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1.
Growth and photosynthetic responses of invasive Bidens frondosa to light and water availability: A comparison with invasive and native congeners 
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下载免费PDF全文 Bidens frondosa is a new invasive species in China. However, the mechanisms underlying its invasiveness are still not understood. This study compared the new invader with its invasive congener, Bidens pilosa, and two native congeners, Bidens biternata and Bidens tripartita, in terms of their morphology, growth, biomass allocation and photosynthetic parameters across variant light and water conditions, aiming to explore the traits that are associated with the invasiveness of the invasive species. All these species are annual herbs. The results showed that the four congeners had a similar tendency of plasticity in their morphological and growth traits to varying light and water, but their response was quantitatively different. Most of the morphological and growing variables, as well as the photosynthetic parameters, were affected more strongly by manipulated light levels. Although B. frondosa had a lower total biomass and relative growth rate than the invasive congener, B. pilosa, the trait values related to growth (e.g. plant height, total biomass, relative growth rate and specific leaf area) and the mean value of the plasticity index were higher for the invasive B. frondosa than for the native B. tripartita. These could contribute to the invasiveness of the invasive species. In addition, the native species, B. biternata, is a vigorous weed with a strong adaptive capacity across various light and water gradients, suggesting that it has the potential to be invasive if introduced into areas with suitable conditions for growth. 相似文献
2.
The establishment of invasive species is widely recognised as a pivotal issue in the preservation of biodiversity. Salvia reflexa, a species native to the south‐central United States and Mexico, has been widely introduced in Argentina, Australia, New Zealand and Japan. In China, the first population of this plant was found growing adjacent to a grain depot in Shahai village, Jianping County, Liaoning Province, on 25 July 2007. Since the grain depot imported foodstuffs from regions where the plant is native, we infer that S. reflexa was introduced into China via imported foodstuff in the early to mid‐2000s. Based on field observations, at least seven populations of this plant were observed in north‐east China. The plants displayed vigorous growth in midsummer and produced prolific seeds to overcome the cold environment in winter. Salvia reflexa occurred in both dense monocultures and in mixed stands with native plants. In order to validate a system for recognising and categorising non‐native plants in China, the Australian Weed Risk Assessment system was used to assess the invasiveness status of 19 exotic and 16 native plants in north‐east China. Salvia reflexa exhibited a high score of 10, suggesting it is a potentially pernicious alien invasive plant. Although the current distribution of S. reflexa is restricted to Liaoning province and thus far has limited impact on local environments, local regulatory authorities should pay close attention to this plant and take measures to stop its expansion. This is the first time that an invasive plant from the Lamiaceae (mint family) has been documented from cold environments in China. 相似文献
3.
Performance of the invasive Eupatorium catarium and Ageratum conyzoides in comparison with a common native plant under varying levels of light and moisture 下载免费PDF全文
下载免费PDF全文 Qiaoqiao Huang Yide Shen Xiaoxia Li Zhiwei Fan Shaoliang Li Yan Liu 《Weed Biology and Management》2017,17(2):112-121
Invasive alien plants are often found to be more plastic than the natives, which enable the former to outperform the native plants under some, or in a wide range, of environmental conditions. In addition, their performance under non‐competitive conditions might not predict their performance under competitive conditions. The performance of the recent invader, Eupatorium catarium, was compared with that of a historical invader, Ageratum conyzoides, and a common native plant, Vernonia cinerea, under varying levels of light and moisture with and without competition. When grown alone and in response to decreases in light levels, E. catarium and V. cinerea were more plastic in their root‐to‐shoot ratio than A. conyzoides, while V. cinerea was more plastic in its specific leaf area (SLA) than E. catarium and A. conyzoides. Eupatorium catarium was more plastic than A. conyzoides and V. cinerea in the SLA in response to the drought treatment. However, these differences in trait plasticities did not lead to a difference in biomass production under each light and moisture treatment combination. When E. catarium was competing with either A. conyzoides or V. cinerea, the interacting species also did not differ in their biomass production and relative interaction intensity under each light and moisture treatment combination. These results indicate that the two invasive species and the native plant do not differ in their performance under relatively low soil nutrient conditions, regardless of the moisture, light and competition treatments that are imposed. Therefore, E. catarium and A. conyzoides cannot outperform V. cinerea under low nutrient conditions, regardless of the light and water availability. 相似文献
4.
This study presents a list of invasive alien plants that are found along roadsides in seven selected European countries – Austria, Germany, the Netherlands, Ireland, Norway, Slovenia and Sweden – and an overview on the role of roadsides as a habitat for invasive alien plants. This compilation is based on national lists of invasive alien plants, a literature search and expert consultation. Comprising 89 species from 31 plant families, species introduced for horticulture dominate the list (65%). Thirteen species (14%) are widespread (occur in four or more countries) and include well‐known invasive plants such as Fallopia japonica, Heracleum mantegazzianum, Solidago canadensis and Solidago gigantea. Seventeen species are listed either on the EPPO List of Invasive Alien Plants or on the EPPO A2 List of pests recommended for regulation as quarantine pests. Five species are on the List of Invasive Alien Species of Union Concern (EU Regulation 1143/2014). The compiled list provides a snap‐shot of invasive alien plants currently found along roadsides in the selected countries. It allows for a more targeted approach to monitoring, containment and control of the most problematic invasive alien plants identified in each country. Moreover, the list may also be used to identify emerging (potentially) invasive alien plants along roadsides in other European countries that warrant monitoring and/or management. 相似文献
5.
This study corrected the misidentification of an alien species, Salvia tiliifolia, which had been incorrectly identified as S. dugesii (a synonym of S. melissodora) in China. The distribution of S. tiliifolia in China was surveyed and it was inferred that it was probably introduced into Kunming, Yunnan in the 1990s and then spread to adjacent counties of Yunnan and south‐western Sichuan Province. The Australian weed risk assessment (WRA) was used to evaluate its invasive status. To determine the validity of Australian WRA in China, another 25 exotics representing casual alien plants, naturalised plants and invasive plants were tested. The Australian WRA was validated as a legitimate approach in China. Salvia tiliifolia scored 14, falling into the category of invasive plants. While the distribution of S. tiliifolia is currently restricted to Yunnan and a small part of Sichuan and the species has not displayed an adverse impact on local environments yet, the WRA results indicated that the species was a high risk plant. It was recommended that local land managers should monitor this species and take measures to stop its continuing expansion or eradicate it if possible. 相似文献
6.
Climate change is predicted to affect range expansion of harmful C4 weeds into the boreal region, given that they are able to successfully colonise both C3 and C4 crops. We studied the impact of a 3°C elevation in temperature on the establishment and maintenance of populations of two annual C4 weeds (Amaranthus retroflexus and Echinochloa crus‐galli) with and without a competing C3 (barley) or C4 (maize) crop. Data obtained from field and glasshouse experiments were modelled using a periodic matrix population model. Competition of a weed with a crop appeared to be a more important factor for limiting the maintenance of weed populations than elevation in temperature, as neither of the weed species was able to maintain populations in competition with crops. Even an increase in the frequency of warm years did not result in viable weed populations establishing. However, A. retroflexus was able to form persistent populations in competition with maize when released from competition every fifth year. Simulations parameterised from glasshouse data predicted that both weed species would persist without competition in the current climate, whereas simulations parameterised from field data suggested only A. retroflexus to be able to persist. These results demonstrate that competition affects the range expansion of arable weed species more than elevation in temperature, necessitating the inclusion of crop–weed interactions in models of range shifts as a consequence of climate change. 相似文献
7.
Can native grass species outcompete invasive goldenrods? Results of a replacement series experiment 下载免费PDF全文
下载免费PDF全文 Invasion by alien species is a serious threat to the biodiversity and function of semi‐natural grasslands and may impede restoration efforts in degraded meadows due to high competitiveness. Goldenrods (Solidago and Euthamia species) are considered among the most injurious invaders of grasslands in Central Europe. We tested the hypothesis that native grass species are able to outcompete the invasive goldenrods. A replacement series experiment was established to determine levels of interference between native grass taxa and goldenrods. In the experiment, four alien goldenrod species (Solidago altissima, Solidago canadensis, Solidago gigantea and Euthamia graminifolia) and one native species (Solidago virgaurea) were studied. The native grasses were represented by Lolium perenne (forage and turf varieties) and Festuca pratensis (forage variety). Total biomass was higher in the mixture of species compared with that in monoculture. The higher total biomass was due to higher productivity of the goldenrod species, whereas that of the grasses was reduced. These results demonstrated the high competitiveness of alien goldenrods compared with native grass species. 相似文献
8.
M. P. A. Coetzee N. Y. Musasira J. Roux F. Roets N. A. van der Merwe M. J. Wingfield 《Plant pathology》2018,67(4):883-891
Signs and symptoms of a disease similar to those of armillaria root rot have recently been observed on various native woody plants on the foothills of Table Mountain in South Africa, one of the most botanically diverse natural environments globally. This is of concern because the root rot fungus Armillaria mellea has previously been shown to be an alien pathogen of European origin in planted gardens in the City of Cape Town. An aim of this study was to identify the cause of the root rot disease on infected plants. Based on DNA‐sequence phylogeny, it was shown that isolates collected from at least 16 native tree and woody shrub species represented the non‐native A. mellea. Microsatellite markers were then used to determine the genetic diversity and population structure of the A. mellea isolates from Table Mountain and two planted gardens where the pathogen has previously been found. Population genetic analyses revealed low levels of gene diversity and no population differentiation amongst the three populations. The results provide the first firm evidence that A. mellea has escaped the planted environment and invaded a sensitive and ecologically important natural woody environment in South Africa. This is only the second definitive case of a non‐native tree pathogen invading a natural ecosystem in the country. 相似文献
9.
First release of a fungal classical biocontrol agent against an invasive alien weed in Europe: biology of the rust,Puccinia komarovii var. glanduliferae 下载免费PDF全文
下载免费PDF全文 The rust fungus Puccinia komarovii var. glanduliferae was first identified infecting Impatiens glandulifera in its native range (western Himalayas) between 2006 and 2010. Subsequently, it was imported into quarantine in the UK for evaluation as a classical biocontrol agent. To assess the safety of the rust, plant species relevant to Europe were tested for susceptibility. To confirm the life cycle, all infective spore stages were inoculated on I. glandulifera to follow disease progression. Teliospores were primed using bleaching and low temperatures to break dormancy. Temperature and dew period experiments using urediniospores were conducted to assess the parameters required for infection. Of the 74 plant species tested, only I. balsamina, an ornamental species, was fully susceptible to urediniospore inoculum. The life cycle of the rust – an autoecious, full‐cycled species with five spore stages – was confirmed. Urediniospores were infective between 5 and 25°C, with an optimum at 15°C. A minimum of 8 h dew period was required to achieve consistent infection. Based on a pest risk assessment, the rust poses no threat to native biodiversity within EU Member States; making P. komarovii var. glanduliferae a suitable candidate as the first fungal classical biocontrol agent against an exotic weed in the region. 相似文献
10.
Competitive traits of the invasive grass Arundo donax are enhanced by carbon dioxide and nitrogen enrichment 下载免费PDF全文
下载免费PDF全文 Increased atmospheric carbon dioxide (CO2) and soil nitrogen (N) may confer competitive advantages to invasive species over native plant species. We conducted a two‐way factorial experiment, growing the model invasive plant Arundo donax in CO2 growth chambers to test how CO2 and N availability interact to affect plant growth and biomass allocation. CO2 was supplied at c. 400 mg L?1 and c. 750 mg L?1. N was supplied as ammonium nitrate at 640, 320 and 80 mg L?1. We hypothesised that the fertilisation effect of CO2 enrichment would offset limitations from N deficiency. The results indicated that A. donax plants grown with enriched CO2 and abundant N accumulated approximately 50–100% more biomass and allocated approximately 50% more biomass to rhizomes than plants grown under ambient CO2 conditions. Neither treatment affected the leaf area per unit mass (specific leaf area; SLA). Greater growth will likely increase A. donax's competitive potential, because increased rhizome biomass has been associated with increased stress tolerance and post‐disturbance resprouting capacity. The consistent SLA under all treatments suggests that A. donax has a morphological strategy that prioritises increasing leaf quantity over increasing individual leaves' photosynthetic potential. These results reveal the ecological strategies that contribute to the successful establishment, dominance and persistence of this invasive plant species. 相似文献
11.
Extended leaf phenology presents an opportunity for herbicidal control of invasive forest shrubs 下载免费PDF全文
下载免费PDF全文 For many of the shrub species invading temperate deciduous forests, extended leaf phenology contributes substantially to annual carbon gains, helping to make possible rapid growth and spread. We carried out a pair of proof‐of‐concept studies to evaluate the susceptibility of such shrubs to foliar herbicide treatment during the period of delayed senescence, i.e. well after it is typically attempted. We first evaluated leaf‐level physiology in four species that lose leaves late in autumn; photosynthetic rates were comparable (80–111%) to those reported for the same species in summer. While preliminary, this finding provides a strong indication that diverse shrub taxa remain susceptible to control into late autumn. In addition, we conducted a field trial involving one of these species (Lonicera maackii) to directly evaluate the effectiveness of foliar treatment in November; applications included glyphosate and two concentrations of aminocyclopyrachlor plus metsulfuron methyl. Treatments killed (72%) or severely injured (14%) target plants, inducing greater cambial damage in plants that retained greater fractions of their canopy or had smaller canopy widths; there were no statistically significant differences among application types. This study demonstrated that late autumn can be a viable period in which to treat weedy species that delay senescence strongly, such as the many invasive Lonicera species in North America. Given that climate change and urbanisation are further delaying senescence in invasive plant populations, our study serves as a call for further investigation into what promises to be an increasingly viable opportunity for weed control in deciduous forests. 相似文献
12.
为明确不同自然保护区外来入侵草本植物及其与本地植物多样性之间的关系,以我国生物多样性丰富的云南省为研究对象,于2014年对云南省6个国家级自然保护区的82个1 m2小样方(78个100 m2大样方)中外来入侵草本植物和本地植物物种丰富度和密度进行调查,并分析外来入侵草本植物物种丰富度与本地草本植物物种丰富度、外来入侵草本植物密度与本地草本植物密度的关系及对不同自然保护区外来入侵草本植物物种丰富度的差异进行分析。结果显示,共调查发现22种外来入侵草本植物,其中纳板河流域国家级自然保护区种类最多,达14种,金平分水岭国家级自然保护区仅有2种;6个国家级自然保护区本地草本植物的物种丰富度与外来入侵草本植物的物种丰富度之间、本地草本植物密度与外来入侵草本植物密度之间均呈现正、负2种相关关系,其中哀牢山国家级自然保护区本地草本植物的物种丰富度与外来入侵草本植物物种丰富度呈显著负相关,其它5个国家级自然保护区的相关性均不显著。简单回归分析表明自然保护区外来入侵草本植物物种丰富度与本地草本植物物种丰富度、本地草本植物盖度、本地乔灌木物种丰富度呈显著负相关,多元回归分析结果表明乔灌木物种丰富度和经纬度是造成不同自然保护区外来入侵草本植物物种多样性差异的主要原因。 相似文献
13.
Substantial heritable variation for susceptibility to Dothistroma septosporum within populations of native British Scots pine (Pinus sylvestris) 下载免费PDF全文
下载免费PDF全文 A. Perry W. Wachowiak A. V. Brown R. A. Ennos J. E. Cottrell S. Cavers 《Plant pathology》2016,65(6):987-996
The threat from pests and pathogens to native and commercially planted forest trees is unprecedented and expected to increase under climate change. The degree to which forests respond to threats from pathogens depends on their adaptive capacity, which is determined largely by genetically controlled variation in susceptibility of the individual trees within them and the heritability and evolvability of this trait. The most significant current threat to the economically and ecologically important species Scots pine (Pinus sylvestris) is dothistroma needle blight (DNB), caused by the foliar pathogen Dothistroma septosporum. A progeny‐population trial of 4‐year‐old Scots pine trees, comprising six populations from native Caledonian pinewoods each with three to five families in seven blocks, was artificially inoculated using a single isolate of D. septosporum. Susceptibility to D. septosporum, assessed as the percentage of non‐green needles, was measured regularly over a period of 61 days following inoculation, during which plants were maintained in conditions ideal for DNB development (warm; high humidity; high leaf wetness). There were significant differences in susceptibility to D. septosporum among families indicating that variation in this trait is heritable, with high estimates of narrow‐sense heritability (0.38–0.75) and evolvability (genetic coefficient of variation, 23.47). It is concluded that native Scots pine populations contain sufficient genetic diversity to evolve lower susceptibility to D. septosporum through natural selection in response to increased prevalence of this pathogen. 相似文献
14.
Freckle disease of banana is caused by three closely related species of Phyllosticta, namely P. musarum, P. maculata and P. cavendishii. In this study, a high resolution melting (HRM) analysis assay was developed and its potential to identify these three fungal species is reported. The assay, which targets the ITS of the nuclear rDNA of the fungal species, generates three distinct melt profiles for the three Phyllosticta species. It is also able to distinguish a combination of up to three co‐infecting species by generating a deviant melt curve. Thirty‐five fungal cultures and infected herbarium leaf specimens, previously characterized using nucleotide sequencing as belonging to one of the three Phyllosticta species, were used for validation of the HRM analysis assay. The normalized curves generated differentiated all samples, with samples from each species correctly identified. The assay was further evaluated against 18 uncharacterized infected leaf specimens from various geographic locations and the results were verified by subsequent nucleotide sequencing. This HRM analysis assay allows rapid identification and differentiation of the three Phyllosticta species using a single primer pair in a one‐step closed‐tube system without labelled fluorescence probes. This novel assay format has potential for simultaneously identifying and differentiating other closely related species of plant pathogens, as well as the classification of infected historic specimens. 相似文献
15.
Microsatellite and mating type markers reveal unexpected patterns of genetic diversity in the pine root‐infecting fungus Grosmannia alacris 下载免费PDF全文
下载免费PDF全文 T. A. Duong Z. W. de Beer B. D. Wingfield L. G. Eckhardt M. J. Wingfield 《Plant pathology》2015,64(1):235-242
Grosmannia alacris is a fungus commonly associated with root‐infesting bark beetles occurring on Pinus spp. The fungus has been recorded in South Africa, the USA, France, Portugal and Spain and importantly, has been associated with pine root diseases in South Africa and the USA. Nothing is known regarding the population genetics or origin of G. alacris, although its association with root‐infesting beetles native to Europe suggests that it is an invasive alien in South Africa. In this study, microsatellite markers together with newly developed mating type markers were used to characterize a total of 170 isolates of G. alacris from South Africa and the USA. The results showed that the genotypic diversity of the South African population of G. alacris was very high when compared to the USA populations. Two mating types were also present in South African isolates and the MAT1‐1/MAT1‐2 ratio did not differ from 1:1 (χ2 = 1·39, P = 0·24). This suggests that sexual reproduction most probably occurs in the fungus in South Africa, although a sexual state has never been seen in nature. In contrast, the large collection of USA isolates harboured only a single mating type. The results suggest that multiple introductions, followed by random mating, have influenced the population structure in South Africa. In contrast, limited introductions of probably a single mating type (MAT1‐2) may best explain the clonality of USA populations. 相似文献
16.
Xin Gao Yuanyuan Sun Yuehui Diao Yunpeng Zhao Rodríguez‐Leyva Esteban Guoqing Yang 《Weed Biology and Management》2020,20(2):61-68
In order to verify the escape‐from‐enemy hypothesis from the changes of nutrient substance and fitness of natural enemies on alien plants, contents of free amino acids in native and invasive plant populations of Ageratina adenophora and life history parameters of specialist herbivore Procecidochares utilis reared on these plants were investigated. Our results showed that the contents of glycine, valine, γ‐aminobutyric acid, proline, serine, alanine, and arginine in the invasive plants were higher than those in the native plants of A. adenophora. There was a shorter developmental duration and higher fecundity of P. utilis when fed on the invasive plants. The results indicated a possible fitness tradeoff of natural enemies between invasive and native plants arose from nutrient substance changes. 相似文献
17.
Chemical control of isolated invasive conifers using a novel aerial spot application method 下载免费PDF全文
下载免费PDF全文 Conifer species, which have formed the foundation of commercial forestry industry in many countries, are known to be invasive in natural ecosystems, especially in the Southern Hemisphere. Controlling isolated invasive conifers before they reach reproductive maturity is an essential element of any strategy that aims to reduce spread rate of these species. Using a novel helicopter‐mounted spot‐application gun, which delivers a precise dosage to the crown of each tree, the objective of this research was to test the efficacy of three triclopyr‐based treatments against the four most vigorous wilding conifer species (Pinus contorta, Pinus nigra, Pinus sylvestris and Pseudotsuga menziesii) under New Zealand field conditions. Herbicides tested were triclopyr at two different rates and a combination of triclopyr and picloram. Treated trees covered a wide range of heights (c. 0.5–16 m), and measurements of mortality taken two years post‐herbicide application were used to examine variation in efficacy of the herbicides. Successful treatment was defined by a mortality rate of 85% or higher. A logistic regression model was fitted to the mortality data and used to derive threshold tree heights at which 85% mortality occurred, H85. For all four species, the most effective treatment was application of 1000 ml of herbicide mixture per tree that contained 120 and 20 g, respectively, of the active ingredients triclopyr and picloram. There was a significant decline in efficacy of this treatment with increases in tree size for all four species. Values of H85 for this treatment were 7.4 m for P. nigra, 8.3 m for P. menziesii, 9.7 m for P. contorta and >10 m for P. sylvestris. The methods developed here could be used to effectively manage emerging conifer infestations before they become problematic. 相似文献
18.
Solidago canadensis is native to North America, but has become a noxious invasive plant in China. We know only a little about its invasion history and the effects of introductions on its genetic composition. Here, we investigated genetic variation and structure between 15 North American and 13 Chinese populations of S. canadensis using AFLP makers. Four AFLP loci suggested relatively high genetic diversity of this weed and similar genetic variation between the invasive range and the native range. Most genetic variation was within populations across two ranges, but the Chinese range had a higher degree of among‐population variation than the North American range. Multiple tests, including Bayesian assignment, UPGMA analysis, PCoA and analysis of ‘isolation by distance’, showed that the Chinese populations originated from at least two distinct native sources and that secondary introduction or dispersal should be common in China. Also, North American populations were possibly a single genetic group. Overall, S. canadensis in China was probably founded from multiple introductions and then spread through long‐distance dispersal associated with human activities. Genetic variability in the species in the invaded range appears to have favoured establishment and spread and may well provide a challenge to successful control. 相似文献
19.
Parthenium hysterophorus in Nepal: a review of its weed status and possibilities for management 下载免费PDF全文
下载免费PDF全文 The rapid expansion of the alien invasive Parthenium hysterophorus is a new agricultural and environmental problem for Nepal. Although the weed was first recorded in 1967, the most significant expansion has occurred in the last 20 years. The weed is thought to have entered Nepal from India and currently is found in the Tarai, Siwalik and hill regions of Nepal. A CLIMEX modelling projection has shown these regions to be climatically suitable for the growth of P. hysterophorus, both under the present and a future projected increased temperature. From the initially invaded roadside vegetation, the weed has now spread into cropping land and forests. Vehicle movement and transportation of agriculture products are the main means by which its seed is spreading. The weed has reduced plant species richness and changed species composition in grasslands, while fodder collectors have developed contact dermatitis from the plant. To date, no sustainable management strategy has been developed for this weed. However, the fortuitous arrival of the biological control agents Zygogramma bicolorata and Puccinia abrupta var. partheniicola has had some impact upon the weed's growth and abundance. A CLIMEX modelling projection identifies many suitable locations for Z. bicolorata outside of its present range and within areas where the weed is likely to spread, both under the present and under a future projected climate of increased temperature. Mapping of the currently invaded areas, management through community involvement and further releases of new and redistribution of current biological control agents are required to manage P. hysterophorus in Nepal. 相似文献
20.
Inoculation of Malus genotypes with a set of Erwinia amylovora strains indicates a gene‐for‐gene relationship between the effector gene eop1 and both Malus floribunda 821 and Malus ‘Evereste’ 下载免费PDF全文
下载免费PDF全文 T.W. Wöhner K. Richter G. W. Sundin Y. Zhao V. O. Stockwell J. Sellmann H. Flachowsky M.‐V. Hanke A. Peil 《Plant pathology》2018,67(4):938-947
The Gram‐negative bacterium Erwinia amylovora, causal agent of fire blight disease in pome fruit trees, encodes a type three secretion system (T3SS) that translocates effector proteins into plant cells that collectively function to suppress host defences and enable pathogenesis. Until now, there has only been limited knowledge about the interaction of effector proteins and host resistance presented in several wild Malus species. This study tested disease responses in several Malus wild species with a set of effector deletion mutant strains and several highly virulent E. amylovora strains, which are assumed to influence the host resistance response of fire blight‐resistant Malus species. The findings confirm earlier studies that deletion of the T3SS abolished virulence of the pathogen. Furthermore, a new gene‐for‐gene relationship was established between the effector protein Eop1 and the fire blight resistant ornamental apple cultivar Evereste and the wild species Malus floribunda 821. The results presented here provide new insights into the host–pathogen interactions between Malus sp. and E. amylovora. 相似文献