摘要: The effect of salicylic acid (SA) on stomatal aperture of 3～4 weeks' Vicia faba L. under different conditions was investigated. It was shown that stomatal closure responded to SA after 3 hours treatment. The concentration and pH of SA solution at different media affeeted SA to different extents. The degree of effects was concentration-dependent. With increasing SA concentration, the promotion effect on stomatal closure was enhanced. At 10 -3 mol L -1 SA exerted the most effect. The effect of SA was dependent on the pH of the solution. In the range of 10 -6 ～10 -3 mol L -1 as pH decreased, the effect of SA on stomatal closure was enhanced. SA 10 -4 mol L -1 in distilled water at pH 4 the percentage of inhibition on the stomatal aperture was 67%, while at pH 7 the percentage of inhibition was only 20%. The degrees of SA effect on stomatal aperture in distilled water、MES buffer solution and citric acid buffer solution were different. In MES buffer the effect of SA was lower than that in distilled water, or in citric acid buffer.

摘要: 稀土元素是镧系金属元素的总称，在地壳中含量稀少，约占１５×１０－６．我国对稀土元素的开发利用较早，特别是农业上稀土多元复合肥常与农药一起使用，这对生物和环境的影响为人们所关注，给环境研究带来了新课题．目前对稀土元素的研究主要集中在地球化学、农业化学和...

摘要: 从杭州市郊的大豆病株上获得一病毒分离物Ｓ１，温室人工摩擦接种７科１６种植物，Ｓ１能侵染其中的５科１４种植物．Ｓ１能由桃蚜、豆蚜以非持久性方式传毒，该分离物的钝化温度为５０～５５℃，稀释限点为１０－３～１０－４，体外保毒期为３～４ｄ（２５℃）．用昆诺藜作繁殖寄主可提到大量球状病毒粒子，ｄ为２５～３０ｎｍ．病毒外壳蛋白主要由两种亚基构成，Ｍｒ分别为４４．７×１０３和２１．９×１０３，病毒基因组由两条ＲＮＡ分子组成，大小分别为６．２ｋｂ与３．８ｋｂ，Ｎｏｒｔｈｅｒｎｂｌｏｔ结果显示３．８ｋｂＲＮＡ与ＢＢＷＶ２蚕豆分离物ＲＮＡ２ｃＤＮＡ有明显杂交反应．病毒粒子电泳后产生相似于豇豆花叶病毒科的快、慢两个电泳型．琼脂双扩散试验中，Ｓ１和ＢＢＷＶ２均能与蚕豆萎蔫病毒２（ＢＢＷＶ２）抗血清形成明显沉淀线，且沉淀线互相融合，Ｗｅｓｔｅｒｎ检测亦表明，此分离物的大小亚基均可与ＢＢＷＶ２抗血清反应．根据以上特性，Ｓ１分离物被鉴定为ＢＢＷＶ２．

摘要: 利用RAPD技术对家蚕限性普斑品种SC1的雌雄体分别进行PCR扩增通过120种引物的筛选，得到1个雌体特异的RAPDDNA片段将该片段克隆到pUC19质粒，井进行了限制性内切酶图谱分析.

摘要: 研究了土壤镉对桑叶含镉量［w（Cd）］、含水量［w（H2O）］的影响以及镉对蚕生长发育和蚕茧质量的影响结果表明：（1）桑叶w（Cd）与土壤w（Cd）呈极显著正相关（2）土壤w（Cd）＞22．3×10-6,则桑叶w（H20）＜75％，叶质开始变粗硬,（3）用w（Cd）＜3．66×10-6的添加Cd桑叶养蚕时，蚕能正常生长发育，蚕茧质量不受影响（4）当镉由土壤进入桑叶，用w（Cd）＜0．49×10-6的桑叶养蚕时，蚕的生长发育和蚕茧质量不受明显影响（5）当桑叶w（Cd）超过上述数值后，蚕的生长发育受阻，蚕茧质量明显下降。