【作者】 车海彦；

【导师】 吴云锋；

【作者基本信息】 西北农林科技大学 ， 植物病理学， 2003， 硕士

【摘要】 本实验利用萃取，重结晶的方法从植物中提取出一种天然抗病毒物质，命名为WCT-Ⅱ。并对该物质的部分理化性质进行了测定，以烟草和烟草花叶病毒(TMV)组成的系统及西葫芦和西瓜花叶病毒2号(WWMV-2)组成的系统为研究对象，测定了WCT-Ⅱ的室内生物学防效，并对其抗病毒机制进行了深入研究。 WCT-Ⅱ纯晶是一种橘红色结晶，可溶于丙酮、乙醚和正丁醇，微溶于氯仿和乙醇，不溶于水和石油醚。红外、质谱及核磁共振图谱的分析确定该化合物为：Lanost-8-en-26-oic,3-alpha，12-alpha,-dihydroxy-24-methylene-，methylester。 药效实验表明，该物质对病毒病害有较好的防治效果。烟草在喷施浓度为120ppm时防效可以达到73.6％，西葫芦在喷施浓度为100ppm时防效可以达到52.6％。直接用WCT-Ⅱ处理病毒，采用枯斑半叶法和电镜检测发现，处理后的病毒致病力明显下降，病毒粒体大量发生断裂。 WCT-Ⅱ处理后，植物体内发生了一系列的生理生化变化。与对照相比，处理叶片叶绿素含量明显提高，表现为花叶症状减轻；过氧化氢酶活性明显受到抑制。烟草和西葫芦叶片匀浆和胞间液的几丁质酶和β-1，3—葡聚糖酶和对照相比，酶活性都明显增加；对叶片匀浆和胞间液的蛋白经SDS-PAGE不连续电泳发现，处理后的烟草叶片胞间在第5—9天和第7天分别存在1条酸溶性蛋白和1条碱溶性蛋白；西葫芦叶片匀浆中在第3-9天存在1条特异酸溶性蛋白条带。上述结果说明，WCT-Ⅱ具有诱导植物产生抗病性的能力。 WCT-Ⅱ作为一种天然的抗病毒物质，对植物病毒病的防治是多方面作用的综合结果。它的防病机理主要表现在体外钝化病毒，诱导植物产生抗病性(提高叶绿素含量、抑制过氧化氢酶活性、提高几丁质酶和β-1，3葡聚糖酶活性、诱导产生PR(蛋白)等方面。该物质具有生物活性高，对动植物无毒，安全性高的特点，相信会有较好的应用前景。更多还原

【Abstract】 WCT- II is a kind of antiviral material, which is withdraws from the plant by extraction and the heavy crystalloid . In this study , we analyzed its physical and chemic properties. We take tobacco mosaic virus and tobacco , watermelon mosaic virus-2 and vegetable marrow as objects , measure control effects of WCT- II indoors and research on antiviral physiological-biochemistry mechanism of WCT-II.WCT- II is a kind of orange crystal, can dissolve in the acetone , ethyl ether and n-butyl alcohol ,tiny dissolve in the chloroform and alcohol, can’t dissolve in the water and petroleum ether . By IR , MR and HMR , WCT- II is lanost-8-en-oic , 3-alpha , 12-alpha-dihydroxyl-24-methylene-ethylester.WCT- II can control virus diseases by biological control effect. The efficiency is 73.6 % , when WCT- II is sprayed on tobacco at 120ppm ;The efficiency is 52.6% , when WCT - II is sprayed on vegetable marrow at 1 OOppm . After treated by WCT- II, virus pathogen-icity obviously decrease by withered spot half leaf’s method and virons break up in large number by electron microscopy .The plant occur a series of physiological-biochemistry changes by WCT- II. Compare with check , chlorophyll’s quantities obviously increase , mosaic symptom alleviate . Cata-lase activity is obviously inhibited . Chitinase activity and beta- 1, 3 - glucanase activity in leaves and intercellular compared with control are obviously increased ; the proteins existed in leaves and intercellular is analyzed through SDS-PAGE , the result show that a specific acid-soluble protein during the 5th-9th day and a specific basic-soluble protein in the 7th day exist in tobacco’s intercellular, a specific acid-soluble protein exist during the 3rd-9th day in vegetable marrow’s leaves .WCT- II is a kind of antiviral material from plants . It has some antiviral mechanisms , which can primarily blunt virus outside and induce the host resistance (increase quantities of the chlorophyll, repressed catalase activity , increase chitinase activity and P - 1, 3 -glucanase activity , induce the PRs ). High biological activity WCT- II is nontoxic and safe to animals and plants . It will be applied extensively in the future .更多还原