苏南五地(市)主要蔬菜作物的病毒种类、区域分布和发生趋势

苏南地处我国东南沿海长江三角州中心.为明确该地蔬菜作物病毒病种类和发生趋势,采用分子生物学核酸检测的方法,对2018年5月至2019年12月,采自江苏南京、无锡、镇江、苏州和常州主要蔬菜作物的232份疑似病毒病样品进行检测鉴定,共检出12种病毒.其中,南京检出7种病毒,无锡检出4种,镇江检出2种,苏州检出6种,常州检出...     

Situation of glasshouse pests in Hungary1

The area of protected crops in Hungary is about 5300 ha. Most of it is under plastic, the area under glass being only about 250 ha. Vegetable growing makes up 80%, mostly on private farms. The main crops are capsicum, tomato and cucumber. On relatively small areas, ornamentals, principally cut flowers, are produced: carnation, gerbera, rose and chrysanthemum. The three most important, commonly occurring pests are Trialeurodes vaporariorum, Tetranychus urticae and aphids (Aphis gossypii, Myzus persicae, A. nasturtii). Polyphagotarsonemus latus, Liriomyza trifolii and Aculops lycopersici caused considerable economic damage during the eighties. However, in the last few years these pests have not been observed in any crops. Two new glasshouse pests have been described from ornamentals during the last 2 years in Hungary: Frankliniella occidentalis and Bemisia tabaci. Their accidental appearance in vegetable crops could lead to direct economic loss, besides endangering biological control systems.     

Tospoviruses infecting vegetable crops in Israel

Symptoms of vein clearing, stem necrosis, curling, necrotic spots and rings on the leaves associated with infection by tomato spotted wilt tospovirus (TSWV) were documented among vegetable crops growing in commercial glasshouses and open fields in Israel. Plants exhibiting symptoms were collected, from 1994-01 to 1998-12. Among cultivated vegetable crops analysed for TSWV by ELISA, the following plants were found to be infected: tomato, capsicum, aubergine, lettuce, cabbage and cucumber. These incidences of the virus were all correlated with the occurrence in high population of Frankliniella occidentalis. Transmission of the virus from infected Datura stramonium to Petunia leaf discs, by F. occidentalis , was up to 26%. TSWV antigens were readily detected by ELISA in seeds harvested from naturally infected vegetable crops. However, we failed to show virus transmission to the progeny plants. Iris yellow spot tospovirus (IYSV) was detected in onion. High incidence of the disease was associated with large populations of Thrips tabaci.     

Distribution and fitness of isolates of Botrytis cinerea with multiple fungicide resistance in Spanish greenhouses

Forty-nine greenhouses of vegetable crops were surveyed in southeast Spain at the beginning of the disease season in December 1992 to estimate frequencies of resistance to benzimidazoles, dicarboximides and N -phenylcarbamates (NPC) in B. cinerea . Out of 261 isolates collected, 28% were sensitive to both benzimidazoles and dicarboximides, 15% were benzimidazole-resistant and dicarboximide-sensitive, 8% were benzimidazole-sensitive and dicarboximide-resistant and 46% were benzimidazole- and dicarboximide-resistant. Resistance to benzimidazole, dicarboximide and N -phenylcarbamate was determined by measuring the ability of each isolate to grow in the presence of carbendazim, procymidone and diethofencarb fungicides respectively. Carbendazim- or procymidone- resistant isolates were found in all surveyed greenhouses. Three isolates were found with resistance to carbendazim, procymidone and diethofencarb collected in two adjacent greenhouses that were sprayed with the carbendazim and diethofencarb mixture. All other isolates were sensitive to the mixture because they were either sensitive to carbendazim and resistant to diethofencarb or vice versa. Fitness of 31 isolates of B. cinerea was determined in vivo by measuring their sporulation and lesion growth rate on leaf disks. No fitness costs were associated with resistance to iprodione (dicarboximide) and benomyl (benzimidazole). Isolates with EC₅₀ values higher than 101 mg/L for benomyl and 1.6 mg/L for iprodione were considered to be field resistant (they caused visible lesions on cucumber leaf disks treated with each fungicide).     

干旱区甜瓜霜霉病远距离传播空间结构的初步研究

 经过9年在塔里木盆地边缘干旱区对伽师县等3个相互隔离的甜瓜霜霉病流行系统的实地调查研究,提出了甜瓜霜霉病远距离传播的三级空间结构。一个甜瓜霜霉病流行系统单元是在一个绿洲内,围绕可提供初侵染病原的黄瓜温室区而形成的,其空间结构分为区系(包含若干种植区)、种植区(包含若干田块)和田块三级结构。伽师甜瓜霜霉病流行区系分为3个种植区,甜瓜霜霉病每年春季最先从位于种植一区发生霜霉病的黄瓜温室附近的甜瓜开始发生,之后甜瓜霜霉病由近向远逐步传播。种植二区和种植三区甜瓜霜霉病的初发病时间(初发病中心出现的时间)比种植一区的分别平均晚20和45d,发病中心与初菌源地的平均距离分别是56.4和106.5km,表明此地甜瓜霜霉病菌远距离传播经历了从种植一区到种植二区,再从种植二区到种植三区的传播过程。     

泾惠渠灌区地下水位动态与灌溉农业的关系

基于大量实测资料,运用相关关系分析近50年来灌区地下水位动态和农业种植结构变化的关系等,研究地下水位对灌溉农业和气候条件变化的响应。研究表明:泾惠渠灌区实际灌溉面积从1958—1982年约8.2万hm2减少到1983—2000年约4.87万hm2,同时粮食作物种植比例逐渐从70%上升到95%,近20年来,蔬菜种植面积不断增加,当前已经达到作物种植面积的25%左右;1983年之前,随作物种植面积的增加地下水位变化不大,1983年之后灌区蔬菜播种面积剧增,蔬菜种植面积每增加1万hm2,地下水位降幅为3.5 m;同时地下水位下降还受蒸发强度、工业用水等因素的影响。     

Occurrence and incidence of viruses infecting green beans in south-eastern Spain

A study was conducted to determine the identity and prevalence of viruses in 455 greenhouses in the main Spanish green bean growing area. Directed surveys were conducted in 422 crops from 2000–2004 to collect samples from diseased plants displaying symptoms that could be attributed to viruses. The samples were analysed to detect any virus by means of dsRNA extraction, mechanical inoculation to test plants, as well as ELISA and/or RT-PCR tests to detect potyviruses, geminiviruses and viruses previously known to infect beans in Spain. Random surveys were conducted in the years 2002 and 2005 (in 21 and 12 greenhouses, respectively) to study the actual incidence of known viruses in the area. Symptoms were recorded in 23,108 plants from which 664 plants were collected and analysed by ELISA or RT-PCR. The results of the directed surveys showed that all the analyzed crops carried the cryptic virus Phaseolus vulgaris endornavirus (PVuV), whereas phytopathogenic viruses appeared in smaller percentages of the crops: Tomato yellow leaf curl virus (TYLCV) 20.4%, Southern bean mosaic virus (SBMV) 9.0%, Tomato spotted wilt virus (TSWV) 4.0%, and the new species Bean yellow disorder virus (BnYDV) that broke out in 2004 with occurrence values higher than 34.3% that year. From 2000–2004 an important decrease in TYLCV was observed, along with a slight increase in SBMV and a consistently low occurrence of TSWV. The results of the random surveys confirmed the increased occurrence of virus detected during the directed surveys, and furthermore demonstrated the percentage of incidence for each virus.     

我国蔬菜作物重大入侵害虫发生、危害与控制

蔬菜是我国重要的经济作物,近年来外来入侵害虫给我国蔬菜生产造成了重大损失。本文以严重危害我国蔬菜作物的3类重大入侵害虫-烟粉虱、西花蓟马和斑潜蝇为例,从入侵昆虫的发现、种群鉴定、分布扩散趋势及其规律、灾变机制以及可持续治理技术体系的研究与应用等方面概述了我国蔬菜入侵害虫研究的主要成就。     

Compensation in seasonal leaf area dynamics and leaf longevity after defoliation in Buddleja davidii

Buddleja davidii is a major invasive weed and its success is attributed to its ability to recover rapidly following defoliation. To quantify the impacts of defoliation on seasonal leaf area dynamics, we measured rates of leaf area growth and loss on cohorts of leaves on control plants and on plants that were defoliated by 66% repeatedly at monthly intervals throughout two growing seasons. The rate of leaf area growth was closely related to cumulative air temperature, but the maximum rate for the defoliated plants in the first season was 2.2 times that of the control plants. This compensational leaf growth resulted in 52% greater total emergent leaf area, attributable to increased node production (34%) and leaf size (35%), compared with control plants. Leaf longevity during the first growing season in the defoliated plants was 12% greater than that in the control plants. During the second season, the degree of compensation was greatly reduced, attributable to reduced leaf size in defoliated plants compared with the control. Total emergent leaf area over both seasons in the defoliated treatment exceeded control values by only 15%. The impact of leaf loss on the vigour in this invasive shrub may, in the short term, be less significant than would be predicted. However, the impacts of continued defoliation are likely to increase markedly in subsequent years. The study provides the basis for modelling leaf area dynamics and plant growth in response to defoliation associated with biocontrol release programmes.     

徐州地区烟粉虱发生规律及治理措施初探

通过近2a观察表明,徐州地区烟粉虱在田间消长大致分4个阶段,成虫有4个主要迁移期;其喜干热、耐高湿的生活习性、冬季保护地栽培面积的扩大、外来虫源的传入及防治不力是烟粉虱种群数量累积并引起暴发的主要原因;主要寄主有9科20余种栽培作物;寄主植株上虫量垂直分布:棉花上部>中部>下部,温室蔬菜一般中、下部>上部。可采取严格检疫、清洁田园、轮作换茬、黄板诱杀、覆盖防虫网、保护和利用天敌、药剂防治等措施进行治理。     

Diversity,distribution and prevalence of vegetable-infecting geminiviruses in Burkina Faso

In West and Central Africa, as in many regions of the world, vegetables are severely affected by geminivirus diseases. In Burkina Faso, observation of various virus-like symptoms, especially on tomato, suggests the involvement of several geminiviruses and underlines the pressing need for additional information on their diversity, distribution, prevalence and host plant reservoirs. Large-scale surveys conducted in Burkina Faso confirmed the presence of tomato (yellow) leaf curl diseases (ToLCD-TYLCD) and geminiviruses in all localities with mean prevalences of 25% and 45%, respectively. Five geminiviruses including four begomoviruses (pepper yellow vein Mali virus (PepYVMLV), tomato leaf curl Burkina Faso virus, tomato leaf curl Mali virus and tomato leaf curl Ghana virus) and a dicot-infecting mastrevirus (chickpea chlorotic dwarf virus) were characterized on tomato. In addition, PepYVMLV and cotton leaf curl Gezira virus (CLCuGeV) were characterized on pepper and okra, respectively, in combination or not with alphasatellites and betasatellites for CLCuGeV. The most severe, prevalent and widely distributed virus on vegetables was PepYVMLV, which was characterized for the first time in combination with a genetically divergent DNA-B component that may constitute a key factor of PepYVMLV pathogenicity. Of the eight weeds identified as potential reservoir hosts of begomoviruses, four host PepYVMLV. The results confirm the importance of geminivirus diseases on vegetable crops in Burkina Faso and highlight the complex association of geminiviruses and satellites. The detection of begomoviruses in weeds growing close to crops points to the increasing necessity to consider reservoir plants and virus communities in the control of virus diseases.     

黄土区夏玉米叶面积指数变化规律的研究

通过对连续4a夏玉米叶面积指数的研究,建立了夏玉米叶面积指数与积温之间的归一化模型,提出了精确的且唯一确定的归一化方法。多年的叶面积动态变化用同一方程式表达,提高了方程的可信度,可用于作物生长模拟和作物生长监测和遥感估产。     

Biological and molecular characterization of Tomato spotted wilt Virus in Israel

Received April 24, 1997; received in final form June 29, 1997. Symptoms resembling tomato spotted wilt virus (TSWV) infections were documented among ornamental and vegetable crops in commercial greenhouses and open fields in Israel. Plants exhibiting these symptoms were collected from January 1992 to December 1996. Among cultivated plants analyzed for TSWV by enzyme-linked immunosorbent assay (ELISA), 19 species representing five families were found to be infected; natural infection was also recorded in six plant species of weeds. Virus identity was characterized by host range, serology and electron microscopy. Serological reaction with the isolates, found in Israel, using antisera from different sources as well as the sequence analysis of the nucleocapsid gene, demonstrated that the Israeli isolates of TSWV are a member of tospovirus serogroup I, type I (BR-01 strain). No virus transmission was found in seeds collected from virus-infected vegetable and ornamental crops. A non-radioactive molecular probe derived from the cloned nucleocapsid isolate enables specific detection of the virus in crude sap from infected plants. The detection of TSWV in Israel constitutes a severe potential threat to the ornamental and vegetable industry.     

Botrytis cinerea in greenhouse vegetables: chemical,cultural, physiological and biological controls and their integration

Botrytis cinerea is an ubiquitous pathogen which causes severe losses in many fruit, vegetable and ornamental crops. The pathogen infects leaves, stems, flowers and fruits. The complexity of diseases caused by B. cinerea in greenhouses makes this pathogen one of the most important diseases of vegetable crops in greenhouse in many countries. In general, epidemics occur in cool and humid conditions, which favour infection and may also predispose the host to become susceptible. High relative humidity in the greenhouse and free moisture on plant surfaces are considered the most important environmental factors which influence infection by B. cinerea. In this review we specify the factors affecting the development of diseases incited by B. cinerea and discuss different approaches for its suppression. Chemical and non-chemical controls are outlined and their integration is discussed. Finally, achievements, gaps in knowledge, and future needs are indicated. The most common means for disease management is by application of chemical fungicides. Both spraying of fungicides and application of fungicides directly to sporulating wounds is practiced. However, high activity of several fungicides is being lost, at least in part, due to the development of resistance. As fungicides still remain an important tool for control of epidemics caused by B. cinerea, it is important to monitor populations of the pathogen for their resistance towards potential fungicides. Cultural measures can be a powerful means to suppress plant diseases in greenhouses where the value of crops is high and the farmers make considerable efforts during long cropping seasons. Such measures are usually aimed at altering the microclimate in the canopy and around susceptible plant organs, prevention of inoculum entrance into the greenhouse and its build up, and, rendering the host plants less susceptible to diseases. Calcium loading of plant tissues and alteration of nitrogen fertilization reduce susceptibility to Botrytis. Cultivars resistant to B. cinerea are not available. Another alternative methods to control B. cinerea is by means of biological control agents. At least one preparation is already available in the market and in many cases it was as effective as the conventional fungicides. A decision support system was recently developed for integration of chemical and biological controls. Adaquate suppression of B. cinerea diseases in greenhouse crops is an attainable goal. In our opinion this goal can be reached by considering the ecology of the pathosystem in its broader sense and by integration of all possible control measures. This implies optimization of plant nutrition, microlimate and control (cultural, biological, physiological and, if necessary, chemical) measures. Moreover, Botrytis management must be incorporated in a more holistic system that is compatible with insect control, crop production systems and profitability of the crop.     

Regulation and use of biological control agents in Hungary

A wide range of biological control agents (BCAs) have been authorized and used in Hungary for the control of pests (including pathogens). BCAs are key elements of both integrated pest management and organic farming for different crops. Authorization of BCAs depends on the type of ‘active substance’. Micro‐organisms can be authorized under the EU Regulation (EC) No. 1107/2009 as plant protection products (PPP), while macro‐organisms are not within its scope. Plant protection tools (traps, mating disruption) are registered at a national level in Hungary, although mass traps and mating disruption pheromones are considered to be PPP. Plant extracts can be authorized as PPP, but some of them can be approved as a ‘basic substance’ and in this case they do not need further authorization. In Hungary, the vast majority of macro‐organisms used as BCAs have been mainly used in greenhouses and polytunnels for the control of thrips, whiteflies, aphids, leaf mining flies, phytophagous mites and lepidopteran pests in vegetable and ornamental crops. Recently a non‐indigenous chalcid wasp, Torymus sinensis, has been successfully introduced for the control of the oriental chestnut gall wasp, Dryocosmus kuriphilus, on chestnut (Castanea sativa) on different sites.     

Effects of soil and crop management practices and pedo‐hydrological conditions on the seedbank size of Galinsoga spp. in organic vegetable fields

Galinsoga quadriradiata and Galinsoga parviflora are very troublesome weeds in many organic vegetable crops in Europe. A very straightforward method to keep Galinsoga infestations under control is by targeting the Galinsoga seedbank. To identify cropping systems able to reduce the seedbank size in vegetable‐based cropping systems, the relationships between the seedbank size of Galinsoga species and prevailing soil/crop management practices and pedo‐hydrological conditions were investigated. Hereto, the seedbank of the 0–20 cm topsoil layer was sampled in 50 organic vegetable fields and analysed according to the seedling emergence method. Field history data were collected for the past 5 years, and physical, chemical and microbial soil quality was determined. Galinsoga quadriradiata was the most frequent and abundant Galinsoga species in the weed seedbank. The genus Galinsoga was present in 90% of the soil weed seedbanks of organic vegetable fields but displayed wide variation in abundance. Smallest Galinsoga seedbanks were found in fields that were predominantly tilled with non‐inversion implements or rotationally ploughed, and continuously cropped with competitive crops during the entire growing season (April 15‐November 15). Contrary to G. quadriradiata, seedbank size of G. parviflora was closely related to soil organic carbon content and sand fraction. Remarkably, soils with a low level of easily plant‐available phosphorus and concomitant high activity of arbuscular mycorrhizae had smaller G. quadriradiata seedbanks. To reduce Galinsoga infestations, fields should preferably be tilled without soil inversion, fertilised with organic amendments with low content of readily plant‐available phosphorus and cropped with competitive crops all season long.     

南繁水稻田杂草发生与化学防治

在我国冬季南繁育制种作物中,水稻所占面积最大,但是由于不同地域杂草群落组成的差异,继续沿用原产地的除草剂品种和技术后,除草效果并不理想甚至会造成水稻药害。为了解决此类问题,连续3年对南繁区水稻田冬季杂草发生情况进行调查,明确现用地的杂草种类与发生规律,分别按照杂草群落中禾本科、阔叶杂草和莎草科主要危害的种类指导科学合理地选择除草剂种类,避免盲目用药,从而实现减药又高效的除草目标。     

Occurrence of Corynespora cassiicola isolates resistant to boscalid on cucumber in Ibaraki Prefecture, Japan

A total of 651 isolates of cucumber corynespora leaf spot fungus ( Corynespora cassiicola ) collected from cucumber in Japan, either with (438 isolates) or without (213 isolates) a prior history of boscalid use, were tested for their sensitivity to boscalid by using a mycelial growth inhibition method on YBA agar medium. Additionally, seven isolates of C. cassiicola obtained from tomato, soybean, eggplant (aubergine) and cowpea in different locations in Japan were tested before boscalid registration. Minimum inhibitory concentration (MIC) and 50% effective concentration (EC₅₀) values for 220 isolates from crops without a prior history of boscalid use ranged from 0·5 to 7·5 μg mL⁻¹ and from 0·04 to 0·59 μg mL⁻¹, respectively. Two hundred and fourteen out of 438 isolates collected from ten cucumber greenhouses in Ibaraki Prefecture, Japan, which received boscalid spray applications showed boscalid resistance, with MIC values higher than 30 μg mL⁻¹. Moreover, resistant isolates were divided into two groups: a moderately resistant (MR) group consisting of 189 isolates with EC₅₀ values ranging from 1·1 to 6·3 μg mL⁻¹, and a very highly resistant (VHR) group consisting of 25 isolates with EC₅₀ values higher than 24·8 μg mL⁻¹. MR isolates were detected from all ten greenhouses, but VHR isolates were detected from only three. As a result of fungus inoculation tests which used potted cucumber plants, control failures of boscalid were observed against resistant isolates. Efficacy of boscalid was remarkably low against VHR isolates in particular. This is the first known report on boscalid resistance in Japan.     

Identifying obstacles and ranking common biological control research priorities for Europe to manage most economically important pests in arable,vegetable and perennial crops

EU agriculture is currently in transition from conventional crop protection to integrated pest management (IPM). Because biocontrol is a key component of IPM, many European countries recently have intensified their national efforts on biocontrol research and innovation (R&I), although such initiatives are often fragmented. The operational outputs of national efforts would benefit from closer collaboration among stakeholders via transnationally coordinated approaches, as most economically important pests are similar across Europe. This paper proposes a common European framework on biocontrol R&I. It identifies generic R&I bottlenecks and needs as well as priorities for three crop types (arable, vegetable and perennial crops). The existing gap between the market offers of biocontrol solutions and the demand of growers, the lengthy and expensive registration process for biocontrol solutions and their varying effectiveness due to variable climatic conditions and site‐specific factors across Europe are key obstacles hindering the development and adoption of biocontrol solutions in Europe. Considering arable, vegetable and perennial crops, a dozen common target pests are identified for each type of crop and ranked by order of importance at European level. Such a ranked list indicates numerous topics on which future joint transnational efforts would be justified. © 2016 Society of Chemical Industry     

Whiteflies on tomato crops in Portugal*

In Portugal during the 1960/1980s, there was intensive development of vegetable crop production, in particular protected crops, of which tomato was the most important. The main producing regions now are Ribatejo e Oeste, Alentejo and Algarve. Tomato presents extensive phytosanitary problems, being host to a wide range of pests, including the whiteflies Trialeurodes vaporariorum, in protected crops, and Bemisia tabaci, in protected and field crops. Portugal has applied for the status of an EU ‘protected zone’ for this latter pest. As B. tabaci is an important vector of a large number of viruses, including tomato yellow leaf curl viruses (TYLCV), a monitoring programme of the tomato crop was implemented in Portugal. Preliminary data are presented concerning B. tabaci in the three main tomato‐growing regions of the country.