黄瓜花叶病毒分离物核酸酶保护试验(RPA)方法的株系分化研究

 采用黄瓜花叶病毒((CMV)亚组Ⅰ株系Fny-CMV及亚组Ⅱ株系Ls-CMV的RNA₂的特定序列片段的cDNA克隆,体外转录,同时掺入³²P标记制备负链RNA探针,再与纯化的甜椒上的CMV中国分离物的RNA进行杂交,检测其与探针之间的同源性。共检测样品分离物3份。试验结果表明:河南新乡和北京密云的CMV甜椒分离物与Fny-CMV的核苷酸有高度同源性,隶属于Fny-CMV为代表的亚组Ⅰ株系。来自福建的样品与亚组Ⅱ的Ls-CMV株系有高度同源性,隶属于CMV亚组Ⅱ株系。本试验同时利用源于我国CMV亚组Ⅰ的K株系的RNA₂两个EcoR Ⅰ位点间1657-2125 nt的核苷酸序列为探针,同样与以上3份CMV中国分离物进行RNA杂交,进一步比较分析了这几个分离物与我国亚组Ⅰ的K-CMV株系的关系,证明了我国CMV存在亚组与株系分化。     

凤仙花花叶病的病原鉴定

<正>0引言凤仙花(Impatiens balsamina)为凤仙花科(Balsaminaceae)凤仙花属(Impatiens)一年生草本植物,在我国大部分地区均有分布。栽培过程中凤仙花真菌病害主要有白粉病、褐斑病、炭疽病和立枯病等^[1-2]。有关凤仙花病毒病的报道,如番茄斑萎病毒(tomato spotted wilt virus,TSWV)^[3]、凤仙花坏死斑点病毒(impatiens necrotic spot virus,INSV)^[4]、黄瓜花叶病毒(cucumber mosaic virus,CMV)^[5-6]、烟草花叶病毒(tobacco mosaic virus,TMV)^[7]、番茄花叶病毒(tomato mosaic virus,ToMV)^[8]、长叶车前花叶病毒(ribgrass mosaic virus,RMV)^[9]等均可侵染凤仙花。     

蘋果花叶病試驗初报

 苹果花叶病的分布广泛。据国外报导,在苏联^[55]、保加利亚^[20]、法国^[16]、英国^[63]、荷兰^[16]、瑞士^[15]、比利时^[58]、瑞典^[36]、挪威^[56]、意大利^[30]、南斯拉夫^[61]、美国^[13]、南非联邦^[38]、新西兰^[10]、印度^[12]以及德国、丹麦、澳大利亚等处均有此病的分布。     

引起花生果腐病的新孢镰刀菌及其生物学特性

<正>0引言花生果腐病(俗称花生烂果病)是一种世界性土传病害,主要导致花生荚果腐烂。近年来花生果腐病在我国山东、河南、河北等花生主产区日趋严重,造成15%以上的减产甚至绝收^[1]。国内外已报道的花生果腐病病原菌有Sclerotium minor^[2]、Neocosmospora vasinfecta^[3,4]、N. striata^[5]、Fusarium sp.^[6]、Pythium myriotylum^[7]和Rhizoctonia solani^[8]。其中,我国不同地域的花生果腐病病原菌有N. vasinfecta^[3,4]、N. striata^[5]、Fusarium sp.^[6]、P. myriotylum^[7]和R. solani^[8]。     

山药潜隐病毒RT-LAMP快速检测方法的建立

<正>0引言山药(Dioscorea oppositifolia L．)是薯蓣科薯蓣属植物,可作为药用或食用材料^[1],广泛分布于全球热带及亚热带地区,在我国河南、山东、江苏、广西和江西等省份都有种植。山药生产中以块茎无性繁殖方式为主,导致病毒病发生严重^[2]。侵染山药的病毒主要包括马铃薯Y病毒属(Potyvirus)^[3]、杆状DNA病毒属(Badnavirus)^[4]、香石竹潜隐病毒属(Carlavirus)^[5]以及蚕豆病毒属(Fabavirus)^[6]的一些病毒。     

观赏百合感染黄瓜花叶病毒后的超微病变研究

 黄瓜花叶病毒(Cymbidium mosaic virus,CMV)是雀麦花叶病毒科(Bromoviridae)黄瓜花叶病毒属(Cucumovirus)的典型成员,寄主范围极其广泛,能侵染1000多种的单、双子叶植物.该病毒可经75种蚜虫传播,有些分离物还可通过种子传播,是寄主植物最多、分布最广、最具经济重要性的植物病毒之一^[1].     

椰枣叶斑病的病原鉴定

<正>椰枣树(Phoenix dactylifera L.)属多年生棕榈科热带植物，是阿拉伯国家重要的经济和粮食作物，果实被称为“沙漠面包”,具有较高的营养价值^[1-2]。 目前我国对椰枣的研究主要集中于椰枣化学成分分析^[3]、基因表达^[4]、植物组织培养^[5]、逆境胁迫^[6]等领域，对椰枣病害发生及病原菌种类鲜有报道。2020年11月—2021年6月，对海南省椰枣病害发生情况进行调查，     

广西地区的桑寄生科植物

 本科植物据资料记载^[1,2],共30属,850种,欧洲、亚洲、北美、南美、澳大利亚均有分布^[3],主要在热带与亚热带;产于我国的有6属、40余种。     

分离自我国北方玉米叶斑的链格孢和弯孢属真菌

<正>0引言国内由链格孢属(Alternaria)和弯孢属(Curvularia)真菌引起的玉米叶斑病在黑龙江、吉林、河南、海南等地都有报道^[1-8];在青海发生的玉米叶斑病多由Alternaria引起^[9];而在辽宁、内蒙古、北京、河北、山东、陕西和四川等地发生的玉米叶斑病多由Curvularia引起^[6,10-12]。根据多基因序列分析鉴定的种有A. burnsii[3];据rDNA ITS^[4,9]或多基因^[3]鉴定的种有A. alternata、A. tenuissima和Alternaria sp.;     

海南海芋叶斑病病原鉴定

<正>海芋(Alocasia odora)又名滴水观音，为天南星科海芋属多年生大型常绿观叶草本植物，主要分布于我国海南、福建、广西等热带和亚热带地区^[1-2],广泛用于城市园林造景工程，也可作为室内观赏植物^[3-4]。海芋常见的病害有叶斑病、枯萎病、基腐病等^[5], 其病原菌分别为海芋链格孢(Alternaria alocasiae)、尖孢镰刀菌(Fusarium oxysporum)、烟草疫霉(Phytophthora nicotianae)^[6-7]。     

Localization of metabolic sites of action of herbicides

Time- and concentration-course studies were conducted to determine the effect of thirteen herbicides on photosynthesis, respiration, RNA synthesis, protein synthesis, and lipid synthesis using isolated single leaf cells. Each herbicide was from a different chemical class. Appropriate ¹⁴C-substrates and product purification procedures were used for each process prior to liquid scintillation counting. The most sensitive metabolic site of inhibition was photosynthesis for atrazine, bromacil, dichlobenil, monuron, and paraquat; RNA synthesis for dalapon and dinoseb; protein synthesis for chlorpropham; and lipid synthesis for CDAA, chloramben, 2,4-D, EPTC, and trifluralin. However, with several herbicides, one or more process was almost as sensitive as the one mentioned above. All herbicides inhibited more than one process, and the most sensitive site of inhibition may not be the same process that was inhibited the greatest at the maximum concentration and maximum exposure time used. Therefore, a concept of metabolic sites of action, rather than a primary site of action, appears to be more meaningful for herbicides.     

福寿螺配偶个体大小选择性初步观察

通过野外观察与实验研究,掌握了福寿螺的婚配体制及其配偶选择性规律。福寿螺与多数低等动物一样,其婚配属于乱交制,无固定配偶;雌螺对与其交配的雄螺个体大小没有选择性,而雄螺对雌螺的个体大小有选择性,倾向于与较大个的雌螺交配。     

青稞种子带菌检测及杀菌剂消毒处理效果

为了研究青稞种子外部和内部携带真菌情况,比较不同杀菌剂对青稞种子的带菌消毒效果和对幼苗生长的影响,为青稞种子播前包衣处理和种传真菌病害防控提供依据,采用离体平皿法对云南迪庆‘云青1号’、‘云青2号’和‘短白青稞’3个主栽品种进行带菌检测,并对种子进行拌种或浸种处理测定6种杀菌剂对种子消毒效果,分析杀菌剂对种子发芽和幼苗生长的影响。结果表明:供试青稞种子表面携带的优势菌群为青霉(Penicilliumspp.)、镰刀菌(Fusariumspp.);种子内部寄藏的真菌主要为镰刀菌、核腔菌(Pyrenophoraspp.)、附球菌(Epicoccumspp.)、丝核菌(Rhizoctoniaspp.)、链格孢(Alternariaspp.)和木霉(Trichoderma spp.)。青稞不同品种的种子表面及内部携带的真菌种类差异较大。致病性测定表明,镰刀菌对种子萌发和幼苗生长影响最大,后期出现幼苗坏死现象。45%咪鲜胺EW、75%百菌清WP、50%福美双WP对青稞种子携带真菌均有显著抑制作用和消毒效果,50%福美双WP消毒效果最优,达100%;45%咪鲜胺EW、75%百菌清WP、50%福美双WP处理对青稞种子发芽和幼苗生长均无显著影响。     

Effects of timing and method of application of Penicillium oxalicum on efficacy and duration of control of Fusarium wilt of tomato

The effects of timing and method of application of Penicillium oxalicum on the control of fusarium wilt of tomato were investigated. Application of P. oxalicum to tomato seedlings in seedbeds reduced disease caused by Fusarium oxysporum f.sp. lycopersici in a growth chamber by 45–49% and in glasshouse experiments by 22–69%. Disease suppression was maintained for 60–100 days after inoculation with the pathogen in the glasshouse. No disease reduction was observed in tomato plants where P. oxalicum was applied to seeds. Treatment with P. oxalicum did not affect the population of F. oxysporum f.sp. lycopersici in the rhizosphere.     

厚朴病虫害种类的初步调查

采用标准地法和线路调查法,对湖北恩施市新塘乡双河厚朴基地的厚朴病虫害进行了系统调查,记录主要虫害13种,其中叶部害虫9种,枝干害虫2种,根部害虫2种。厚朴主要病害5种。藤壶蚧、厚朴枝角叶蜂和厚朴新丽斑蚜为湖北省首次报道,小绿叶蝉为厚朴新寄主记录种。同时记录了藤壶蚧的天敌6种,其中寄生小蜂2种,瓢虫4种;厚朴新丽斑蚜的天敌昆虫8种。对藤壶蚧、厚朴枝角叶蜂和厚朴苗木根腐病等重要病虫害的发生规律进行了初步调查,同时提出了防治建议。     

黑麦草属DNA条形码鉴定技术研究

以毒麦、田毒麦、多花黑麦草、多年生黑麦草、硬直黑麦草、高羊茅与狗牙根等禾本科的7种植物为材料,拟采用 DNA 测序、特异性位点比对、种间遗传距离测定、建立系统树等分析候选 DNA 条形码 psbA-trnH 鉴别黑麦草属常见植物的能力。实验结果表明,以 psbA-trnH 为 DNA 条形码时,建立的系统发育树能较好区分毒麦和田毒麦与其他几种植物。psbA-trnH 序列可以作为黑麦草属植物的潜在条形码。     

棉花黄萎病菌致病型的AFLP分析

 选用41个棉花黄萎病菌(Verticillium dahliae)代表菌系,在温室条件下,对4个棉花品种鄂荆1号(感)、中棉所12(耐)、文-5(抗)和唐棉2号(抗)进行致病性测定,结果可将供试菌系分为落叶型与非落叶型2类。选取8对AFLP引物PCR扩增的结果中,统计带型稳定、清晰且有多态性的条带,共169条作系统聚类分析,将上述菌系分为2大类,第一类为非落叶型菌系,包括10个非落叶型菌系和1个过渡菌系;第二类为30个落叶型菌系。根据聚类分析建立树状图,发现菌系与地理来源存在一定的相关性,而依据菌系致病力强弱分类则相关关系不大。选用25对EcoRⅠ和MseⅠ引物组合,对供试的41个V.dahliae进行AFLP扩增,筛选到2对引物E64(GACTGCGTACCAATTCGAC)、M53(GATGAGTCCTGAGTAACCG)和E49(GACTGCGTACCAATTCCAG)、M65(GAT-GAGTCCTGAGTAAGAG),能分别扩增出433bp和110bp2条仅为V.dahliae非落叶型菌系独有的特异片段,可将落叶型与非落叶型菌系分开,这2条特异片段被命名为EM₄₃₃和EM₁₁₀。     

Mode of action of etoxazole

The mode of action of the 2,4-diphenyl-1,3-oxazoline acaricide/insecticide etoxazole has been argued to be moulting inhibition, but experimental results supporting this hypothesis are lacking. This study investigated the effect of etoxazole on chitin biosynthesis in the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Etoxazole induced moulting defects in fall armyworm larvae similar, if not identical, to those caused by benzoylphenylureas, a well-known class of insecticidal chitin biosynthesis inhibitors. Furthermore, in contrast to untreated larvae, the chitin content in the integuments of larvae several days after treatment did not differ from that in freshly ecdysed individuals, thus suggesting strong chitin biosynthesis inhibition in vivo. A more detailed investigation of the inhibitory potential by incubating cultured integument pieces from larvae of S. frugiperda with [14C]N-acetyl-D-glucosamine, a radiolabelled chitin precursor, revealed I50 values of 2.95 and 0.071 microM for etoxazole and triflumuron respectively. The incorporation of radiolabel into potassium hydroxide-resistant material was inhibited by etoxazole in a dose-dependent manner. Based on these results, it is concluded that the acaricidal and insecticidal mode of action of etoxazole is chitin biosynthesis inhibition.     

Mode of action of meturine

The effect of meturine on the light processes of photosynthesis was studied.Meturine is a herbicide for weed control in potato and cotton crops. It is a N-phenyl—N-hydroxy—N′-methylurea.The experiments were carried out on isolated pea and spinach chloroplasts.When examining photosystem I, reduced DPIP was used as an electron donor, whereas methyl-viologen served as an electron acceptor. When examining photosystem II, DPIP represented the electron acceptor.The obtained experimental results have pointed to the absence of the effect of meturine upon the photoreaction I.Unlike N-phenyl—N′, N′-dimethylureas (CMU, DCMU) meturine has been a very weak inhibitor of photoreaction II.The authors explain the photoreaction II inhibition of chloroplasts from plants treated with herbicidal doses of meturine by conversion of N-phenyl—N-hydroxy—N′-methylurea into Hill reaction inhibitor(s). N-Phenyl—N′-methylurea can be one of such meturine metabolites.Meturine herbicidal action is accounted for by meturine transformation into Hill reaction inhibitor(s) in the plant tissues.