不同提取缓冲液对三尖杉DNA 提取质量的影响

采用CTAB法研究不同提取缓冲液对三尖杉DNA 提取质量的影响。结果表明：提取三尖杉DNA的最佳缓冲液所含物质及浓度为100 mmol·L-1TrisHCl pH 8.0+0.14 mol·L-1NaCl+2%CTAB+20 mmol·L-1EDTA +2%β 巯基乙醇。采用改进的CTAB法提取了15个三尖杉优树样品的DNA,提取的DNA质量均较高,可以满足分子标记分析的要求。     

西藏色季拉山冷杉群落结构健康评价

选择西藏色季拉山急尖长苞冷杉天然林为研究对象,在海拔梯度上以群丛作为评价的基本单位,进行冷杉群落结构健康评价。对群落物种多样性和群落结构特征因子,采用主成分分析,筛选主要评价指标,结合层次分析法(AHP法)进行健康排序。结果表明,对冷杉林群落结构健康影响最大的因子依次为:年龄结构、灌木层盖度、乔木株数、更新数量、草本种类、郁闭度、草本层盖度、灌木种类、乔木种类和亚层数共10个因子。健康排序次序为急尖长苞冷杉-林芝云杉群丛、急尖长苞冷杉+忍冬群丛、急尖长苞冷杉+杜鹃群丛、急尖长苞冷杉+苔藓群丛。     

Potential for the alleviation of arsenic toxicity in paddy rice using amorphous iron-(hydr)oxide amendments

Abstract

A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice (Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L^?1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces.     

羊驼呼吸系统形态结构观察

用大体解剖学方法研究了羊驼呼吸系统的形态结构,用组织学方法研究了羊驼肺的组织结构,并与文献报道的骆驼的呼吸系统,牛、羊、马、猪等的呼吸系统进行了比较。结果显示,羊驼呼吸系统的组成与其它家畜相同,都是由鼻、咽、喉、气管、支气管和肺组成,但各器官有其特点。羊驼呼吸系统形态结构类似于骆驼和马,肺的组织结构类似于其它家畜,但也有其独特之处。     

大白菜延伸DNA纤维的制备和检测(英文)

[目的]制备和检测大白菜延伸DNA纤维。[方法]以大白菜幼叶为材料,采用刀切分离细胞核、SDS释放DNA、盖玻片滑动牵拉DNA的方法,首次获得大白菜DNA延伸纤维。[结果]以基因组DNA和25SrDNA为探针进行原位杂交检测,该DNA纤维长度大约为1.93Mb,25SrDNA在大白菜基因组中的拷贝数在258-687之间。该方法获得的DNA延伸纤维平行、清晰、适合FISH分析。[结论]该研究将会促进大白菜基因图谱的构建和组织分析。     

葡萄核心种质的构建

【目的】在已建立的葡萄初级核心种质的基础上,利用SSR分子标记技术构建葡萄核心种质。【方法】利用M策略（Core Finder和Power Core）、遗传距离法（least distance stepwise sampling,LDSS和genetic distance optimization,GDOPT）和Core Hunter法构建核心种质, 并对He、Ho和 I值等遗传多样性指数和方差差异百分率（VD%）、均值差异百分率（MD%）、极差符合率（CR%）和变异系数变化率（VR%）等表型指标进行统计检验,同时采用SSR和SRAP分子标记的主坐标分析对其进行确认。【结果】M策略构建的核心种质能保留初级核心种质全部的等位基因,遗传距离法抽取的核心种质对原始种质具有较好的代表性。为使所构建的核心种质具有最大的遗传距离和最大的遗传多样性,对M策略、遗传距离法和Core Hunter法构建的核心种质进行了合并,48份葡萄核心种质以最少的种质材料保留了初级核心种质96.21%的等位基因,以5.53%的取样比例代表了原始整体种质92.90%的遗传多样性。【结论】经分子和表型检验,所构建的核心种质具有较好的代表性和遗传多样性。同时本研究所采用的方法对其它作物核心种质的构建具有重要的参考价值。     

外源硝酸钙对盐胁迫黄瓜幼苗生长和光合作用的影响

以较耐盐黄瓜品种新泰密刺为试材,采用营养液栽培,研究了叶面喷施Ca(NO3)2对盐胁迫(65 mmol/L NaCl)下黄瓜幼苗生长、叶片叶绿素含量、光合及叶绿素荧光参数的影响。结果表明,外源Ca(NO3)2显著提高了盐胁迫下黄瓜幼苗的干鲜重和叶片叶绿素含量;Ca(NO3)2也提高了盐胁迫下黄瓜叶片净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、PSⅡ实际光化学效率(ФPSⅡ)、光条件下最大光化学效率(F'v/F'm)和光化学淬灭系数(qP),而对胞间CO2浓度(Ci)、暗条件下最大化学效率(Fv/Fm)和非光化学淬灭系数(qN)没有显著影响。这些结果说明外源Ca(NO3)2可能通过提高叶绿素含量和调节气孔限制,以缓解盐胁迫对黄瓜幼苗光化学效率的抑制,进而提高植株耐盐胁迫能力,促进其生长。     

马蔺药学研究概况

在广泛文献检索基础上,对马蔺的成分、药理(主要表现为抗癌活性)及临床应用(种子、根、花、叶等)进行了概述,为其深入开发利用提供参考。     

梅花产业化的探讨——以莱州市宏顺梅园为例

莱州种植梅花历史悠久,现有大量的梅花种植专业大户开始涌现。梅花生产形成产业化,仅靠农民自发种植远远不够,必须解决好生产的规模化、规范化问题。为了推动梅花产业的发展,须成立梅花行业协会,订立协会章程、制度,规范会员行为,并对会员优先发放梅花新品种,优先进行技术培训,统一梅花盆景的销售价格。依靠科技谋发展,获国家专利的"大杏树嫁接梅花"技术将梅花产业的健康快速发展推向了一个新境界。     

甲氨基阿维菌素苯甲酸盐与杀虫双对斜纹夜蛾毒力最佳配比筛选

[目的]筛选出对斜纹夜蛾具有增效作用的甲氨基阿维菌素与杀虫双最佳配比,为其混剂研发及现场桶混应用提供科学依据.[方法]采用浸叶法测定甲氨基阿维菌素、杀虫双单剂及其混剂对斜纹夜蛾3龄幼虫的毒力,筛选出具有增效作用的最佳配比.[结果]甲氨基阿维菌素:杀虫双为70∶30和60∶40即有效成分质量比为0.14∶243.00和0.12∶324.00时毒效比分别为1.34和1.45,表现出增效作用,其共毒系数分别为125.93和151.08.[结论]甲氨基阿维菌素与杀虫双按有效成分质量比为0.12∶324.00混配时,对斜纹夜蛾幼虫的毒力增效作用最明显,为防治斜纹夜蛾的最佳配比.