烟草抗CMV细胞突变系筛选系统的研究

在单倍体烟草6叶期接种CMV,接种前3d适当增施氮肥,接种后置28±2℃和自然光照条件下最适合CMV侵染和发病,发病后烟苗仅9或10位叶全部畸型褪绿,这是用绿岛法筛选抗CMV细胞突变系的临界选择压。用0.3％EMS(硫酸二乙酯)诱变烟苗心叶,接种CMV后置临界选择条件下从普通烟草良种Burley18的928个病株中选到每叶仅1～2个绿岛的畸型褪绿叶78片。截取绿岛进行组织培养得到146株无病试管苗,移栽盆钵后再接种CMV鉴定,选到抗CMV突变系R_2和R_8,其当代无性系在夏季网室条件下病情指数较亲本低40.1～45.3,并能通过有性过程传递。     

侵染番红花的芜菁花叶病毒

 从表现花叶症状的德国进口番红花上获得一线状病毒分离物SA,线状病毒粒子长度为700~800nm。其在人工接种的11科39种植物中能侵染6科14种植物,在克里芙兰烟上产生系统坏死,在小白菜、花椰菜等十字花科植物上产生系统花叶或为隐症,在昆诺藜等藜科植物上为局部侵染。在番红花病叶、球茎及克里芙兰烟病叶组织中观察到卷轴状和片层状聚集的风轮状内含体。免疫吸附和免疫修饰电镜观察结果显示,SA与芜菁花叶病毒((TuMV)具有紧密的血清学关系。根据这些特征将SA鉴定为TuMV的一个分离物。这是TuMV侵染番红花的首次报道。     

甘蓝枯萎病苗期抗性鉴定技术及抗源筛选

为建立快速、有效的甘蓝枯萎病苗期抗性鉴定技术,采用温室盆栽方法,分别对甘蓝枯萎病苗期鉴定的接种浓度、接种方法、接种生育期、接种菌龄及接种适宜温度进行系统筛选与比较,并应用筛选出的最佳方法对108份不同来源的甘蓝资源进行抗枯萎病鉴定与评价。结果表明,甘蓝枯萎病苗期抗性鉴定最适接种浓度为106孢子/mL,接种生育期为2～3叶期,接种方法以将根部土抖落干净后直接浸根为最佳,最适宜发病温度为25～30℃,浸根时间及枯萎病菌菌龄对枯萎病鉴定结果影响不大;从108份不同来源甘蓝资源中筛选出40余份抗枯萎病材料,准确地反映了甘蓝资源对枯萎病的抗性程度。     

侵染蚕豆的芜菁花叶病毒的鉴定与提纯

 在江苏浙江等地的蚕豆苗上出现的红褐色环斑或白色斑驳症状.经鉴定是芜菁花叶病毒侵害的结果.在病组织中的病毒粒体为弯杆状.长度750-800nm。摩擦接种在苋色藜上,接种叶上出现大块黄色枯斑,直径约3毫米,顶叶系统感染,在克氏烟、芜菁、油菜上为系统花叶.在蚕豆苗上的症状,视品种和环境条件而异,在有限生长的品种上多为红褐色环斑.在启东蚕豆上多为白色斑驳,豆荚上也可出现变色斑。对病毒的提纯方法作了改进,用冻融的20%蔗糖溶液可代替常规的10-40%蔗糖梯度液,精提纯的效果相同。     

烟草花叶病毒六个分离物生物学性状初步研究

 测定了番茄条斑分离物(TMV-L₁)、番茄花叶分离物(TMV-L₂)、小青菜花叶分离物(TMV-B₁)、大白菜灰心病分离物(TMV-B₂)、地黄病毒病分离物(TMV-R)和烟草花叶分离物(TMV-N)在22科82种植物上的反应。六个分离物在心叶烟、曼陀萝等7种植物的接种叶上出现局部枯斑、在番茄,龙葵等9种植物上出现系统花叶,在White Barley烟,青箱等10种植物上反应的症状不同,在测试的十字花科植物、菊科等22种植物上六个分离物的侵染力不一致,部分分离物能够侵染,部分分离物不能侵染。对百合科、大麻科等11个科中的测试植物都没有侵染力。六分分离物中只有TMV-B₁和TMV-B₂寄主范围基本一致,仅症状轻重不同。     

结球甘蓝对TuMV和黑腐病的抗性鉴定

甘蓝对TuMV和黑腐病的抗性鉴定可采取分株分别接种和同株不同部位分别接种两种方法,鉴定结果基本一致。筛选出8020-2、8364等5份对TuMV免疫的抗原材料和23202-1、20-2-5-2等5份对TuMV、黑腐病具有复合抗性的材料。     

侵染唐菖蒲的烟草环斑病毒鉴定简报

1987年3月大连动植物检疫所送我所病毒室检验的唐菖蒲 Saxany 品种上,选取症状表现为斑驳的1病株,进行了鉴定,现简报如下。1.寄主范围及鉴别寄主反应:该病毒的寄主范围较广,汁液接种侵染6科10多种植物。在菜豆“Pinto”、家雀蛋、“Moroe”,豇豆“黑种三尺”、“黑眼”上,接种叶表现局部坏死环斑,系统生长点坏死;大豆“猴子毛”、“晋豆84”接种叶表现局部坏死斑,系统顶枯,昆诺阿藜、苋色藜、千日红、矮牵牛、克利夫兰烟接种叶表现为局部坏死斑;普通烟接     

不同病毒接种烟株对烟蚜生长发育和繁殖的影响

在室内25±0．5℃、RH 75%±5%、L:D=14:10条件下,研究了单独和混合接种黄瓜花叶病毒(CMV)、烟草花叶病毒(TMV)的烟株对烟蚜生长发育和繁殖的影响。结果表明,烟蚜取食健康烟株CK、CMV病株、TMV病株及CMV TMV病株叶碟后,若虫历期分别为6．04、6．26、6．79和8．04天,存活率分别为75．71%、55．84%、70．59%和32．00%,雌成蚜理论最大累积产仔数分别为22．44、6．35、4．99和5．49头,而种群内禀增长率r_m则分别为0．23、0．17、0．15和0．11。与健康烟株相比,接种各类型病毒的烟株对烟蚜种群有明显抑制作用,其中抑制作用最大的是CMV TMV混合接种的烟株。     

大豆花叶病毒的株系鉴定

作者用江苏省大豆重花叶(S_A)、轻花叶(S_B)、黄斑坏死(S_C)、顶枯(S_E)以及黑龙江的黄斑花叶(S_D)和顶枯(S_F)的分离物,在菜豆品种“Top Crop”的离体叶鉴定都产生局部枯斑。6个分离物都可以由几种蚜虫(桃蚜、萝卜蚜、苜蓿蚜)传毒,温度钝化点在50～55℃或55～60℃之间,稀释限点为10~(-2)或10~(-3),体外存活期(室温在25℃以上)为24～36小时,电镜下粒体形态都是线条形,它们的寄主范围都很窄,只侵染豆科植物中的少数几个种。这6个分离物都属于大豆花叶病毒。但是它们的寄主范围和在大豆品种上的反应有所不同、S_A和S_B对扁豆的侵染力很强,S_D和S_F不侵染扁豆,S_C和S_E侵染力居中,S_A和S_B在菜豆品种家雀蛋上发生系统花叶,其余四个分离物只在接种叶上出现黄斑和叶脉坏死。温室内测定了37个大豆品种或品系对6个分离物的反应,没有对6个分离物都免疫的品种,6个分离物在1138—2、493—1等9个品种都出现系统花叶,在合丰23、南农133—3、齐黄1号、徐豆1号和科系8号上,6个分离物的反应有稳定的明显的差异。根据6个分离物在大豆品种、扁豆和菜豆(家雀蛋)上的症状反应,认为6个分离物是大豆花叶病毒的6个不同株系,S_A和S_B的性状相似。室内测定同一个株系在不同品种上反应的症状不同,例如南京重型花叶S_A,轻花叶S_B在许多品种上出现系统花叶但在齐黄1号和徐豆1号上形成系统枯斑。黑龙江的顶枯S_F只在合丰23等少数品种上出现顶枯症状,多数品种是系统花叶。因此,症状类型不能代表株系的特征、而是株系与品种组合之间的特异性反应。我们认为用症状的表现来作为株系的名称是不一定确切的。     

西瓜蔓枯病菌子实体的诱导及抗性鉴定

在26～28℃,12h光照/12h黑暗的条件下,西瓜蔓枯病菌Didymella bryoniae在西瓜叶汁B培养基上培养3周左右,能形成大量黄褐色的小点即分生孢子器;而在21～23℃,12h光照(40W荧光灯)/12h黑暗的条件下培养,在西瓜叶汁C培养基能大量形成黑色小点即子囊座。来源不同的蔓枯病菌对西瓜的致病力差异显著。用致病力最强的蔓枯病病菌菌株XD-99-04-29-01 2～4×10~5孢子/ml孢子液,喷雾接种3～4叶期的西瓜苗,保湿120h,20个被鉴定的国内外西瓜组合/品种的蔓枯病病情指数在15～50,差异明显。对美国的4个品种的抗病性鉴定结果与先前的报道一致。     

High temperatures activate local viral multiplication and cell-to-cell movement of Melon necrotic spot virus but restrict expression of systemic symptoms

The infection of melon plants by Melon necrotic spot virus (MNSV) and the development of necrotic disease symptoms are a seasonal occurrence in Japan, which take place between winter and early summer, but not during mid-summer. In this paper we investigate the effect of three different temperatures (15, 20, and 25 degrees C) on the local and systemic expression of MNSV in melon plants. Previously, the incidence of plants expressing systemic symptoms caused by MNSV and other viruses was found to be greater at temperatures less than 20 degrees C. In this study, our temperature-shift experiments support previous studies that found the expression of systemic symptoms increases as temperature falls from 25 to 20 degrees C and decreases as temperature rises from 20 to 25 degrees C. However, MNSV replication in melon cells and local viral movement within leaves following the inoculation of melon protoplasts or cotyledons were more frequent at 25 degrees C than at 15 or 20 degrees C.     

水稻叶鞘腐败病的研究——Ⅰ.病原菌的致病性及发病的影响因子

 本文阐述了水稻叶鞘腐败病病原菌Sarocladium oryzae,在水稻各生育期和植株不同部位的叶鞘上之致病性以及由此产生的各种症状。该病原菌不仅在水稻各生育期发生危害,还能侵害叶鞘、谷粒、叶片中脉等。水稻剑叶叶鞘受害,常呈现为典型叶鞘腐败病病斑以及"紫鞘"或"紫鞘黄叶"症状。病谷常引起秧苗发病。发病的最适温度为30℃、湿度为70%(RH)。但发病对温湿度要求并不甚严格。适当的氮、磷、钾配比和适量施用能提高植株的抗病性,氮肥过多或缺乏均会加剧病害的发生与危害。品种的抗病性有着明显差异,但与水稻类型无关。以病原菌分生孢子液对21个常见杂草和野生稻接种,其中属于禾本科的15个种可引起发病。经田间调查,该病原菌也在自然条件下侵染若干禾本科杂草。     

Effects of inoculation of barley inflorescences with Drechslera teres upon the location of seed-borne inoculum and its transmission to seedlings as modified by temperature and soil moisture

An investigation of the location of Drechslera teres on barley (cv. Thibaut) seeds showed that, when artificial contamination was carried out at the time of flowering, all parts of the caryopsis. including the embryo, were infected by the two forms (f. teres and f. maculata ) of the pathogen. An assessment was made of the possible role of abiotic factors, including the effects of temperature and soil moisture, on the expression of the primary symptoms caused by the two forms of the pathogen. The most severe damage was observed in dry soils (pF 3-4) at temperatures off. 12°C. On young barley seedlings, the seed-borne inoculum caused coleoptile symptoms in the case of the form maculata , whereas the form teres induced mostly foliar symptoms. Foliar necroses may result from systemic invasion by the pathogen located in the seed.     

引起辣椒花叶、枯顶的一个病毒分离物的鉴定

 从河北望都辣椒地分离到一株辣椒病毒分离物.测定表明能侵染茄科、苋科、豆科、菊科、藜科的25种植物,不能侵染葫芦科和十字花科等13种植物.桃蚜（Myzus persicae）非持久性传毒;钝化温度65—70℃,稀释限点10^-4—10^-5体外保毒期6天（20—22℃）;病毒颗粒呈球形,直径约25nm;ISEM测定它与蚕豆萎蔫病毒（BBWV）关系密切;电镜下观察到BBWV所特有的长管状内含体和布纹状结晶体,认为该分离物是BBWV.但寄主范围和寄主反应与文献报道的BBWV各分离物有所不同,可能是另一毒株。     

向日葵霜霉病研究

 向日葵霜霉病菌Plasmopara halstedii (Farl.) Berl.&de Toni在5-25℃条件下均可侵染寄主,以10-15℃为侵染适温。对不向苗龄幼苗进行人工接种,3-14天的幼苗均被侵染,3天幼苗为最感病,发病率随植株苗龄增大而递减。病菌侵入寄主后,在恒温15℃、20℃、25℃ 4组及变温8℃和15℃、13℃和20℃、18℃和25℃、23℃和30℃条件下均可发病,恒温20℃及变温13℃和20℃发病率最高,恒温30℃及变温28℃和35℃不发病。     

中国水仙上一种球形病毒的研究Ⅰ.病毒分离及其生物学特性

 从水仙黄条病株上分离到一种球形病毒,直径约21nm,汁液摩擦接种35科(属)55(品)种植物,可侵染其中5科15(品)种,主要局限于豆种(Leguminosae)、藜科(Chenopodiaceae)以及茄科(Solanaceae)、苋科(Amaranthaceae)与番杏科(Aizoaceae)的个别种。在多数寄主上诱导局部坏死,豆科寄主上还伴随叶脉坏死症状产生。其中,昆诺阿藜(Chenopodium quinoa)、苋色藜(C.amaranticolor)、千日红(Gompherena globosa)、番杏(Tetragonia expansa)、大豆(Glycine max)、豇豆(Vigna sinensis)、克利夫兰烟(Nicotiana clevelandii)可作为诊断寄主;千日红、番杏与三叶草(Trifolium sibth)可作为毒源保存寄主。#br#在昆诺阿藜叶片汁液中,该病毒分离物的体外存活期在60天以上(25℃),热钝化点80-85℃(10分钟),稀释限点10^-5-10^-6。回接水仙健株,诱导产生系统褪绿条纹症状,不诱导水仙叶片产生具有特殊结构的内含体。     

长时间低温处理有助于加强黄瓜花叶病毒CMV-BF 2b基因的多态性

将被黄瓜花叶病毒CMV-BF株系侵染的三生烟(Nicotiana tabacum var.Samsun NN)的不同单株分成两组分别置于高温(30±5℃)和低温(10±5℃)条件下,观察和分析CMV-BF侵染30、80 d时植株的症状表现及CMV2b基因的序列变异规律。结果表明:侵染30d时,在高温环境中的植株表现出畸形叶片较多、病毒症状较严重的现象,而低温培养的植株细弱,部分叶片大面积白化;2b基因DNA序列的多态性也以高温处理组略高于低温组,但差异未达到显著水平。侵染80 d时,高温组植株的病毒症状有所恢复,畸形叶片减少,而低温组植株除白化现象更严重外,畸形叶片增多;2b基因的多态性以低温处理组明显高于高温组,且达到显著水平(P0.05)。因此,长时间低温处理有助于加强CMV-BF2b基因的多态性,而且2b基因的多态性可能与植株的病毒症状表现相关。     

温度对葡萄十星瓢萤叶甲交配行为的影响

在室内恒定条件下,测定了3种不同温度对葡萄十星瓢萤叶甲Oides decempunctata Billberg成虫的交配节律、交配次数和交配持续时间的影响,结果表明:(1)葡萄十星瓢萤叶甲成虫在白天各时间段均有发生,但只有25℃下才出现有交配的高峰(14:00和18:00),过低或过高的温度均无明显的高峰期出现.(2)每日平均交配次数随着温度的升高呈上升趋势,然而,每日耗费在交配中的总时长在25℃时达到最大(227.74 min),过低或过高的温度均使其受到抑制.(3)交配持续时间在22℃下最长(146.84 min),在28℃下最短(42.83 min),表现出随着温度的升高呈缩短的趋势.     

Effects of Temperature on Infection in Capsicum sp. and Nicotiana benthamiana by Impatiens Necrotic Spot Tospovirus

Infection by two isolates of impatiens necrotic spot tospovirus (INSV) under temperature regimes of 25/18°C (day/night) or 33°C (continuous) was studied in Capsicum annuum (systemically susceptible to tomato spotted wilt tospovirus, TSWV), C. chinense PI 152225 and PI 159236 (reacting hypersensitively to TSWV) and Nicotiana benthamiana (systemically susceptible to both tospoviruses). At 25/18°C infection was systemic in all hosts tested. At 33°C infection in N. benthamiana was systemic whereas in C. annuum and C. chinense it was restricted to the inoculated leaves. The result differed from that reported for TSWV, where high temperature made plants more susceptible, or caused no difference. Exchanging temperature regimes 6h to 4 days after inoculation did not affect the final results one month later, with plants being only locally infected at 33°C continuous regime, or systemically infected at 25/18°C alternate regime. The two INSV isolates were biologically and serologically stable for 5 passages in N. benthamiana held continuously at 33°C.     

Symptom development,in planta distribution,and transmission of <Emphasis Type="Italic">Impatiens necrotic spot virus</Emphasis> in gentian: evidence for survival in roots and winter buds

Impatiens necrotic spot virus (INSV) causes serious damage to gentian (Gentiana spp.). Symptom development, in planta distribution, and transmission of INSV were studied after mechanical inoculation of gentian plants and propagation of shoot cuttings from infected stock plants. When young gentian plants at the 2nd-leaf stage were inoculated with INSV, plants developed systemic symptoms that were restricted to a few upper leaves. However, older plants at the 6th-leaf stage did not develop systemic symptoms. After plant inoculation, INSV was detected using DAS-ELISA in symptomatic upper leaves, and rootlets and winter buds, but not in asymptomatic leaves. When asymptomatic shoot cuttings from infected stock plants were vegetatively propagated in a thrips-free glasshouse, 44.4% of those obtained from the apical shoot and 20.6% of those obtained from the middle section of the plant developed systemic symptoms. These results indicated that when gentian plants were infected with INSV, the virus was preferentially transported from the infected leaves to the root and winter buds. However, even asymptomatic shoot cuttings may develop systemic symptoms when obtained from infected stock plants. Therefore, vegetative propagation from infected stock plants can be a source of INSV infection.