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1.
报道了宁夏2个新分布记录属:斑叶兰属Goodyera R.Br.、单侧花属Orthilia Rafin.;4个新分布记录种:小斑叶兰Goodyera repens R.Br.、钝叶单侧花Orthilia obtusata Hara.、短梗涩芥Malcolmia karelinii Lipsky.、短瓣繁缕Stellaria brachypetala Bunge,以及22种罗山新记录种。  相似文献   

2.
文中报道了禾本科(Gramineae)植物在新疆的新分布记录1属1种,分别是新记录分布属:锋芒草属(Tragus Hall.),新记录分布种:锋芒草(Tragus racemosus(L.)All.)。  相似文献   

3.
羊蹄齿胫叶(虫甲)(Gasfrophysa alrocyfltlca Motschulsky) (又名蓼蓝角胫叶(虫甲))和凹胸萤叶(虫甲)(Inadimonia polanini Ogloblin),也是田园重要杂草巴天酸模(Rumex patientia L.)的天敌。现就田间观察和室内饲养的结果简报如下:  相似文献   

4.
苍耳属(Xanthium L.)植物具有较强的入侵性,对农林业生产有较大的影响.为有效防治和控制刺苍耳(X.spinosum)和意大利苍耳(X.italicum)在宁夏的入侵态势,对这2种植物在宁夏的入侵情况、分布状况、生长情况进行了调查研究.结果表明,刺苍耳在宁夏地区以同心县为中心,形成了严重的入侵危害,并开始向周边...  相似文献   

5.
中国伊犁河谷种子植物区系分析   总被引：5，自引：1，他引：4  
根据野外调查,采集植物标本以及对所收集的资料进行整理,构建中国伊犁河谷野生种子植物名录,在此基础上展开种子植物区系分析。研究表明:中国伊犁河谷共有野生种子植物1 655种,归属于486属83科;优势科为菊科(Compositae)、禾本科(G ram ineae)、豆科(Legum inosae)等18科,表征科为罂粟科(Papaveraceae)、藜科(Che-nopod iaceae)、蓼科(Polygonaceae)和石竹科(Caryophyllaceae)4科;优势属为苔草属(Carex)、拉拉藤属(Galium)、早熟禾属(Poa)等18属,表征属为披碱草属(Elymus)、鹤虱属(Lappula)、锦鸡儿属(Caragana)和蒲公英属(Taraxa-cum)4属;科和属的地理成分主要为温带成分,分别占53.66%和65.65%(不包括广布型),中国特有和东亚特有成分极少甚至缺失,存在一个中亚特有科——鸢尾蒜科(Ixioliriaceae)。  相似文献   

6.
自沙芥属(Pugionium Gaertn.)建立以来,本属先后发表了5种及1变种。但就个别种或变种的存在与否及其分布问题,学术界长期以来一直存在争议。作者经查阅标本及在几种植物的主要分布区进行实地调查,通过对本属植物根、叶的形态解剖学结构及种子特性等方面比较研究,认为:本属植物共4种,即沙芥(P. cornutum Gaertn.)、斧形沙芥(P. dolabratum Maxim.)、距沙芥(P. calcaratum Kom.)和翅果沙芥(P. pterocarpum Kom.)。作者同意齿冠沙芥(P. cristatum Kom.)应与斧形沙芥合并,至于宽翅沙芥(P. dolabratum var. platypterum H. L. Yang)实际上就是翅果沙芥(P. pterocarpum Kom.),应予归并。  相似文献   

7.
寄生杂草无根藤的特性,危害与防除   总被引：1，自引：0，他引：1  
樟科无根藤属,是一类分布广、危害严重的藤本寄生杂草。分布于热带、亚热带地区,此属约15种,我国只有无根藤(Cassytha filiformis L.)一种,又称过天藤、无根草、流离网、飞扬藤、黄鱼藤、罗网藤、雾水藤、蜈蚣藤、青丝藤、半天云、无头藤、无娘藤、无地生根等。在我国分布于云南、贵州、四川、广西、广东、海南、湖南、江西、福建、浙江、台湾等省区。无根藤常寄生在乔木、灌木及草本植物上,其危害农林业生产的严重性,尚未引  相似文献   

8.
猪殃殃(Galium aparineL.)又名麦珠珠、拉拉殃,是睢宁县麦田的恶性杂草,较难防除。近年来,猪殃殃在睢宁县稻茬麦田大面积发生,旱茬麦田呈逐年加重发生趋势。为此,于2004~2005年进行了36%奔腾WP等除草剂在麦田的应用效果试验。1材料与方法1.1试验设计试验设在睢宁县睢城镇岗头村,试验地前茬为大豆,沙壤土,有机质含量1.8%,肥力中等,pH值7.5。试验小麦品种为淮麦20,10月6日播种,浅旋耕撒播。试验设冬前用36%奔腾WP(美国FMC公司生产)60 g/hm2、70.5%哈利DF(美国FMC公司生产)450 g/hm2、40%快灭灵DF(美国FMC公司生产)45g/hm2、10%速效麦…  相似文献   

9.
为明确不同耕作模式下小麦田杂草发生规律及其危害,通过田间实地调查,初步探讨了耕翻秸秆还田、耕翻无秸秆还田、浅旋秸秆还田、浅旋无秸秆还田、免耕秸秆还田等5种耕作方式下小麦田杂草群落组成。结果表明,当前小麦田杂草发生种类有27种,分属于14科24属,其中,双子叶植物13科24种,单子叶植物1科3种。频度最高杂草主要有看麦娘(Alopecurus aequalis Sobol.)、硬草[Sclerochloa dura (L.) Beauv.]、早熟禾(Poa annua L.)、繁缕[Stellaria media (L.) Villars]、猪殃殃[Galium aparine L. var. tenerum (Gren. et Godr.)Rchb.]、荠菜[Capsella bursa-pastoris (L.) Medic]等,但不同耕作方式下杂草优势群落有所不同,5种耕作方式分别以硬草+看麦娘+繁缕+猪殃殃、猪殃殃+繁缕+硬草+荠菜、硬草+荠菜+繁缕+猪殃殃+看麦娘、猪殃殃+繁缕+硬草+荠菜+早熟禾、硬草+猪殃殃+看麦娘+荠菜+繁缕为优势杂草群落,其中硬草+猪殃殃+繁缕为群落基本结构。不同播种方式对杂草的发生没有影响,而水旱轮作、秸秆还田对杂草具有一定的控制作用。  相似文献   

10.
报道了河西走廊北山维管植物分布新记录种11个:石生孩儿参(Pseudostellaria rupestris(Turcz.)Pax)、矮生豆列当(Mannagettaea hummelii H.Smith)、西域龙胆(Gentiana clarkei Kusnezow)、颈果草(Metaeritrichium microuloides W.C.Wang)、青藏蒿(Artemisia duthreuil-de-rhinsi Krasch.)、重冠紫菀(Aster diplostephioides(DC.)C.B.Clarke.)、微药羊茅(Festuca nitidula Stapf)、太白细柄茅Ptilagrostis concinna(Hook.f.)Roshev.)、双叉细柄茅(Ptilagrostis dichotoma Keng)、疏花针茅(Stipa penicillata Hand.-Mazz.)和无味薹草Carex pseudofoetida Kükenth.)。祁连山维管植物分布新记录1种:密囊韭(Allium subtilissimum L.)。既是北山也是祁连山维管植物分布新记录1种:毓泉风毛菊(Saussurea mae H.C.Fu)。其中石生孩儿参(P.rupestris)、西域龙胆(G.clarkei)、青藏蒿A.duthreuil-de-rhinsi)、毓泉风毛菊(S.mae)、无味薹草(C.pseudofoetida)和密囊韭(A.subtilissimum)这6种植物也是甘肃省分布新记录种。相关凭证标本存放于内蒙古大学标本馆(HIMC)。  相似文献   

11.
Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.  相似文献   

12.
Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.  相似文献   

13.
The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.  相似文献   

14.
Plant Viruses Transmitted by Whiteflies   总被引：18，自引：0，他引：18  
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.  相似文献   

15.
Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.  相似文献   

16.
A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

17.
The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.  相似文献   

18.
Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However, where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas. Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within populations is important in the selection of resistant genotypes.  相似文献   

19.
In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.  相似文献   

20.
In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.  相似文献   

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