厦门口岸全国首次截获郁金香X病毒

<正>2015年12月8日,厦门机场出入境检验检疫局入境的一批荷兰鲜切郁金香花,经厦门出入境检验检疫局技术中心植物检疫实验室检疫鉴定,携带郁金香X病毒(Tulip virus X,TVX)。这是我国口岸首次截获该病毒。郁金香X病毒最早发现于苏格兰的郁金香中,可引起郁金香叶片的褪绿和坏死,还可侵染烟草和香蜂花。该病毒可通过机械和螨类传播,以及种球等繁殖材料远距离传播。目前,除英国外,该病毒在荷     

大连海关全国首次从荷兰进境的百合种球中截获郁金香X病毒

正2020年7月,大窑湾海关入境的一批荷兰百合种球(西伯利亚),经大连海关技术中心检疫鉴定,携带郁金香X病毒(tulip virus X, TVX)。这是我国口岸首次在荷兰进境的百合种球中截获该病毒。郁金香X病毒是马铃薯X病毒属(Potexvirus)成员,最早在苏格兰的郁金香中分离出来,可通过鲜切花采收机械接触及种球携带远距离传播,在郁金香植株上引发叶片褪绿和坏死斑点、花被片中形成颜色     

进境郁金香种球腐烂病的病原鉴定

在来自荷兰的郁金香种球上发现一种能够在种球储藏期发生、为害的真菌病害.对发病种球进行病原菌分离纯化及形态学和分子生物学鉴定,经过科赫氏法则验证,确定引起该病害的病原菌为尖孢镰刀菌郁金香专化型(Fusarium oxysporum f.sp.tulipae).     

郁金香常见病虫害及其防治

郁金香属百合科 ,是世界著名的鳞茎类花卉之一。其绚丽多姿的花形和花色为广大游人所青睐。近几年 ,上海植物园成功地举办了数次郁金香花节 ,为广大市民提供了一个能欣赏这一名贵品种的场所。由于上海特殊的地理、气候环境 ,郁金香常会出现叶枯花小、盲花等不尽人意的现象。本文列举了上海地区几种常见的病虫害 ,并结合多年的栽培经验 ,从病虫害防治角度提出一套栽培管理和药剂防治相结合的防治措施。1　常见病虫种类(1)郁金香疫病 (Ｂｏｔｒｙｔｉｓｔｕｌｉｐａｅ)　属半知菌丛梗孢目葡萄孢属 ,主要危害叶片、花、球茎。叶片和花受害后 ,…     

百合脱毒组培技术研究

百合为百合科百合属(Lilium)多年生球根植物,是国际上主要鲜切花之一。百合在生产中一般采用无性繁殖,而百合病毒可通过种球传播。因此,病毒一旦感染百合,即在种球内不断积累,最终导致种质严重退化,给百合种植业造成巨大的经济损失。迄今已发现引起百合种球退化的病毒及其类似病原多达12种,其中危害最严重的有百合潜隐病毒(Lily symptomless virus,LSV),郁金香碎色病毒(Tulip breaking virus,TBV)和黄瓜花叶病毒(Cucumber mosaic virus,CMV)。随着组织培养技术的日臻成熟,通过组培脱毒为解决百合种球病毒性退化问题提供有效途径。国内外对百合组培脱毒进行的系列研究表明,获得脱毒苗的方     

郁金香和百合主要病害、病原及鉴定方法

郁金香和百合是最重要的百合科球根花卉。病害是制约郁金香和百合产业健康发展的重要因素。本文介绍了国内为害郁金香和百合的主要病害和病原。国内为害郁金香和百合的主要病原真菌有镰刀菌、灰霉和炭疽菌;主要病原细菌有萎蔫短小杆菌、果胶杆菌属和迪基氏属软腐细菌;主要病毒有郁金香碎色病毒、百合斑驳病毒、百合无症病毒和黄瓜花叶病毒等RNA病毒。主要植物病原线虫有短体线虫、茎线虫和滑刃线虫。线虫取食伤害郁金香和百合的根、鳞茎和芽,促进病原真菌和细菌对植物的复合侵染;毛刺属和拟毛刺属线虫除侵害郁金香和百合,还作为介体向植物传播烟草脆裂病毒。为害郁金香和百合的线虫,南芥菜花叶病毒、草莓潜隐环斑病毒和番茄环斑病毒等RNA病毒是与郁金香和百合相关的主要进境检疫性有害生物。本文也介绍了鉴定这些病原的常规方法和新方法,为建立郁金香和百合主要病原的检测检疫体系提供技术理论支持。     

进口郁金香种头应注意的问题

进口郁金香种头应注意的问题陈其文谭群英谢为龙（拱北动植物检疫局５１９０２０）郁金香是人们喜爱的名花，也是荷兰主要的出口花卉品种，荷兰的郁金香种头几乎出口到全世界。自８０年代末起，我国个别地区引进荷兰郁金香种头。最近，荷兰方面为了扩大郁金香市场，与我国...     

郁金香上的茎线虫

虽然茎线虫(Ditylenchus dipsaci)在水仙花上已经知道有许多年了,但直到1943年才在英国发现它侵染郁金香。在战后十年,郁金香茎线虫迅速扩展到荷兰重要的球茎种植区和英国林肯郡,并且成为郁金香行业较严重的问题之一。在防治上现已获得许多进展,但它仍然是需要严密注意的隐患。虽然在郁金香上的茎线虫是一个单独的小种,但     

绵羊肺腺瘤病

绵羊肺腺瘤病是绵羊的一种传染性肺脏肿瘤病,由反转录病毒引起。该病毒能与Mason-Pfizer猴病毒及小白鼠乳房病毒的抗血清起交叉反应,很难在体外组织培养基上生长,供研究的病毒来源只能局限于动物接种来延续。目前,许多国家的兽医研究人员发现在感染羊的外周循环血液中检测不到相应的抗体,同时对病毒基因组分析表明,在正常绵羊及山羊的细胞DNA中存在病毒基因组序列,说明羊肺腺瘤病是一种内源性及外源性病毒病。     

加纳的可可肿枝病

可可肿枝病毒在西非分布甚广,具有较重要的经济价值。其多数病毒株系引起明显的症状,降低产量,但不死树,除非有其他生物作二次侵染。然而也有一些致病力强分布甚广的株系,具有致死性。病害症状,茎和主根明显的肿胀、侧根坏死、落叶、结小国形杂色的豆荚,内含的豆粒比通常的少     

Pollination of chasmogamous flowers and the effects of light and emergence time on chasmogamy and cleistogamy in Monochoria vaginalis

Monochoria vaginalis is one of the most serious weeds of rice fields in Asia. The species has both chasmogamous (CH) and cleistogamous (CL) flowers on individual plants. The objective of this study is to clarify the reproductive characteristics that affect the selfing rate of M. vaginalis. An emasculation experiment revealed that the CH flowers emasculated just after flower opening produced seeds. The seed production in the flowers emasculated just after flower opening was less than that of the flowers emasculated and hand‐pollinated with pollen from another plant. These results indicate that, although self‐pollination before anthesis occurs, cross‐pollination also can produce seeds. An experimental manipulation of light and the emergence time of the plants revealed that more than half of the flowers produced were CL flowers and the CH/CL ratio decreased with reduced light availability. The plants that emerged later produced as many CH flowers as those that emerged earlier. There was no significant difference between the CH and CL flowers in the seed number per fruit and the seed mass. These results suggest that M. vaginalis has reproductive characteristics that make the selfing rate high; however, outcrossing also can occur. Under favorable light intensity conditions, such as on the edges of paddy fields or in fallow fields, M. vaginalis will produce more CH flowers and will have a higher outcrossing rate than in shaded conditions.     

Temporal Dynamics of the Biocontrol Agent Pseudomonas fluorescens Strain A506 in Flowers in Inoculated Pear Trees

ABSTRACT The colonization of individual flowers in mature pear orchards by Pseudomonas fluorescens strain A506 applied at different times during bloom was measured to determine the receptivity of flowers to colonization and the extent of intra-tree movement over time. Strain A506 populations in flowers open at inoculation were initially about 10(4) cells per flower and increased to approximately 10(6) cells per flower in flowers that were inoculated within about 5 days of opening. However, eventual populations decreased with further increases in flower age at inoculation to as few as about 10(3) cells per flower when inoculated flowers were more than 10 days old. Populations of strain A506 on flowers that opened after inoculation was initially very low at the time of petal expansion (<100 cells per flower) but increased rapidly with time after flower opening. The maximum population of strain A506 that developed on such flowers decreased with increasing time between inoculation and petal expansion; 10(4) to 10(5) cells of strain A506 eventually colonized flowers that opened within 7 days of inoculation, whereas fewer than 100 cells colonized flowers that opened 24 days or more after inoculation. Large total bacterial populations on A506-treated trees were associated with significant reductions in populations of Erwinia amylovora and reduced incidence of fire blight and severity of fruit russet.     

Potential and limits of acylcyclohexanediones for the control of blossom blight in apple and pear caused by Erwinia amylovora

Growth-regulating acylcyclohexanediones such as prohexadione-calcium and trinexapac-ethyl have been shown to be effective in controlling fire blight infections on shoots. Since blossoms represent the primary site of infection for the fire blight pathogen, Erwinia amylovora , trinexapac-ethyl and prohexadione-calcium were evaluated for their ability to reduce fire blight infection on apple and pear flowers. Field experiments and experiments under controlled conditions were conducted on apple flowers for 4 years. A reduction of up to 50% of blossom blight was observed in treated plants. In addition, treatment with trinexapac-ethyl reduced up to the 77% the percentage of fireblight-affected flowers from which disease progressed into shoots. On pear, numbers of flower infections were reduced by a quarter and flower infections leading to diseased shoots was reduced by up to 50%. Mechanisms underlying diseased reduction following treatment with the two acylcyclohexanediones was studied using a confocal laser scanning microscope combined with a gpf -labelled strain of E. amylovora . These non-invasive techniques demonstrated bacterial migration was reduced by up to 60 and 66% in apple and pear xylem, respectively.     

Description of symptoms and assessment of loss caused by some viruses in the carnation cultivar ‘william sim’

A study was made of the influence of carnation mottle, ring spot and vein mottle viruses on carnations of the ‘William Sim’ variety by artificial infection of virus-free plants of one single clone. No clear leaf symptoms were obtained by artificial infection with the mottle virus, but leaf symptoms appeared on plants infected with the ring spot virus and the growth of these plants was markedly reduced. The carnation vein mottle virus caused a definite leaf flecking. A depressing effect on yield was demonstrated with all three viruses. Vein mottle was serious, particularly because it caused flower colour breaking. The ring spot virus, also, had a depressing effect on the quality of the flowers, causing a high percentage of split calices. The carnation mottle virus also caused a reduction in the quality of the produce, though not so intense as that caused by the ring spot virus. A combination of the two last-mentioned viruses proved slightly more serious than the ring spot virus alone.     

Lily symptomless virus in tulip

Lily symptomless virus (LSV) was transmitted mechanically to only two out of 53 plant species (18 families) tested, i.e.Lilium formosanum and tulip ‘Rose Copland’ (Liliaceae). The aphid speciesMacrosiphum euphorbiae, Myzus persicae, andAphis gossypii transmitted LSV in a non-persistent manner fromLilium Mid-century hybrid ‘Enchantment’ to tulip ‘Rose Copland’.M. euphorbiae transmitted the virus more efficiently thanM. persicae andA. gossypii. The yield of LSV-infected tulips ‘Peerless Pink’ was slightly reduced compared with that of healthy tulips. LSV was observed incidentally in naturally infected commercial stocks. Two procedures to purify LSV from tulips were applied, one using crude sap and the other sap treated with chloroform. The length distribution of LSV particles in tulip showed a higher percentage of particles shorter than 600 nm as in lily.     

Some factors influencing the infection of tulip sprouts by Botrytis tulipae

It is generally assumed that tulip bulbs with symptoms of infection byBotrytis tulipae will produce diseased sprouts, but experiments have shown this danger to be relatively small. Sprout infection is found to be influenced by several factors, e.g. the degree of infection of the bulb, the presence of the brown tunic around diseased bulbs, the length of the growth period between planting and flowering, and the soil temperature. The yield of salable flowers was found to depend on the location and intensity of sprout infection; no flowers are formed when sprouts are heavily infected.     

<Emphasis Type="Italic">Odontoglossum ringspot virus</Emphasis> causing flower crinkle in <Emphasis Type="Italic">Phalaenopsis</Emphasis> hybrids

A new disorder exhibiting flower crinkle on Phalaenopsis orchids bearing white flowers has been observed in Taiwan, China and Japan for several years. This disorder decreased the flower longevity and was considered as a physiological syndrome. The objective of this study was to identify and characterize the real causal agent of this new Phalaenopsis disorder. Five plants of Phalaenopsis hybrids “V3” (Phal. Yukimai × Phal. Taisuco Kochdian) with flower crinkle symptoms were collected and tested by enzyme-linked immunosorbent assay with antisera against 18 viruses. The extract of leaves and flowers from one diseased plant (96-Ph-16) reacted positively only to antiserum against Odontoglossum ringspot virus (ORSV), while those from the other four plants (96-Ph-7, 96-Ph-17, 96-Ph-18 and 96-Ph-19) reacted positively to the antisera against ORSV and Cymbidium mosaic virus (CymMV). Five ORSV isolates, one each from flowers of those five diseased Phalaenopsis orchids, were established in Chenopodium quinoa. A CymMV culture was isolated from the flowers of one of the ORSV/CymMV mix-infected Phalaenopsis orchids (96-Ph-19). To determine the causal agent of the flower crinkle disease, healthy Phalaenopsis seedlings were singly or doubly inoculated with the isolated ORSV and/or CymMV. Results of back inoculation indicated that ORSV is the sole causal agent of the crinkle symptom on petals of Phalaenopsis orchid. The CP gene of the ORSV isolates from this study shared 97.3–100% nucleotide identity and 96.2–100% amino acid identity with those of 41 ORSV isolates available in GenBank. This is the first report demonstrating ORSV as the sole virus causing flower crinkle disease on Phalaenopsis orchids.     

Detection and identification of Clerodendron golden mosaic China virus in Salvia splendens

Two viral DNAs were obtained by rolling circle amplification conducted on DNA extracts from salvia (Salvia splendens) cv. ‘Dancing Flame’ showing variegated foliage resembling virus symptoms. Sequence analyses revealed the presence of an isolate of the putative begomovirus Clerodendron golden mosaic China virus. The virus was detected in all salvia plants showing variegated foliage, but not in non-variegated plants. The virus was graft-transmitted to healthy salvias which reproduced the original symptoms. Attempts to transmit the virus with the whitefly Bemisia tabaci biotype B failed. The results of this investigation strongly suggest that the salvia isolate of Clerodendron golden mosaic China virus (ClGMCNV-Sal[USA:LA:11]) is the cause of the variegated foliage of S. splendens cv. ‘Dancing Flame’. This is the first report of this virus in the United States.     

Study of variegated and white flower petals of Capparis spinosa expanded at dusk in arid landscapes

In this study,we provide the first evidence of two pairs of petals of the rapidly expanded and short-lived nocturnal flowers of Capparis spinosa L.(caper)during the prolonged drought period in Eastern Mediterranean region.The corolla of the winter-deciduous,perennial C.spinosa consists of two pairs of petals:a pair of white distinct petals and a pair of connate variegated petals with green basal parts.The results indicated the presence of substantially different amounts of chlorophyll in the two pairs of petals,while their carbohydrates’content is comparable with that of the green sepals.High resolution imaging of petal surfaces of short-lived flowers of C.spinosa, obtained by using scanning electron microscopy,revealed stomata on the adaxial epidermis on both the white and the green parts of the variegated petals;while dense hairs were found on the surface of the abaxial green parts of the variegated petals.Adaxial,epidermal cells of the variegated petals,viewed using atomic force microscopy,possess a submicron,cuticular microfolding that differs between the white and the green parts of the petals.It appears that microridges on the adaxial,white parts of petals of C.spinosa compensate for an increase in cell surface area of the short lived petals,while the roughness of the green parts of petals was found to be higher than that of the white parts.Thus,the micromorphology of surfaces of epidermal cells is expected to affect optical properties and wettability of the floral tissues.These findings may be particularly important for understanding the performance of the short-lived petals of C.spinosa,which are exposed to dryland environments.     

西花蓟马传播病毒病的研究进展

西花蓟马［Frankliniella occidentalis (Pergande)］是一种世界性的重要农业害虫,目前在69个国家和地区已有报道。西花蓟马能以持久性的方式传播番茄斑萎病毒属(Tospovirus)的病毒,所传播病毒造成的经济损失远远大于其本身所造成的损失。因此,许多学者对西花蓟马及其传播的番茄斑萎病毒属病毒进行了大量研究。本文主要综述了近年来西花蓟马传播病毒的种类、番茄斑萎病毒属病毒的结构以及西花蓟马的传毒机制等方面的研究进展。