【作者】 张鑫；

【导师】 安德荣；

【作者基本信息】 西北农林科技大学 ， 植保资源利用， 2014， 硕士

【摘要】 马铃薯Y病毒（PVY）是一种世界性病毒，可侵染烟草（Nicotiana tabacum）、马铃薯（Solanum tuberosum）、辣椒（Capsicum spp.）、番茄（S.lycopersicum）等作物，引起植株花叶、畸形、矮化、斑驳，在烟叶上表现出脉带、脉坏死的症状，严重影响烟叶的产量和质量。实验室前期对12种真菌葡聚糖的抗病毒作用进行系统筛选，发现云芝葡聚糖具有很强的免疫增强作用，对TMV、CMV具有很强的预防作用，经葡聚糖处理能提高烟草产量和质量，将其应用于植物病毒病防治具有重要的研究价值，然而云芝葡聚糖的提取工艺尚不完善，其对PVY的抗性尚不明确。本研究通过筛选优良云芝菌株、比较两种提取工艺（水提醇沉与超声波提取）的多糖得率、优化菌丝体发酵条件（培养基、装液量、培养时间），优化提取云芝葡聚糖的工艺，以PVY枯斑寄主苋色藜（Chenopodium amaranticolor）、系统寄主心叶烟（Nicotiana glutinosa）为材料，半叶枯斑法、叶圆片法、室内盆栽试验测定云芝葡聚糖对PVY的保护、钝化、抑制增殖的效果，同时测定其对植株的诱导抗性及对烟草防御酶POD、PAL活性的影响，旨在为新型杀菌剂1.1%云芝葡聚糖水剂的防治应用提供依据。优化提取工艺试验结果表明：YZ-1比YZ-2菌丝体生长快，产量高，多糖得率高；酶、超声波法提取云芝葡聚糖，省时方便且多糖得率高；装液量为85mL的③号培养基中培养七天的发酵条件最适宜菌丝体生长，菌丝体干重最大。云芝葡聚糖对PVY的抗性试验表明：提前施用云芝葡聚糖对PVY有很强的预防作用，预防效果达73.98%，对PVY有一定的钝化、抑制增殖作用，700μg/mL云芝葡聚糖对PVY的钝化效果为28.79%，对PVY增殖抑制率达40.25%；能诱导植株抗性，700μg/mL云芝葡聚糖处理，诱导烟草的抗性，对PVY的抑制率为59.84%。室内盆栽试验表明云芝葡聚糖对寄主表现出很强的保护活性，保护效果优于治疗效果，接种病毒14d后云芝葡聚糖300倍液的保护和治疗效果最高，分别为73.33%、38.46%，明显高于对照药剂氨基寡糖素水剂和香菇多糖水剂的防效。云芝葡聚糖对烟草防御酶活性影响试验结果表明：可显著诱导烟草防御酶的活性，500μg/mL云芝多糖处理及喷药处理后接种PVY的烟草叶片POD和PAL酶活性均较清水处理、喷清水后接PVY处理有不同程度的提高。研究得出结论：云芝葡聚糖是一种很强的免疫增强剂，对PVY的抑制作用显著，提前施用可达到很好的保护作用。更多还原

【Abstract】 Potato virus Y (PVY) is a kind of worldwide virus, sympotoms(Mosaic,deformity, dwarf, peeling) are caused by infecting tobacco (Nicotiana tabacum),potato (Solanum tuberosum), pepper (Capsicum SPP.), tomato (S.lycopersicum) andso on, the yield and quality of tobacco leaves has been influenced seriously bycausing veins necrosis in tobacco leaf.We have determined the antiviral activities of12kinds of fungipolysaccharide,We discovered versicolor polysaccharide have strong immuneenhancement effect,the application of versicolor polysaccharide can prevent theinfection of TMV and CMV, also improve the quality and production oftobacco.However, the extraction process of Trametes Versicolor polysaccharide stillexists fautiness, its resistance to PVY is unclear.To optimize the extraction process,the optimized methods were explored byselecting better versicolor strain, comparing the extraction methods between hot waterextraction and ultrasonic extraction, optimizing the mycelium fermentation conditions(medium composition, fluid volume, time).To provide the basis for the developmentand application of new fungicide-Trametes Versicolor polysaccharides, the anti-PVYactivity of Trametes Versicolor polysaccharides were explored. The inducibleresistance and the effect on the activity of defensive enzyme was determinated.The effect of prevention and deactivation on PVY were detected by half leafmethod on Chenopodium amaranticolor and the inhibition of replication by Leafdiscs method on Nicotiana glutinosa，the control effect to PVY was tested by potexperiment.It was confirmed that the mycelium growth of YZ-1is faster than YZ-2,the yieldof polysaccharide is higher, it’s much more time-saving and efficient for ultrasonicextraction, the optimum fermentation conditions for mycelium growth is85mL fluidvolume in number3culture medium for7days, in this condition,the dry weight ofmycelium is the largest.The Versicolor polysaccharide has a strong preventive effect to PVY, thepreventive effect reaches73.98%. The inactivation effect was28.79%and theinhibition rate of multiplication reaches40.25%after being treated by700μg/mLTrametes Versicolor polysaccharide. Treated by polysaccharides can induce theresistance of host, the inhibition rate was59.84%,also increase the activity of tobacco defense enzymes than the contrast. The potted experiment showed that TrametesVersicolor polysaccharide has evident protective activity,14days after inoculatingPVY, the protective effect and therapeutic effect of polysaccharide300×wererespectively73.33%、52.38%, higher than the contrast.These results indicated that Trametes versicolor polysaccharides is animmunopotentiator and has a strong inhibitory action to PVY, application in advancecan achieve better protection effect.更多还原