北京辣椒和番茄上番茄斑萎病毒的鉴定

北京大兴区某蔬菜种植基地的辣椒和番茄发现疑似病毒感染,造成较大经济损失.经症状分析和RT-PCR检测,证实其感染番茄斑萎病毒(tomato spotted wilt virus,TSWV).基于TSWV序列特征对该地区TSWV进化及来源进行分析,结果显示其与北京顺义区已经报道TSWV毒株进化关系较近,但较国内其他地区株...     

北京地区侵染茄子的番茄斑萎病毒分子鉴定与分析

调查发现北京地区一温室栽培茄子Solanum melongena L.出现严重病毒病。利用基于小RNA的高通量测序技术和RT-PCR方法,明确了引起茄子病害的病毒种类为番茄斑萎病毒,将其命名为TSWV-eggplant分离物。进一步克隆了该病毒的基因组全长(S RNA、M RNA、L RNA),并构建其系统发育树。结果表明,该分离物的S RNA与美国分离物亲缘关系较近,M RNA与中国分离物亲缘关系较近,而L RNA与韩国分离物亲缘关系较近。因此,本研究发现的TSWV分离物与国内已发生报道的分离物不同,该分离物是否存在不同分离物之间基因组的重组需要进一步研究。     

青蒿中番茄斑萎病毒和烟草花叶病毒的分子鉴定及相关序列分析

番茄斑萎病毒(tomato spotted wilt virus, TSWV)和烟草花叶病毒(tobacco mosaic virus, TMV)是2种重要的植物病原病毒, 对多种经济作物的产量和品质均造成严重影响。2021年-2022年, 在云南省丽江市烟草种植区不同烟区采集叶片黄化、皱缩以及无症状的青蒿Artemisia caruifolia样品共计14份, 利用免疫金标速测卡和RT-PCR对其病原病毒进行检测。利用免疫金标速测卡检测结果显示, 在所检样品中有9份样品检测出TSWV, 检出率为64.28%, 有3份样品检测出TMV, 检出率为21.43%, 2种病毒复合侵染的检出率同样为21.43%;利用RT-PCR对复合侵染的3份样品进行分子检测, 结果显示, 在3份复合侵染青蒿样品中获得3条TSWV N基因序列、3条TMV cp基因序列和2条TMV RdRp部分序列。TSWV青蒿分离物与分离自云南的TSWV-2分离物相似性最高, 为99.6%;TMV青蒿分离物与分离自辽宁的TMV-Shenyang分离物和分离自云南的TMV-Yongren-1相似性最高, 均大于99.4%。这是首次发现TSWV和TMV 2种不同属病毒复合侵染青蒿。     

Assessing the susceptibility of chrysanthemum cultivars to tomato spotted wilt virus

Three methods were compared to assess the susceptibility of vegetatively propagated chrysanthemum to tomato spotted wilt tospovirus (TSWV): mechanical and thrips-mediated inoculation of whole plants, and a leaf-disc assay. As symptom expression was often poor or even absent, TSWV infections and subsequent susceptibility to TSWV were determined by ELISA. All 15 chrysanthemum cultivars tested were susceptible to TSWV, irrespective of their degree of vector resistance (based on feeding-scar damage rates). Thrips-mediated inoculation using different numbers of thrips revealed that 100% infection was obtained when plants were challenged by six thrips per plant, whereas 80 and over 50%, respectively, of the plants became infected when inoculated by a single male or female thrips. However, false negatives were scored even after intensive sampling because of erratic, cultivar-specific and time-dependent virus distribution after inoculation in the plants. Labour-intensive samplings and long incubation periods could be overcome by a readily applicable leaf-disc assay. This assay was as reliable as thrips-mediated inoculation of whole plants, and its use is therefore favoured to assess chrysanthemum cultivars for TSWV susceptibility.     

Genetics of tomato spotted wilt virus resistance coming from Lycopersicon peruvianum

New resistance sources coming from Lycopersicon peruvianum, especially those introgressed in UPV 32 line, are studied. UPV 32 resistance is controlled by a single gene. Resistance and dominance levels of this gene are conditioned by thrips transmission and isolate aggressiveness. A partial overcoming of resistance occurs due to the incomplete penetrance of the gene. Incomplete dominance of resistance also happens, which suggests gene dosage dependence. UPV 32 gene segregates independently of both Sw-5 gene and UPV 1 resistance gene, also coming from Lycopersicon peruvianum. It is proposed to name Sw-6 this new locus from UPV 32. Sw-5 gene and UPV 1 resistance gene show higher resistance than Sw-6. Heterozygotes for UPV 1 resistance gene were more resistant than heterozygotes for Sw-5. The lower dependence of UPV 1 resistance gene on the gene dosage effect makes it very useful for the development of commercial hybrids.     

Detection of tomato spotted wilt virus and transmission by Frankliniella occidentalis in France

Tomato spotted wilt virus (TSWV) was isolated from pepper, tomato, eggplant, broad bean, lettuce, basil, chrysanthemum, aster, New Guinea impatiens, anemone and gloxinia plants. Virus identification was based on host range, vector transmission, serology and electron microscopy. TSWV was readily detected by ELISA in naturally or artificially infected cultivated or weed plants. The virus was also detected in individual F. occidentalis thrips. The spread of TSWV in vegetable and ornamental plants in greenhouses and/or in the open is related to the close relationship of the virus with the vector.     

由美国进境生菜种子上番茄斑萎病毒的检测鉴定

采用DAS-ELISA检测方法,从美国进境的生菜种子中筛选出携带有番茄斑萎病毒(Tomato spotted wilt virus,TSWV)的疑似阳性样品,通过建立的RT-PCR方法对酶联免疫吸附测定阳性样品进行复核鉴定,并进一步测序。测序结果与GenBank中已有的番茄斑萎病毒分离物KT160282、AY744474、GU369726、KP330470的序列同源性达到96%。结果表明,TSWV可通过种子携带入境。     

Ornamental plants and thrips populations associated with tomato spotted wilt virus in Greece

A survey was conducted in order to record the ornamental plants that are hosts of tomato spotted wilt virus (TSWV) and impatiens necrotic spot virus (INSV) in Greece. Polyclonal antibodies prepared against the N protein of a Greek isolate of TSWV fromGerbera jamesonii (GR-34) were used. Leaf samples were taken from plants showing typical symptoms of tospovirus infection such as chlorotic and necrotic rings on the leaves and malformation and necrosis of the flowers. The samples were tested by double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using polyclonal antibodies to the N proteins of TSWV and INSV (NL-07). ELIS A-positive samples were mechanically transmitted to plants ofPetunia hybrida, Nicotiana rustica andN. benthamiana to confirm infection. Although none of the samples was found infected with INSV, TSWV presence was recorded in 42 botanical species that belong to 40 genera in 27 families. Among them the speciesBeloperone guttata, Coleus barbatus, Impatiens petersiana andLilium auratum are reported for the first time as hosts of TSWV, whereasBegonia sp.,Catharanthus roseus Celosia cristata, Dianthus chinensis, Fuchsia hybrida andStephanotis floribunda are found as new hosts of the virus in Greece. Thrips collected from TSWV-infected plants were in most cases identified asFrankliniella occidentalis, except from plants ofDendranthema sp. andDianthus caryophyllus whereThrips tabaci individuals were also identified. Different percentages of transmitters were noticed when the thrips populations collected from TSWV-infected ornamental hosts were tested for transmission of TSWV.     

A predictive model for spotted wilt epidemics in peanut based on local weather conditions and the tomato spotted wilt virus risk index

Tomato spotted wilt virus (TSWV), a member of the genus Tospovirus (family Bunyaviridae), is an important plant virus that causes severe damage to peanut (Arachis hypogaea) in the southeastern United States. Disease severity has been extremely variable in individual fields in Georgia, due to several factors including variability in weather patterns. A TSWV risk index has been developed by the University of Georgia to aid peanut growers with the assessment and avoidance of high risk situations. This study was conducted to examine the relationship between weather parameters and spotted wilt severity in peanut, and to develop a predictive model that integrates localized weather information into the risk index. On-farm survey data collected during 1999, 2002, 2004, and 2005 growing seasons, and derived weather variables during the same years were analyzed using nonlinear and multiple regression analyses. Meteorological data were obtained from the Georgia Automated Environmental Monitoring Network. The best model explained 61% of the variation in spotted wilt severity (square root transformed) as a function of the interactions between the TSWV risk index, the average daily temperature in April (TavA), the average daily minimum temperature between March and April (TminMA), the accumulated rainfall in March (RainfallM), the accumulated rainfall in April (RainfallA), the number of rain days in April (RainDayA), evapotranspiration in April (EVTA), and the number of days from 1 January to the planting date (JulianDay). Integrating this weather-based model with the TSWV risk index may help peanut growers more effectively manage tomato spotted wilt disease.     

An electron microscope study of tomato spotted wilt virus in the plant cell

Characteristic particles of about 70 m diameter were found in tomato spotted wilt virus (TSWV) infected cells of roots, stems, leaves and petals of several plant species. These particles were similar in size and form to those found in the pellets of partially purified infective TSWV.     

Resistance-breaking tomato spotted wilt orthotospovirus isolates on resistant tomato in Serbia

Journal of Plant Diseases and Protection - The most effective management strategy for tomato spotted wilt orthotospovirus (TSWV) has been the use of resistant tomato (Sw-5b+) cultivars....     

西花蓟马传播番茄斑萎病毒研究进展

西花蓟马Frankliniella occidentalis是世界性重要检疫性害虫之一,不仅直接取食危害作物而且传播病毒,从而造成极为严重的经济损失。由于西花蓟马在我国具有广泛的适生范围,随其入侵我国并随之传播的番茄斑萎病毒(Tomato spotted wilt virus)已在我国不同地域发现,对经济作物已形成严重威胁。本文综述了西花蓟马对番茄斑萎病毒的获取、携带和传播扩散过程及其病毒在蓟马体内的循环过程和机理,总结了影响西花蓟马传播番茄斑萎病毒效率的因素,并评述了西花蓟马-病毒-植物这一互作系统及其对西花蓟马生长发育适合度的影响,以期为我国西花蓟马传播番茄斑萎病毒的基础研究和防控提供理论依据与指导。     

Biological and molecular characterization of tomato spotted wilt virus (TSWV) resistance-breaking isolates from Argentina

Tomato spotted wilt virus (TSWV) has been present in Argentina since 1938 and had limited sweet pepper and tomato production until the introduction of resistant cultivars bearing Tsw and Sw-5b genes. However, the wide use of TSWV-resistant pepper plants in La Plata Horticultural Belt (LPHB) triggered the emergence of resistance-breaking isolates (RB), increasing the economic impact of TSWV in pepper. This work characterized 11 natural RB pepper isolates from LPHB that have overcome the Tsw resistance gene in Capsicum sp. but are unable to break the Sw-5b-mediated resistance in tomato. Phylogenetic analysis of the N gene showed that the LPHB isolates are most closely related to isolates from Asia, indicating that Argentine TSWV isolates might have emerged from the Asian continent. The NSs sequence analysis reinforces the hypothesis that the appearance of an RB phenotype is a consequence of a number of different single amino acid substitutions spread along the NSs gene that lead to multiple independent evolutionary events. These results provide information on the current situation of the tospovirus–pepper/tomato pathosystems in LPHB, which represents a fundamental prerequisite to include these RB isolates in future screening programmes in order to select new and durable sources of resistance to TSWV in pepper.     

Occurrence and characterization of tomato spotted wilt orthotospovirus isolated from cucumber

European Journal of Plant Pathology - Diseases associated with tomato spotted wilt orthotospovirus (TSWV) are a serious threat to vegetable production worldwide. In 2019, leaf necrosis disease was...     

Effect of temperature on symptom expression and accumulation of tomato spotted wilt virus in different host species

The effect of two temperature regimes (daytime, 29 ± 2°C, night-time, 24 ± 3°C; and daytime, 23 ± 1°C, night-time, 18 ± 2°C) on the symptoms caused by tomato spotted wilt virus (TSWV), and the accumulation of TSWV virions, was compared in Datura stramonium , Nicotiana tabacum cv. White Burley and Physalis ixocarpa . Tobacco plants were more severely affected by TSWV at the high temperature regime, but the incidence (percent of plants with symptoms) was 100% for both regimes. In P. ixocarpa and D. stramonium the higher temperature caused an increase in both incidence and rate of development of symptoms. At high temperature, all three species showed both local and systemic symptoms; however, at low temperature only P. ixocarpa consistently developed systemic symptoms. In general, virus accumulation in the inoculated leaves (presumably the combined effect of virus replication and local movement) of all plants was higher at the lower temperature. Long distance movement in tobacco, leading to virion accumulation in other plant organs, was favoured by high temperature; but there was relatively little effect in P. ixocarpa and D. stramonium .     

The proportion of viruliferous individuals in field populations of Frankliniella occidentalis: Implications for tomato spotted wilt virus epidemics in tomato

Tomato spotted wilt tospovirus (TSWV) infected plants and western flower thrips (Frankliniella occidentalis Perg., WFT) adult population densities were monitored during 1993 and 1994 in field tomatoes in Northeastern Spain. The proportion of viruliferous WFT adults in field populations was quantified. A significant association has been found between early population densities of WFT adult thrips and final TSWV incidence for early transplanted tomato crops. In contrast, for late transplanted tomato crops, whereas similar high final disease incidences of TSWV could be attained, very low WFT adult population densities were always detected. The significantly higher infectious potential of WFT populations collected during the early growth stages of late transplanted tomatoes could be relevant for the TSWV incidences attained in spite of the low thrips numbers detected.     

北京地区发现番茄斑萎病毒

通过采用特异快速试纸条以及进一步的RT-PCR和序列测定证实,在北京局部地区的辣椒和茄子上已发生番茄斑萎病毒,这两种作物上同时发生的蓟马种类主要为西花蓟马,并且携带该病毒。番茄斑萎病毒病是极其危险的一种病害,可对作物造成毁灭性灾害。建议有关部门立即采取相应的预防与管理措施,防止其扩散蔓延。