1. Ambient temperature above 30 °C up to 100 % flowering had a direct positive effect on sesame yield. Crop exposure to 60–70, 70–80 and  80 % relative humidity up to 100 % flowering had a direct negative effect. Temperature profile at 50 days after emergence (DAE), relative humidity at 60 DAE, and photosynthetically active radiation (PAR) at 30 and 40 DAE within the crop canopy had direct positive effects on yield. Regression models suggested that temperature profile and PAR within the crop canopy produced 72 and 35 % variation in yield, respectively.     

铜排斥型植物黄花月见草(Oenothera glazioviana)对铜胁迫的响应以及在铜污染土壤上的合理利用

为探究Cu对铜排斥型经济植物黄花月见草生长和生理特性的影响,以铜积累型植物海州香薷和铜敏感植物芝麻为对照,通过水培试验研究了Cu(50μmol·L-1)胁迫对三种植物根系生长、根尖质膜完整性、叶片叶绿素含量、膜透性、渗透调节物质含量、有机酸含量、必需营养元素吸收的影响。结果表明:Cu胁迫下三种植物根系生长均受到显著抑制,但黄花月见草和海州香薷的根尖质膜完整性较好,而芝麻的根尖质膜完整性受到严重伤害;Cu胁迫导致芝麻叶片细胞膜透性增加了130%、叶绿素含量相对于对照降低了6.9%,但对黄花月见草和海州香薷叶片膜透性、叶绿素含量没有影响。Cu胁迫下,三种植物体内苹果酸含量均显著增加;海州香薷和芝麻叶片中脯氨酸含量分别上升了37%和73%,而黄花月见草叶片脯氨酸含量变化不大。三种植物体内Cu积累与Zn、Fe、Mn的积累呈显著正相关,与Ca、K积累呈负相关。此外,通过盆栽试验发现,土壤中总铜含量不高于700 mg Cu·kg-1土对黄花月见草种子千粒重、种子油含量、油中γ-亚麻酸含量均没有显著影响,且种子铜含量符合国家食品卫生标准(GBT 5009.13—2003)。低廉的生产成本和较高的经济效益使得黄花月见草在合理利用Cu污染土壤中具有推广价值。     

Arbuscular mycorrhizal associations in sesame under low-input cropping systems

The abundance and composition of arbuscular mycorrhizal fungi (AMF) are generally low under managed agroecosystems in comparison to natural ecosystems. The objective of the study was to determine the composition and species richness of AMF associated with sesame under traditional low-input cropping system in Kerala, India. Wide variability in root colonization by AMF as well as spore density in the rhizosphere existed in sesame. Correlation between frequency of colonization (F%) and spore density as well as between these variables and soil characteristics showed a negative relationship. The fungal variables were influenced by soil factors such as pH, soil organic carbon (OC) and available nutrients. Frequency of colonization was positively correlated (P < 0.01) with soil pH and potassium (K) and negatively correlated with OC, nitrogen (N) and phosphorus (P). AM spore density was positively correlated with OC, N and P and negatively correlated with pH and K. Ten taxa of AMF belonging to the genera Acaulospora, Diversispora, Funneliformis, Gigaspora, Glomus and Scutellospora were associated with sesame, with the predominance of Funneliformis and Acaulospora in both frequency and relative abundance over a wider soil nutrient range. Soil characteristics appear to have a profound influence on the composition and species richness of AMF under traditional low-input cropping systems.     

芝麻NBS类抗茎点枯病相关基因的克隆与分析

根据前期获得的芝麻抗茎点枯病NBS RGAs序列与河南省芝麻研究中心提供的EST 序列比对结果,设计4对特异引物,从10个对茎点枯病表现不同抗性的芝麻品种中扩增得到16条RGAs（抗病基因同源序列）,GenBank登录号分别为KC477692～KC477707,它们编码的氨基酸序列均具有NBS （核苷酸结合位点）类型抗病基因的特征结构域。Blastx分析结果表明,16个RGAs基因编码的部分氨基酸序列与已知 NBS类抗病蛋白同源性为35％～52％。聚类分析发现这些RGAs基因聚为4类,且均为non TIR NBS类型,为进一步筛选芝麻抗茎点枯病基因奠定了基础。     

芝麻渍害研究进展

本文阐述了湿害对芝麻生长发育、生理生化的影响,芝麻耐渍性的适应机制、遗传多样性,耐渍性的评价方法等。指出今后应重点建立芝麻耐渍分子育种技术,深入研究耐渍基因,为发掘和培育耐渍性芝麻种质奠定基础。     

芝麻资源群体结构及含油量关联分析

【目的】推测芝麻资源群体材料的遗传变异、群体结构和分子亲缘关系,通过关联分析检测群体中影响含油量表型的位点,为芝麻高油育种及开展其它性状关联分析等提供科学依据。【方法】利用20对SSR引物、43对SRAP引物及16对AFLP引物,对来自芝麻核心品的216份芝麻资源进行遗传多样性分析、群体结构分析和含油量性状关联分析。【结果】共检测到338个等位变异,群体遗传多样性为0.2493、多态性信息含量为0.2090。群体结构分析将216份芝麻资源分为2个亚群（POP1和POP2）;其中,174份资源（80.56%）归属POP1亚群,42份资源（19.44%）归属POP2亚群。POP1亚群的遗传多样性（0.2180）、多态性信息指数（0.1840）等指标值都低于POP2亚群（分别为0.3190和0.2561）,表明POP2亚群内种质遗传变异更为丰富。AMOVA分析表明,亚群内的遗传变异（86.83%）极显著高于亚群间的遗传变异（13.17%）（P＜0.001）。关联分析重复检测出2年环境下与含油量性状极显著关联的分子标记8个（P＜0.01）。这8个标记的性状变异解释率变幅为0.0343（标记M20E16-8）-0.0587（标记SSR12-2),总的变异解释率为0.2846（2008年)和0.3801（2009年）。【结论】以216份来自中国芝麻核心品的资源构成自然群体,群体结构简单、遗传变异较为丰富,可以用于开展芝麻重要目标性状的关联作图。应用关联分析方法在2个年度环境下重复检出8个标记与含油量性状极显著关联（P＜0.01）,这些标记可能与含油量性状存在稳定、可靠相关联。     

静态顶空气相-质谱联用法分析神农香菊花蕾和花中的挥发性成分

利用顶空加热收集神农香菊花蕾和花的挥发性成分,运用GC-MS分离和鉴定挥发性成分的结构及相对含量。结果显示两个花期阶段共鉴定出52种挥发性成分,花蕾含44种,花中含47种,神农香菊由花蕾发展到花时,其主要成分α-水芹烯的含量明显降低,而对伞花烃的含量显著增高。α-水芹烯可能经过生理变化转化为对伞花烃,这为进一步研究神农香菊的挥发性成分提供了参考.