RSV(Rice stripe virus)is a kind of viral disease transmitted by Laodelphax striatellus(LS).Once paddy rice infected with the virus,it is difficult to control the disease which would cause great loss of rice production.In recent years,as the cropping system changed and climatic conditions suited,the trend of Rice stripe virus RSV disease tend to go up acutely in north part of Zhejiang,especially in Jiaxing and Huzhou.The two cities became the most severe area Rice stripe virus RSV occurred.The RSV forecasting and prediction was the foundation to control and prevent the disease.From 2005 to 2007,we selected the key predict factors based on the study of RSV occurrence patterns established forecasting model and predicted the disease successfully in 2006 and 2007.The integrated results reorganized as following:In the observation area,investigate the quantity of LS in wheat field,the seedling field time and rice growth stage,analysis the RSV disease rate under the conditions of different pest amount.Determine the disease rate of the winter generation of LS with quick-detection method and biological assay,compare the conversion relation between the two methods,and investigate the disease condition in the steady-going periods,analysis the relation between the carrier rate and the occurrence of the disease.Sow the seeds in four stages equally in 2006 and 2007,the sowing time respectively be May 15,on May 22,on May 29 and on June 5.There is 7-days interval between every two stages,duplicates 3 times in each stage,and the field area is 333m2in each plot.Sow the seeds by stages,transplant the seedling in turn when they are 30-days-growing periods.In the steady disease occurring time,investigate cluster disease incidence and individual disease incidence,analysis the influence of sowing time did on RSV.In the steady disease occurring time,do a large-area survey of RSV disease on the main paddy rice variety in the whole city,observes the anti-(bears)degree of each variety to RSV.Collect historical materials including cultivation,planting,variety and meteorology,analysis the relations between them and the plant disease.Use has gradually regression and simulating model methods to set up forecasting model,and predict the disease trend.2.1.1 The carrier rate of LS In 2005,2006 and 2007 we determined the carrier rate of LS by biological assay in Xiuzhou area,the city of Jiaxing,Zhejiang province.The results were 0.0%,2.01%and 2.69%respectively.We had a survey in the unprevented field in the steady disease occurring time in the middle ten days of July,and the result showed that disease conditions among the fields were remarkably different.The carrier rate could not be tested in 2005,so the disease was not serious and the average diseased cluster rates of early planting field,middle time planting field,late planting field were 3.1%,1.2%and 0.0%respectively.The disease aggravated in 2006,the carrier rate increased to 2.01%and the average diseased cluster rates of early planting field,middle time planting field,late planting field were 18.5%,10.1%and 1.2%respectively.When the carrier rate was 2.69%,the disease continually aggravated and the average diseased cluster rates of early planting field,middle time planting field,late planting field were 21.5%,16.5%and 1.5%respectively.It showed that the carrier rate affected the prevalence of disease directly,and the relationship between the two was very close.The higher the carrier rate was,the greater the disease incidence would be,instead the disease incidence lighter.According to the Japanese experience,when the carrier rate(qick-detection method)is more than 3%,the prevalence of RSV is more likely to happen.If the carrier rate ＞12%,there would be a seriously epidemic trend.According to the comparison of carrier rate and biological assay in recent years,the results tested by the two methods were different.The result of biological assay was significantly lower than that qick-detection method,and the ratio was about 1:1.75.Therefore,we chosed biological assay for prediction.When the carrier rate ＞1.71%,the disease had moderate trend,when the carrier rate ＞6.86%,there was a pandemic disease trend.YearInfestingnymphes(%)Infestedhill(%)EarlysowingMidsowingLattersowing20050.003.11.20.020062.0118.510.11.220072.6921.516.51.5Table 1 The relatonship between the rate of viruliferous LS and the ccurrence of Rice stripe virus RSV (Xiuzhou Jiaxing,2005～2007)2.1.2 Amount of LS Under certain conditions of carrier rate,amount of LS is an important factor to determine whether the RSV would be prevail or not.The higher the volume of insects was,the greater the incidence was,instead the incidence lighter.In recent years,amount of LS continued increase.In years 2005,2006,2007,the amount of first generation LS per 667m2 in wheat field reached 2.98 million,2.877 million and 4.093 million.LS transferred to the nearby weeds or other crops after the wheat harvest.They moved to the seedling when rice is planting and caused RSV occurring.It has been observed that the first peak incidence(7/early) caused by the first genenration LS generation was more serious than the second peak incidence(8/early)caused by the second generation insect,because the first generation LS had a large amount a high rate of virus spreading.But as the second generation LS lived in high-temperature season,the insect amount of was small and rate of virus spreading was low,so the disease was lighter.2.1.3 Sowing date of paddy rice Paddy rice sowing date is an important factor to influence RSV.The incidence would be heavier when the sowing time was sooner,otherwise the incidence was lighter or even not onset.We had a investigation in a stable condition period(mid-July)among different rice sowing time in years 2005~2007,and found that sowing time were closely related to the occurrence of diseases.For example,in accordance with the four sowing times in 2006,the cluster disease rates were 18.5%,10.0%,5.67%and 1.5%in turn,the individual disease rates were 4.07%,2.69%,1.89%and 0.42%in turn.With the sowing time delayed,the disease lightened.Among the four sowing times in 2007,disease in early planting field was the most serious,the cluster disease rates were 16.2%and 16.67%respectively,the individual disease rates were 5.18%and 7.31%respectively.Disease in late planting field was light,the cluster disease rates were 2.7%and 1.5%respectively,the individual disease rates were 1.9%and 0.7%respectively.YearSowingdateInfestedhill(%)Infestedplant(%)Dup1Dup2Dup3Aver0.050.01Dup1Dup2Dup3Aver0.050.01200620075/1517.516.521.518.50aA4.163.164.884.07aA5/2210.510.59.010.00bB2.553.332.182.69bAB5/296.04.56.55.67cC2.021.072.571.89bBC6/52.00.52.01.50dD0.630.130.500.42cC5/1516.017.015.516.20aA6.225.214.115.18aA5/2218.015.516.516.67aA9.315.826.807.31aA5/293.03.02.02.70bB2.472.350.891.90bB6/52.01.01.51.50bB0.770.680.640.70bBTable 2 RSV occurrence in different sowing date (Nanhu Jiaxing,2006～2007)2.1.4 Cultivation and planting system In recent years,the wheat area has expanded,which wasconducive to the survival and reproduction of the overwintering generation and first generation LS.A wide range of weeds in the field create good conditions for the insects to transit to the rice.According to the observation in 2006,that disease rates of all rice seedling fields near the wheat field was evidently higher than fields away from the wheat field.In the directseeding fields,disease rates in the verge was evidently higher than that in the medial part of the field.As a result of the sowing time was early in the transplanting field,the seedlings were easily infected by massive LS and the disease arised heavily.2.1.5 Paddy rice varieties There are certain differences among different varieties of RSV,generally,disease of sticky rice was heavier than late rice,disease of hybrid Japonica ricewas heavier than ordinary late rice,disease of Late japonica rice was heavier than mid japonica rice,desease of indica rice was lighter.Speaking of the present Zhejiang Jiaxing paddy rice,the disease resistance of the main varieties are all poor. A general disease survey in 2006 showed that the disease of Show You No.5 was the heaviest,incidences of Xiushui 09,Xiushui 110,Jiahua No.1 and Jia 991 were also heavier,Jialeyou 2 was lighter,see Table 3.VarietyInfestedplotsInfestedplantInvest.plotsInfestedplotsRate%Infestedplant%Range%Xiusui09391743.61.290~6.23Xiusui11018738.91.130~4.15Jiahua1261038.50.890~4.36Jia99112866.71.520~7.32Xiuyou510990.03.780~11.20Jialeyou29333.30.310~3.11Table 3 The resistance of rice variety to RSV (Jiaxing, 2006)2.1.6 Climatic conditions Winter temperatures directly influence overwinter LS According to information from meteorological departments in Jiaxing City:the average temperature in February-March in 2007 was 10.2°C,1.8℃higher than the same period in 2006,3.6°C higher than 2005.Because the winter temperature continued high,the survival rates of winter generation LS is high and quantity of insect was large.The quantity of overwintering insects was significantly higher than that of 2006,but in 2006 the quantity was higher than that in 2005.The three-body interaction among virus source,media and susceptible.Varieties was the important factor in the prevalence of RSV.Based on the carrier rate and RSV disease rate in the virus-transmitting period,or the relation between the early and late disease rate,key predictors was screened and a forecasting model was established as following:Y=1.6893X-1.6935X-carrier rate of LS,Y-RSV disease rate.There were many key factors which were conducive to the transition and migration of LS,for example,a higher carrier rate,a large amount of LS,the poor resistance of the main variety,the coincidence of rice-sowing time with the first adult generation insect virus-transmitting peak,the expanding wheat area a wide range of weeds in the fields and so on.In 2006,we had a comprehensive analysis of these key factors,predicted RSV trend quantitatively with forecasting model on May,18.It predicted that RSV disease would be moderate biased towards popular while measured result was moderate pandemic,the incidence area of the whole city was up to 15500 hectares.Compared to the previous year,the carrier rate in 2007 declined slightly,but the quantity of LS increased largely,and the other factors did not change significantly.We had a comprehensive analysis over such factors and predicted RSV disease trend with the forecasting model in April,26.We predicted the RSV disease would be moderately popular in our city and measured moderate pandemic,the incidence area was 16400 hectares.Two years application of forecast indicated that the forecasting time could be earlier if we used this forecasting model and predictors to analysis and forecasting the trend of RSV disease.We can make out accurate prediction in late April and before late May.The predictions above were generally in line with the actual results and provided a scientific basis for"pest control and disease prevention".Using methods of the system investigation and stepwise regression analysis,we screened primary predictors including carrier rate,the LS insect quantity,paddy rice varieties and sowing time,cropping and cultivation system and meteorological forecasting factor.Among these factors,the carrier rate(X)related to the individual rice disease rate(Y)most closely.We established the following forecasting model:Y=1.6893X-1.6935.Using this model and predict factor-integrated analysis,the mid-long period trend of RSV in 2006 and 2007 in Jiaxing City,Zhejiang was predicted and was generally in line with the actual results.The prediction provided a scientific basis for decision making of disease control and the production application has obtained obvious socio-economic and ecology benefits.

水稻条纹叶枯病是由灰飞虱传播的发生严重的病毒病，近年来，在浙江北部稻区呈快速蔓延扩大趋势，对水稻安全生产构成极大威胁。为了调查测定水稻条纹叶枯病为害与损失，为制订防治指标提供科学依据，2005～2006年我们在浙江嘉兴对水稻条纹叶枯病为害损失进行较为系统的测定，现将结果综合整理如下：单季晚稻，秀水09。在4月下旬采用生物法测定当地灰飞虱带毒率。自5月15日播种后，每隔3～5天调查秧田期灰飞虱虫口密度；6月15日移栽后，每隔5天调查本田初期灰飞虱密度，于发病后（6月下旬）开始每隔3～5天定点调查水稻丛发病率、株发病率。于病情稳定后（8月15日），根据田间自然发病情况，选取不同发病率（形成发病梯度）的点59个，每个点抽查20丛（200株），调查株发病率，待水稻成熟后单丛考种测产。据生物法测定，灰飞虱带毒率为2.01%。5月中下旬调查，秧田期灰飞虱虫量平均每平方米213头，推算带毒虫量平均每平方米为4.473头。本田期病情稳定期调查，水稻株发病率平均为4.88%，二者之比为1：1.091，见表1、表2。调查日期（月/日）成虫数（头/m2）若虫数（头/m2）合计虫量（头/m2）折合667m2（亩）虫量（万头）5/207070.46675/23193221.46675/26292312.06675/29815865.73346/4145915410.26676/81961721314.20016/121842420813.86676/151653920413.6001表1 秧田期灰飞虱虫量调查（浙江嘉兴，2006）调查日期（月/日）定点丛数调查株数发病丛数发病株数丛病率（%）株病率（%）6/2020062000006/2420086000006/28200136015197.51.46/3020013602429122.17/320018603241162.27/520019003692184.847/720019003692184.847/10200205040100204.887/1720021804310221.54.65/152002180399719.54.45表2 本田期条纹叶枯发病的系统调查（浙江嘉兴，2006）水稻条纹叶枯病株发病与产量损失率关系测定结果，平均株发病率为0.5%～11.5%，产量损失率为0.33%～9.02%。株发病率与产量损失率二者之比为1：0.576～1.01，平均为1：0.792，见表3。随着水稻发病株率（X）上升，产量损失率（Y）加大，两者具密切的相关性，建立的关系式为：Y=0.4768+0.7276X，r=0.8898**。株发病率（%）水稻200穗产量（g）产量损失率（%）株病率与损失率之比0.0（对照）524.20.5522.50.330.661.0518.91.011.011.5518.11.160.7732.0514.71.820.912.5616.61.440.5763.0509.72.760.923.5508.92.910.8314.0507.343.210.8034.5504.63.730.8295.0504.73.730.7465.5501.64.320.7856.0502.04.240.7076.5501.74.290.667.0493.55.870.8397.5490.06.520.8698.0488.66.800.858.5489.26.670.7859.0490.46.460.71810.0483.67.750.77511.5476.99.020.784对照（0.0）524.2表3 水稻条纹叶枯病发病率与水稻产量损失率测定（浙江嘉兴，2005～2006）大田调查测定结果表明，水稻条纹叶枯病发生与灰飞虱虫口密度高低和带毒率具有密切相关性，随着灰飞虱虫口密度提高，为害程度上升，产量损失率加大，建立了为害损失关系式。条纹叶枯病发病株率与产量损失率之比，2年测定结果为1：0.576～1.01，平均为1：0.792。田间调查表明，水稻条纹叶枯病发病后，前期稻苗大多枯死，对产量损失大。该调查结果为条纹叶枯病发病为害损失评估，制订防治指标提供科学依据。

苹果锈病在冀北地区历年来均属零星发生，但近2年来在部分果园突然开始大发生，其中，2007年部分果园发病株率达到100%、病叶率90%以上，苹果产量和质量急剧下降，经济效益损失接近100%。笔者于2007年对冀北地区苹果主产地的宽城、兴隆、承德等县的苹果园进行了系统调查，发现苹果锈病在该地区普遍发生，给当地苹果生产造成了较大损失。苹果锈病又名赤星病、羊胡子，有的地区俗称黄斑病、长毛病。该病可为害叶片、新梢、果实，叶片先出现橙黄色、油亮的小圆点，后扩展，中央色深，并长出许多小黑点（性孢子器），溢出透明液滴（性孢子液），此后液滴干燥，性孢子变黑，病部组织增厚、肿胀（也就是群众所称的叶子上长了黄疙瘩），病斑多呈纺锤形，以后叶背面或果实病斑四周，逐渐长出黄褐色丛毛状物（锈孢子器，即群众所称的长胡子、长毛毛），内含大量褐色粉末（锈孢子）；果实发病，多在萼洼附近出现橙黄色圆斑，直径10mm左右，后变褐色，病果生长停滞，病部坚硬，多呈畸形。苹果锈病病原菌（Gymnosporangium yamadai Mouabe）称山田胶锈菌或苹果东方胶锈菌，属担子菌亚门真菌。该菌是转主寄生菌，在苹果、梨树上形成性孢子和冬孢子，在桧柏上形成冬孢子，以后萌发产生担孢子[1]。转主寄主主要是桧柏，其次是括高塔柏、新疆圆柏、欧洲刺柏、翠柏、龙柏等[2]。该病每年只侵染1次，病菌以菌丝体在桧柏类植物上越冬，翌年春天在桧柏上形成冬孢子角，冬孢子角内的胶状物质遇雨吸水膨胀，其中的冬孢子产生大量的担孢子。担孢子不能侵染桧柏，而是随气流传到苹果树上，致使苹果树发病，开始在叶片正面出现性孢子器，以后在叶背面出现锈孢子器，产生的锈孢子再随气流传到桧柏上为害、越冬，从而完成一个侵染循环。从苹果锈病的侵染循环可以看出，如果没有桧柏类植物，苹果锈病就不能完成侵染循环，也就不能发生。据有关资料[3]介绍，桧柏类植物上的担孢子传播距离一般为2.5～5km，最远50 km。因此，苹果锈病的发生与否或发生轻重主要决定于周围5 km有无桧柏等转主寄主的存在。该病作为初侵染源的冬孢子角的萌发和冬孢子、锈孢子的侵染都需要适当降雨和相对湿度大于90%的条件。因此，该病的发生轻重和早晚与春季降雨早晚和雨量大小关系密切，降雨早则发病早，雨量大则发病重。据笔者调查，在冀北地区，一般春季4月下旬至5月上中旬降雨量达到15mm以上时，桧柏类植物上的菌瘿开始迅速吸水膨大，形成花瓣状的冬孢子角，冬孢子随即萌发形成担孢子，随气流传播至苹果树染病，一般从5月下旬叶片正面开始出现病斑，6月上旬大量发病，至8月份叶背面开始出现锈孢子器。冀北地区农村历来有翠柏栽植，但一般都长在较偏僻的陡峭山上，距离苹果园较远，而桧柏只是在城镇有少量栽植，即使偶尔有苹果锈病的担孢子飞散传播，数量也相当少。因此，该地区苹果锈病历年均零星发生或不发生，果农对该病也比较陌生。近3年来，各地大搞文明生态村建设，为了绿化和美化农村环境，开始在农村的路边、房前屋后、群众休闲活动广场等地大量栽植桧柏类植物，这些地点一般距离苹果园较近，给苹果锈病完成侵染循环提供了充分的条件，致使这些地区苹果锈病在2007年偏重发生或大发生。据笔者对冀北地区6个距离桧柏不同远近的果园调查，凡是附近栽植桧柏的果园，苹果锈病就发生重，反之则发生轻。一般建在路边距离桧柏近的果园，苹果锈病发生重，建在山坡上距离桧柏相对较远的果园则发生轻，而发生程度与距离桧柏远近呈明显的正相关。从表1可以看出，与桧柏距离50m以内的苹果树，全部感染苹果锈病，病叶达到90%以上，每个病叶上平均有病斑3.7个；与桧柏距离80～120m的苹果树，全部感染苹果锈病，病叶率略有下降，但仍达到70%左右，每个病叶上平均有病斑2.3个；与桧柏距离180～230m的苹果树，全部感染苹果锈病，病叶率为20%左右，每个病叶上平均有病斑1.6个；与桧柏距离500～630m的苹果树，病株率为58.5%，病叶率10%左右，每个病叶上平均有病斑1.15个；与桧柏距离2100～2250m的苹果树，感染率为20%左右，病叶率仅为1.2%，每个病叶上仅有1个病斑；与桧柏距离5100～5200m的苹果树，感染率急剧下降，仅为4.5%，病叶率仅为0.2%，每个病叶上仅有1个病斑。与桧柏距离（m）50以内80～120180～230500～6302100～22505100～5200病株率（%）100.0100.0100.058.519.64.5病叶率（%）91.571.622.610.51.20.2平均百叶病斑数336.2166.736.512.11.20.2表1 苹果锈病的发生程度与距离桧柏的远近关系调查表（2007年6月14日，河北宽城）苹果锈病虽然不是冀北地区果园新发病害，但是由于其具有需转主寄主才能完成侵染循环的特性，发生极少，不如腐烂病、斑点落叶病、轮纹病等常发病害那样清楚，绝大多数果农根本不认识，因此预防意识淡薄，盲目引进了桧柏类植物，而在春季又没有对其进行防范措施，导致了该病的重发生。切断苹果锈病的侵染循环是防治该病最有效的手段，新建果园时，应当远离桧柏、翠柏、龙柏类植物5km以上，对于5km之内已有桧柏等植物的，有条件的建议彻底清除。对于彻底清除5km之内桧柏等植物有难度的果园，必须采取综合措施控制冬孢子萌发。第一，可以在早春苹果萌芽前，剪除桧柏类植物上的菌瘿并集中烧毁或喷药抑制冬孢子萌发；第二，可以喷药清除菌源。应根据天气情况，在苹果萌芽期至幼果拇指大小时，尤其是4月下旬至5月上中旬遇有15mm以上且持续时间较长的降雨时，必须及时在桧柏类植物上及时喷洒波美3度的石硫合剂或三唑酮等药剂，清除越冬病菌；第三，苹果锈病发生重的果园，还应在秋季喷药保护桧柏类植物，防治锈病侵染。对于附近有桧柏类植物的果园，除了清除转主寄主的菌源以外，还应对果树进行树上喷药保护，一般在苹果花芽露红和落花后各施一次药，发病严重的还应在落花后10～15天施第三次药。常用的药剂有：15%三唑酮可湿性粉剂1500～2000倍液、12%烯唑醇可湿性粉剂2000～2500倍液、43%戊唑醇（好力克）悬浮剂3000～4000倍液、25%戊唑醇（富力库）水乳剂1000～2000倍液、25%丙环唑（敌力脱）乳油1000～4000倍液、40%氟硅唑（杜邦福星）乳油8000倍液等。苹果锈病的担孢子可飞散传播5km以上，但由于冀北地区属山区，自然屏障较多，因此，以200m以内传染为害较重，如菌量充足，可使该范围内绝大多数苹果树发病，对产量影响极大，200～500m之间发生程度中等；距离转主寄主5km以上的苹果树虽然也可以发病，但发病率较低，对产量一般不会造成严重损失。切断侵染循环是防治苹果锈病的根本所在，而喷施药剂是防治该病的重要措施。

玉米矮花叶病（Maize Dwarf Mosaic）和玉米粗缩病（Maize Rough Dwarf）是近十几年来为害我国玉米生产的两种主要病毒病害[1]。自20世纪90年代以来，玉米矮花叶病、粗缩病在山西流行严重[1，2，5]，给玉米生产带来很大损失，特别是1994～2000年连续严重发生的玉米矮花叶病和粗缩病，使山西省运城、临汾等地的晚播玉米颗粒无收，夏玉米因病害减产30%以上[2]。1998年全省发病面积45万hm2，占玉米种植面积的52%，全省损失粮食5亿多kg[3]。大面积种植感病品种是病害流行的重要原因。改良山西省常用玉米自交系和杂交种对病毒病的抗性，已成为玉米生产和育种单位急待解决的问题[3，7]。国内外研究表明：不同的玉米自交系和杂交种对玉米病毒病的抗性有明显差异[4]。选育和种植抗病品种是防治玉米矮花叶病和粗缩病最经济有效的措施[3，6，7]。本研究皆在通过田间自然发病初选，人工接种，病圃重复鉴定，筛选出对两种玉米病毒病具有抗性的种质资源。为有效地开展玉米抗病毒病育种提供参考依据。供试玉米种质资源材料共915份，其中常用玉米自交系276份，杂交种及新组合181份，热带改良新选系458份。热带改良新选系由本所种质改良课题组提供，其余的玉米资源由省内有关育种单位和种子公司提供。1.2.1 田间自然发病鉴定初选 田间自然发病鉴定初选：2001年和2002年对全部材料分2年在山西省玉米病毒病发生严重的地区运城、临汾和太谷3个点同时进行。每份材料种植2行，每行50株，行长15m，株行距0.3m×0.65m。以自然发病为主，授粉1～2周后调查病株率，发病率在15%以上的视为不抗病。对这批材料将不进行抗病复选。1.2.2 人工接种重复鉴定复选 2003～2004年，对经过田间初选的抗病材料同时进行矮花叶病人工接种和粗缩病自然重复鉴定。病圃设在山西省农业科学院小麦研究所实验场（临汾市区），历年发病较重的固定地块。供试材料田间顺序排列，每份材料种植2行，每行25株，行长7.5m，株行距0.3m×0.6m。玉米矮花叶病人工接种方法：采用蚜虫接种法，设自交系黄早4（R），Mo17（S）为抗、感对照种。玉米粗缩病重复鉴定方法：采用田间自然接种法，鉴定圃四周全部种植冬麦，利用灰飞虱发生规律，调节玉米播期（5月中旬）使幼苗与成虫羽化高峰期吻合，以达到传毒最佳效果，设自交系沈137（R），478（S）为抗、感对照品种。玉米授粉半个月后调查病情。玉米矮花叶病病株分级标准参照吴全安的方法[11]。即：0级全株无症状；1级，植株上部叶片1%～3%显症，有褪绿斑花叶；2级，植株中部叶片，1%～30%显症，植株略矮；3级，植株严重发病，2/3的叶片呈现花斑条纹，果穗弯小或不结实。病情指数按以下公式计算：依据病情指数划分抗病类型，0～5.0高抗（HR）；5.1～15.0抗病（R）；15.1～30.0中抗（MR）；30.0以上感病（S）。玉米粗缩病病害分级标准参照陈巽珍分级标准[8]，即：0级，健株，全株无症状；1级，比健株矮1/5，雄穗轴稍短；2级，比健株矮1/2，顶部略丛生，果穗长度为健株的1/2；3级，株高为健株的1/3，顶部叶小，上冲，穗小多畸形；4级，苗株死亡或极矮小，顶叶上冲丛生，绝收。病情指数计算公式同前。依据病情指数，划分抗病类型，0～5.0高抗（HR）；5.1～20.0抗（R）；20.1～40.0感（S）；40.1以上高感（HS）。2001～2002年，对915份玉米自交系和杂交种在重病区进了田间自然发病鉴定初选，淘汰了感病材料208份。2002～2004年，对初选的912份材料（自交系537份，杂交种142个），进行了矮花叶病、粗缩病人工接种，病圃重复鉴定。鉴定筛选结果见表1、表2和表3。种质类型Germplasmtype鉴定数量No高抗highResistant抗Resistant感Susceptible高感HighsusceptibleNo%No%No%No%自交系Inbredlines734253.411816.125334.533846.0杂交种Hybrids181168.96938.15832.03821.0合计Total915414.518720.431134.037641.1Table 1 Results of indentification for resistance of maize inbred lines and hybrids to SCMV-MDB种质类型Germplasmtype鉴定数量No高抗highResistant抗Resistant感Susceptible高感HighsusceptibleNo%No%No%No%自交系Inbredlines734334.512917.634547.022730.9杂交种Hybrids1812916.05128.26636.53619.9合计Total915626.817919.641144.926328.7Table 2 Results of indentification for resistance of Maize inbred lines and hybrids to MRDV种质类型Germplasmtype鉴定数量No双高抗双抗DoublehighNoResistant%DoubleNoResistant%自交系Inbredlines73470.967510.2杂交种Hybrids18195.05027.6合计Total915161.7512613.8Table 3 Results of indentification for resistance of Maize inbred lines and hybrids to SCMV-MDB and MRDV表1表明经过人工接病鉴定：筛选出抗矮花叶病自交系118份，占自交系鉴定总数的16.1%，杂交组合69个，占杂交种鉴定总数的38.1%，优良高抗病自交系有25份，占自交系鉴定总数的3.4%，它们是：选9、齐31、93选2、假B734、选78、选7、选141、选127、选301、选145、选151、选250、5081、改84-2、改99-1、改100-1、改113-1、改100-2、改474-1、改418-1、改377、改403、改426、沈137、99-5。表现为高抗病的杂交种有16个，占杂交种鉴定总数的8.9%，它们是：长单39、长单40、忻抗7号、太早单18号、98-1×5081、并单3号、齐319×98-3、并单4号、422×齐35、B734×93选2、H9-21×临京11-2、农大108、忻玉106、忻单108、晋单36、鲁单50。表2结果表明：供鉴定材料中，抗粗缩病自交系有129份，占自交系鉴定总数的17.6%；杂交种50份，占杂交种鉴定总数的27.6%；高抗病自交系有33份，占自交系鉴定总数的4.5%。它们是：选29、选41、选114、选125、选214、齐31、齐35、93选2、假B734、选331、选78、选184、选159、R选3、选50、选59、选2-2、选11-1、选46-2、选121-1、选132-1、选155-1、R10-2、R49-1、选90-3、海选36、改357-1、改474-1、改418、改408、改427、98-2、98-3。高抗病杂交种29个，占杂交种鉴定总数的16.0%，它们是：B734×93选2、422×齐35、并单4号、陕单971、新陕单1号、鉴35、齐31×98-3、并单3号、陕高农5号、临油1号、忻玉106、长单40、屯9902、同单4号、同早5号、春早单3号、运早1号、FL2、晋玉681、早利26、京单958、太早单20、太早单21、早玉2号、早玉4号、LD981、运单14、H9-2×临京11-2、H9-2×临京11-3。通过表3可以看出：被鉴定材料中，对两种病毒病同时都表现为抗病的自交系有75份，占自交系鉴定总数的11.6%，如：选41、选125、选214、齐35、选331选159、选50、选7、选141、选31、选211、选87、选14、选217、选301、选186、选102、选145、选151、选153、选250、改2-2、改11-1、改132-1、改155-1、R49-1、选90-3、海选36、改15-2、改16-2、改29-2、改50-2、改99-1、改100-1、改102-2、改111-2、改113-1、改116-1、改125-1、改134-2、改170-2、改357-1、改474-1、改418、改408、改427、改377、改403、改426、改404、改476、改406、改407、改416、改419-1、改420、改422、改430、改432、改433、改440等。双抗杂交种51个，占杂交种鉴定总数的29.8%，如：陕单971、新陕资1号、鉴35、陕单931、98-1×5081、4-18、临油1号、忻玉106、选66×308-2、忻5344、忻玉105、长单39、屯单9901、屯9902、屯9906、京玉8号、春早单1号、春早3号、太单早18、太单23、太单32、早利26、协玉2号、运单13号、晋玉681、晋玉751、科试7号、沈单10号、早玉3号、早玉2号、并单1号、太早单20、高油115、忻玉9704、忻抗13、LD981、DH3801、强盛17、并单2号、同单36号等。对两种病毒病同时都表现为高抗的材料共16份，占鉴定总数的1.96%，其中双高抗自交系有选29、齐31、93选2、假B734、选78、改474-1、改418，共7份，占自交系鉴定总数的1.1%。双高抗病杂交种有B734×93选2、422×齐35、并单4号、齐31×98-3、并单3号、陕高农5号、长单40号、H9-21×临京11-2、忻玉106，共计9个，占杂交种鉴定总数的5.3%。杂交种抗矮花叶病的比例为38.1%，自交系的为16.1%；杂交种抗粗缩病的比例为28.2%，自交系的为17.6%；杂交种同时抗这两种病毒病的比例为27.6%，自交系的为10.2%；杂交种同时高抗这两种病毒病的比例为5.0%，自交系的为0.96%；通过对杂交种和自交系材料抗病性比较，可以看出杂交种抗病的比例远高于自交系的。从表4看出被鉴定热带亚热带玉米改良自交系中，对两种病毒病同时都表现为抗病的有59份，占热带改良系鉴定总数的12.9%；对两种病毒病同时都表现为高抗的有5份，占热带改良系鉴定总数的1.1%。而国内温带自交系对两种病毒病同时都表现为抗病的有16份，占国内温带自交系鉴定总数的5.8%；对两种病毒病同时都表现为高抗的仅2份，占国内温带自交系鉴定总数的0.7%。从而可以看出热带亚热带玉米改良自交系抗病比例远远大于国内温带系。种质类型Germplasmtype鉴定数量No双高抗双抗DoublehighNoResistant%DoubleNoResistant%自交系Inbredlines73470.967510.2热带改良系Tropicalinbredlines45851.15912.9国内温带系Chinatemperate'sinbredlines27620.7165.8Table 4 Results of indentification for resistance of Tropical and China temperate's inbred lines to SCMV-MDB and MRDV采用蚜虫接种法，重病区病圃自然发病重复鉴定法，4年来，对816份不同类型玉米种质资源进行了玉米矮花叶病、粗缩病的抗病性鉴定。筛选出同时抗两种病毒病的自交材料75份，杂交种51个；双高抗病优良自交系7份；双高抗病杂交种9个；为玉米抗病毒病育种提供了一批抗病材料，为玉米生产上应用抗病品种提供了科学依据。在鉴定材料中双抗病材料所占比例较小，同时高抗两种病毒病的材料所占比例更小，鉴定材料的抗病性与其来源关系密切，不同的种质材料对两种玉米病毒病的抗病性有明显差异，杂交种和杂交组合的抗病性比例明显优于自交系；不同来源自交系的抗病性差异更大。利用热带、亚热带玉米种质改良的新选自交系，抗病比例远远高于没有热带血缘的常规系，这说明热带、亚热带玉米种质资源中有优良的抗病毒病基因，是改良我国温带玉米种质病毒病抗性的很有利用前景的抗源种质。本研究采用的矮花叶病蚜虫接种法，是我国多年来传统接种的方法，虽然由于养蚜、饲毒等工作量较大，但不失为一种可靠性强的接种方法。粗缩病的抗性鉴定方法国内现在一直采用田间自然发病鉴定方法，试验选择了利于病毒病发生的试验环境，把鉴定点设在山西省发病严重的地块进行，并进行了重复鉴定，使鉴定结果有了更强的可靠性。

The small brown planthopper,Laodelphax striatellus Fallen(Homoptera:Delphacidae)is a widely geographical distributed planthopper in the Euro-Asian continents(Zhu et al.2005).It is the vector of the rice stripe disease caused by the rice stripe virus(RSV).RSV has been a destructive rice disease in the Eastern Asian countries(Hibino,1996;Cheng et al.2002;Zhu et al.2005;Zhu et al.2007).The transmission process and efficiency of a plant virus by their vectors was influenced by many factors(Gray&Banejee,1999),for instance,environmental temperature,plant species(Jin et al.1985),plant age(Wang et al.2007),but no information was documented on the role of the planthopper vector's age on the rice stripe virus.In the year 2006 and 2007,we collected nymphs and adults of the vector planthoppers from overwintering habits and biologically tested their transmission rates.In 2006,the small planthoppers in growth stages of large nymphs and macropterous and brachypterous adults were collected from overwintering habits such wheat,barley,rye fields and grasses in bank fields of 5 sites,e.g.Haiyan,Haining,Jiashan,Huzhou and Changxin,Northern Zhejiang Province.In 2007,the vectors were collected from 7 sites,e.g.Haiyan,Haining,Xiuzhou,Jiashan,Tongxiang and Changxin.More than 100 planthoppers were collected from each site each year.2.2 Rice seedlingThe most widely grown rice cultivar Xiushui 110,a Japonica type bred by Jiaxing Academy of Agricultural Sciences,was sown and maintained in greenhouse plots and the seedlings at age of 15 days were used for the bioassay.After they were collected and transported in healthy rice seedlings to the laboratory,the planthoppers were separated into groups of larger nymphs,macropterous and brachypterous adults as described in Sun et al.(2007).One rice seedling was set in a glass tube in size of 15cm×2cm and enclosed in one end with nylon mesh.After one planthopper of either nymph or adult was put into each glass tube,the second end was enclosed as for other the end and the glass tubes were marked for the vector's site etc.All the tubes and plants with planthoppers were sitting vertically on trays with still water to maintain the plants alive.The trays were kept in a greenhouse of RH75%,25～28℃ with 14L:10D.After 24 hours after infection,the seedlings were transplanted into plots in a screen house and covered by net cages in size of 30 cm in height×10cm in diameter individually.The seedlings were monitored and recorded daily for the incidence of the rice stripe disease till 30 days.Since all the incidence data of percentages of infected rice plants were lying within the range of 0 to 30%,the square-root transformation was used before analysis of variance.The Generic linear model(GLM)was applied to separate the factors and their interactions on the variance.Thereafter,the least significant difference(LSD)was used to compare the difference among the transmission rates of different status of vectors.The data analysis was performed in the DPS program(Tang and Feng 2006).The age and site of the vector had significant effect on the transmission rate(ANOVA,F(2,32)=82.85,P=0.0001;and F(6,32)=8.54,P=0.0098,Table 1),but the factor of year and the two-paired interactions among all the three factors were not significant(P>0.05,Table 1).This indicates that transmission competencies of the vectors collected from different sites were consistent over these two years.In both the years of 2006 and 2007 for each site,the transmission rate of large nymph was higher than those of brachypter and macropter,respectively,and the mean of the former was significantly higher than those of later(Table 2).The ratio of such transmission rates was nymph:macropter:brachypter=1:0.69:0.35 in 2006 and 1:0.68:0.45 in 2007.SourceofvarianceSSDegreeoffreedomdfMeansquaresMSFProbabilitylevel,PAge223.02572111.512982.84770.0001Site68.9879611.49808.54230.0098Year7.041717.04175.23160.0622Year×Age2.320621.16030.86200.4687Year×Site17.451335.81714.32180.0604Site×Age44.6304123.71922.76320.1107Error8.076061.3460Total335.229532Table 1 Analysis of variance of factors affecting the transmission rate of overwintering Laodelphax striatellus FallenSBPHoriginationsAgeofsmallbrownplanthopper(SBPH)20062007MacropterBrachypterLargenymphMacropterBrachypterLargenymphHaiyan3.36.258.233.525.026.12Haining3.855.136.992.143.035.81Jiashang2.783.836.222.594.216.25Tongxiang3.547.6913.64Xiuzhou3.595.267.13Changxin2.604.228.505.636.487.69Huzhou1.829.0911.29Mean±SE2.87±0.345.7±0.948.25±0.873.5±0.495.28±0.677.77±0.215%cbababa1%BAABABATable 2 Comparison of transmission rate (%) of the rice stripe virus by different age of the small brown planthopper (SBPH), Laodelphax striatellus FallenThe experiment presented in the paper showed that the large nymphs of the planthopper vector had higher transmission efficiency than their adults.Such discrepancy between adults and younger stages are found in many plant virus vectors.For both sexes of Frankliniella occidentalis(Pergande)(Thysanoptera:Thripidae),the vector of the tomato spotted wilt virus,the transmission efficiency dropped with age,simultaneously with the consumption rate(van de Wetering et al.1999).The transmission of Tomato spotted wilt virus by Thrips tabaci adults decreased with the age too at which the virus was acquired by larvae(Chatzivassiliou et al.,2002).In aphid vector of the persistent transmission of plant viruses,transmission efficiency decline with age though they remain infectivefor a long time,possibly over their whole life.Infectivity is not affected by molting,important because of existence of the virus as aphids mature.Foregut and hind gut is lined with cuticle that is shed with the molt;viruses transmitted in a persistent fashion must be either in midgut or within the body.But Ling(1975)noted that adult green leafhopper(Nephotettix virescens)is three times more efficient vector than nymphs in rice tungro transmission.The acquisition access period(AAP)and inoculation access feeding periods(IAP)are two of the important factors determining the transmission efficiency.The proportion of aster leafhoppers,Macrosteles quadrilineatus Forbes,that became vectors was significantly higher for bolt strain of aster yellows phytoplasma when leafhoppers acquired aster yellows phytoplasma as nymphs than as adults.Once leafhoppers became inoculative,the rate of transmission remained constant over their life spans(Murral et al.1996).Acquisition only occurs in the first and early second nymphal stages of the life-cycle and adult thrips cannot acquire the virus(Moritz et al.,2004).Due to the lack of strong evidence to elucidate the mechanism undergoing the different transmission ability between the ages and wing-morphs of the small brown planthopper,more experiments are necessary to carried out to draw the clear pictures.When winter crops such wheat,ryegrass are spatially connected with or temporally followed by rice seedling nursery or transplanted rice,viruliferous planthopper nymphs remained in the nearby winter crops or grasses will move by jumping to the newly-planted rice plants and transmit the virus to rice resulting in severer RSV incidence than viruliferous adults.Such event should be prevent through spatially and temporally isolation.Postpone of sowing date of rice has been tested experimentally as one of the effective approach to avoid RSV disease outbreak in rice(Zhu,et al.2007,in review).Additionally,the data can be used in a rice stripe disease epidemiological model to evaluate strategies for the disease management.The research presented in the paper is part of the Zhejiang Provincial Key Projects(2005C32033,2004E60055),China National High-Tech(863)Program(2007AA10Z220).

洋葱伯克氏菌（Burkholderia cepacia）是一种广泛存在于土壤、水和植物根围、与医院感染病人密切相关的革兰氏阴性细菌。它最初作为植物病原菌被认识，后来发现它也是医院中重要的人体条件致病菌，由该菌引起患者洋葱伯克氏菌综合症的致死事件在国内外均有报道。同时它在农业领域中具有生物防治、生物降解和促进植物生长等多种功能。近年来，该菌被认为不是一个种，而是一组基因型不同、表型相近的复合物，称为洋葱伯克氏菌群（Burkholderia cepacia complex，简称Bcc）。因此，重新认识医院和自然环境中的Bcc菌对于Bcc生防因子的风险评估尤为重要。Bcc菌致病基因的发现和挖掘将有助于更好的认识病菌的致病机制。目前已证实的毒力基因有BCESM和cblA基因。这些毒力基因大部分存在于医院菌，以在基因型Ⅲ菌株中分布率最高。虽然大量与囊性肺纤维化患者致病相关的Bcc致病菌及生防菌已被用来风险评估，但其他来源Bcc菌的毒力研究相对较少。近年来研究表明，苜蓿可以作为评估Bcc基因型毒力因子侵染的植物模型。因此，本试验采用苜蓿植物模型对来源于中国自然环境和医院中的Bcc菌株进行了毒力测定，同时也对两个毒力基因BCESM和cblA进行了特异性PCR检测，以便为评价所获Bcc不同基因型菌株的安全性提供重要依据。研究结果表明，来源于医院的基因型Ⅰ和Ⅲ菌株均对苜蓿幼苗有较强的毒力，幼苗子叶黄化或白化，根短小、畸形，对苜蓿幼苗的平均发病率分别达到69%和68%。来源于自然环境的Bcc菌株中，基因型ⅢB也对苜蓿幼苗表现出强毒力，幼苗症状类似于医院致病菌的致病效果，幼苗平均发病率为55%；基因型Ⅰ菌株对苜蓿幼苗的毒力程度较轻，有的菌株没有致幼苗发病；基因型Ⅴ和Ⅸ的多数菌株对苜蓿幼苗发病率很低，部分菌株不致幼苗发病。这说明来源于自然环境的基因型ⅢB菌株与医院致病菌的基因型ⅢA和Ⅰ菌株具有相同的毒力，表明自然环境中的基因型ⅢB菌可能为潜在的人体条件致病菌。同时研究表明，在这些Bcc菌株中，未检测到BCESM和cblA这两个毒力基因。

茄科青枯菌[Ralstonia solanacearum（E.F.Smith）Yabuuchi et al.]是世界上最重要植物病原细菌之一。该病原菌的寄主范围很广，可侵染44科数百种植物。该病原菌种内存在明显的异质性和多样性，根据其寄主范围或对碳水化合物利用差异，分别划分为5个生理小种和5个生化变种。广东地处亚热带，气候温暖湿润，终年适合作物生长，这为茄科青枯菌侵染引起的作物青枯病发生与流行创造了条件，每年均造成较大的经济损失。以前的研究结果表明，广东茄科青枯菌存在明显的致病性分化。为了深入研究该病原菌种内分化，对采自广东各种作物上的茄科青枯菌菌株进行了分子分析。从200条随机引物中筛选出17条扩增带清晰且扩增结果稳定的随机引物，用这些引物分别对31株茄科青枯病菌DNA进行RAPD分析。结果显示，17条随机引物扩增带主要分布于0.35～3.5kb范围，共扩增出523条带，其中468条为多态性带，占89.5%，说明广东茄科青枯菌DNA存在较丰富的遗传多态性。RAPD结果的聚类分析可以将上述31株茄科青枯菌划分为4个簇群，这些簇群与寄主植物间存在较高程度的相关性，说明青枯菌的致病性分化是由于其DNA上的差异所致。对分离自广东各地番茄、茄子、烟草、辣椒、空心菜、沙姜、姜、马铃薯、花生、菊花、桑树和藿香等12种作物21株茄科青枯菌菌株16S rDNA和16S～23S ITS克隆和序列分析表明，这些菌株16S rDNA序列间同源率大于99%，ITS序列间同源率大于93%，说明广东茄科青枯菌16S rDNA序列高度保守，而16S～23S rDNA ITS序列也很保守。

虫草属（Cordyceps）属于真菌门（Eumycota）、子囊菌亚门（Ascomycotina）、核菌纲（Pyrenomyceres）、麦角菌目（Clavicipitales）、麦角菌科（Clavicipitaceae）。本属真菌绝大多数能感染昆虫，并从其头部或体表长出子座体而构成虫、菌复合体——虫草。我国是世界上最早将虫生真菌——冬虫夏草进行药用的国家[1～6]，受我国对虫草传统药用的启发，加上微生物制药的诸多优点，近年来世界上许多国家都加强了虫生真菌的研究。初步研究已表明，虫草及相关真菌是最有潜力从中发现新型生物活性化合物或药物先导化合物的真菌类群[5～11]。根据寄生真菌和寄主的不同可以形成各式各样的虫草，虫草属作为药用真菌中的一个大类，目前报道虫草属真菌已达400多种，我国已记载的有90多种[12]。除冬虫夏草外，还有如霍克斯虫草、大团囊虫草、蛹虫草、珊瑚虫草、鳞翅目虫草等，其中冬虫夏草应用历史悠久，研究得最为深入[13]。尽管虫草在世界各地均有分布，但是相对集中地分布于亚欧大陆。研究表明，虫草可产生多种生理活性物质，这些物质分别具有抗菌、抗病毒、杀虫以及免疫调节等功能，它们在医药、农业、食品工业及现代生物技术的应用中皆有十分重要的意义。目前按其用途可将虫草资源分为3类：即药用、食用和害虫微生物防治资源。我国药用常用种有10余种，最多的是冬虫夏草（C.sinensis）群，其他还有蛹虫草（C.militaris）、亚香棒虫草（C.hawkesii）、大团囊虫草（C.ophioglossides）、凉山虫草（C.liangshanensis）、香棒虫草（C.barnesii）、古尼虫草（C.gunnii）、蝉花（C.sobolifera）等。对于虫草的认识，我国可追溯到公元前11世纪西周至秦朝。从出土的文物中就发现有以虫草作图案的玉雕饰品[14]。1578年成书的《本草纲目》中记载有雪蚕，根据其生活史、性味功效、形态、环境及产地判断，应当是冬虫夏草的古名。在1694年清朝汪昂的《本草备要》中也有关于冬虫夏草的论述，该书记载：“冬虫夏草，甘平，保肺益肾，止血化痰，止劳咳。四川嘉定府所产者佳。冬在土中形如老蚕，有毛能动，至夏则毛出土上，连身俱化成草”，这是冬虫夏草的最早文字记载[3]。赵学敏（1765）著的《本草纲目拾遗》把它的药用归之为“能治诸虚百损”[15～16]。在中华医药百味中，虫草正是以“治诸虚百损”、“阴阳平衡”、“保肺益肾、补精益气、专补命门”的神奇功效被认为是一种不可多得的中药之宝而蜚声华夏，饮誉海外，与人参、鹿茸齐名[14]，共称为中国的三大补品。虫草菌无性型种类包括20余属70余种，其中重要的有拟青霉属17种，头孢霉属6种，层梗孢属l1种，被毛孢属21种，葡萄穗霉属1种，小束梗孢属2种，刺束霉属3种，球束孢霉属1种，轮枝孢属3种，侧孢霉属3种及多头霉属的一些种，其中拟青霉、被毛孢霉、头孢霉及轮枝孢霉的许多种已用于害虫生物防治。早在20世纪50年代，前苏联科学家就用棒形虫草（Cordyceps clavulata）的性型蜡蚧被毛孢（Hirsutella lecanicola）人工培养后防治核桃介壳虫，并获得成功。Shimazu（1988）确证的布氏虫草（Cordyceps brongniartii）及其无性型布氏白僵菌（Beauveria brongniartii），是金龟子幼虫一种常见的病原，多年来日本、法国及我国利用该菌防治森林苗圃、牧场及农田的蛴螬均有较好的效果，在有些场合下可较长期地控制虫口。随着化学农药的大量使用对环境生态的严重影响，生物防治日益被人们所重视，利用昆虫病原微生物防治害虫是重要的手段之一。虫生真菌种类多，代谢类型复杂，以其安全有效，显著的流行潜力，容易大量生产等优点，在害虫的生物防治中占有越来越重要的地位。目前生物防治中应用最广的真菌杀虫剂是白僵菌、绿僵菌、汤普森多毛菌、蜡蚧轮枝菌、拟青霉等。据试验，白僵菌用于防治农、林、果、茶类30余种害虫，均取得良好的效果。国外对白僵菌研究较多的国家有前苏联、美国、日本、法国、德国等。前苏联在20世纪70年代批准登记为Boverin微生物杀虫剂，用作大面积防治马铃薯甲虫、苹果食心虫、小麦盾蝽、玉米螟和甜菜象甲等。我国利用该菌防治农林害虫每年达67万hm2 以上。绿僵菌仅次于白僵菌，目前美国、巴西已有绿僵菌商品制剂，主要用于防治沫蝉、蚊子等。国内应用其防治梨虎、天牛、梨心毛虫、菜青虫、蠹虫、蚊子等，其防效达30%～94%。有关资料显示，目前虫生真菌制剂的研究进展依然缓慢。至1996年，国外登记注册的只有27种剂型，40多种不同的虫生真菌制剂，其中主要为球孢白僵菌和金龟绿僵菌，而国内的商业产品均未形成[17]。因此，还有待于国内科研工作者进行广泛深入的研究。我国虫草资源主要用于药用，其次是食用，作为生物杀虫剂尚处在试验研究阶段。近年来由于人工滥采乱挖，以及生态环境的严重破坏，许多虫草菌面临灭绝的危险。研究人员已意识到这一点，从菌种分类、种类分布、生态、寄主、人工驯化与培养、化学成分、药理与临床等方面做了大量的研究，发现人工培养的菌丝体和发酵液，经化学、药理研究证明与天然虫草基本一致[18]，这无疑为虫草的获得开辟了一条新途径。总之，虫草属真菌的研究还有很多地方有待深入。虫草的药用价值和微生物防治还有很大的潜力可挖，只要广大真菌工作者不懈努力，这一古老的药用真菌必将为人类健康做出新的贡献。