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1.
Serap Mutun 《Phytoparasitica》2009,37(1):65-66
An invasive Tingidae, the platanus lace bug Corythucha ciliata (Say, 1832) (Hemiptera: Tingidae), which specializes on Platanus spp., was found for the first time in Turkey in 2007; it was recorded from a 120 km2 area in the northwestern part of the country. Infestations occurred in an area between Taşkesti and Abant in Bolu Province,
which is located near major cities and two main motorways. The pest species is newly spreading in Turkey, causing noticeable
damage to Platanus orientalis trees. 相似文献
2.
Akira Kawaguchi 《Journal of General Plant Pathology》2011,77(5):299-303
Forty-one strains of Rhizobium vitis, either tumorigenic (Ti) or nonpathogenic, were characterized using multilocus sequence analysis (MLSA) of the partial nucleotide
sequences of pyrG, recA, and rpoD. The strains separated into seven clades. Rhizobium vitis (Ti) strains isolated from Japan were divided into five genetic groups (A to E), and nonpathogenic R. vitis strains were divided into two genetic groups (F and G). This result suggests that there are new genetic groups of R. vitis in Japan. Among these groups, members of A and B groups are widely distributed throughout Japan. 相似文献
3.
Mathias De Backer Hossein Alaei Erik Van Bockstaele Isabel Roldan-Ruiz Theo van der Lee Martine Maes Kurt Heungens 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(3):325-338
Puccinia horiana is the causal agent of chrysanthemum white rust or Japanese rust. This microcyclic autoecious rust has a quarantine status
and can cause major damage in the commercial production of Chrysanthemum x morifolium. Given the international and often trans-continental production of planting material and cut flowers of chrysanthemum and
the decreasing availability of registered fungicides in specific regions, breeding for resistance against P. horiana will gain importance and will need to involve the appropriate resistance genes for the pathotypes that may be present. As
pathotypes have not been well characterized in this system, the main objective was to build an international collection of
isolates and screen these on a large collection of cultivars to identify different pathotypes. Using a robust and high throughput
bioassay, we tested 36 selected cultivars with 22 individual single-pustule isolates of P. horiana. The isolates originated from three different continents over 4 different collection years and included some isolates from
cultivars previously reported as resistant. In most cases the bioassays resulted in a clear scoring of interaction phenotypes
as susceptible or resistant, while in several cases consistent intermediate phenotypes were found, often on specific cultivars.
Twenty-four of the cultivars gave a differential interaction phenotype profile. All isolates produced a unique profile, infecting
a minimum of 4 and a maximum of 19 differential cultivars. Based on the Person analysis of these profiles, this pathosystem
contains at least seven resistance genes (and seven avirulence genes), demonstrating the highly complex race structure in
this pathosystem. 相似文献
4.
Márcia Silva Helena Machado Alan J. L. Phillips 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(3):425-433
Mycosphaerella leaf disease (MLD) is caused by species of Mycosphaerella and several anamorphic form genera that have been connected to Mycosphaerella. Until recently, MLD of eucalypts was largely ignored in Portugal. However, serious damage to Eucalyptus globulus has been reported since 1999 when frequent and severe defoliation of young trees was observed. The severity of this disease
prompted a preliminary study of the Mycosphaerella species associated with major symptoms of a leaf blotch disease in commercial plantations of E. globulus in Portugal, which is presented here. The species were identified by molecular methods based on the ITS1-5.8S-ITS2 cluster,
together with morphological characters. In addition to confirming the species previously recorded, Mycosphaerella vespa is reported for the first time from Portugal, while the status of Mycosphaerella grandis remains to be resolved. 相似文献
5.
Insect-borne viruses promote several changes in plant phenotype, which can modify plant-vector interactions in favor of virus survival and dissemination. Although co-infections commonly occur in the field, little is known about their effects on interactions with the vector. The ecological interactions between Barley Yellow Dwarf Virus (BYDV) and its aphid vector, Rhopalosiphum padi, have been investigated extensively, but the vector’s behavior in more complex scenarios has yet to be examined. We assessed olfactory response and performance of R. padi to wheat singly and doubly infected by the pathogenic fungus Giberella zeae and BYDV. Non-viruliferous aphids preferred odors of BYDV-infected wheat over healthy wheat, as previously reported in the literature, and they were still preferentially attracted to BYDV-infected plant during co-infection. However, around 35% more non-viruliferous aphids chose healthy wheat over G. zeae-infected wheat. Viruliferous aphids did not show any preference to the treatments. BYDV-infected wheat was a superior host than healthy wheat for the aphids whose population increased in 25%. We observed a synergistic effect of the co-infected wheat, which was the best host for aphids, and promoted an elevation of 42% on population growth. Our results indicate that co-infection might be beneficial for virus spread as does not interfere with aphid olfactory preference and provides greater colony growth than in singly infected plants. 相似文献
6.
Masamichi Isogai Koji Ishii Seisaku Umemoto Manabu Watanabe Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2009,75(2):140-143
Virus-like symptoms—red ringspots on stems and leaves, circular blotches or pale spots on fruit—were found on commercial highbush
blueberry (Vaccinium
corymbosum) cultivars Blueray, Weymouth, Duke and Sierra in Japan. In PCR testing, single DNA fragments were amplified from total nucleic
acid samples of the diseased blueberry bushes using primers specific to Blueberry red ringspot virus (BRRV). Sequencing analysis of the amplified products revealed 95.7–97.7% nucleotide sequence identity with the BRRV genome.
This paper is the first report of blueberry red ringspot disease caused by BRRV in Japan.
The nucleotide sequence data reported in this paper are available in the GenBank/EMBL/DDBJ database as accessions AB469884
to AB469893 for BRRV isolates from Japan. 相似文献
7.
Khalid Pervaiz Akhtar Muhmmad Yussouf Saleem Muhammad Asghar Mushtaq Ahmad Nighat Sarwar 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(4):435-450
Sixty-nine tomato genotypes representing nine Solanum species were evaluated for resistance to Cucumber mosaic virus (CMV) subgroup IA and its aphid vector Myzus persicae. Resistance was assessed by visual scoring of symptoms in the field under natural conditions, and in the greenhouse by artificial
inoculations through aphid M. persicae and mechanical transmissions in the year 2007 and 2009. Considerable variation in responses was observed among the evaluation
methods used. Field evaluations were found liable to errors as different levels were observed for the same genotypes in the
different years, however mechanical inoculation was found to be the most useful in identifying CMV subgroup IA resistance,
in contrast aphid transmission was most useful in identifying insect transmission resistance. All genotypes observed as highly
resistant to CMV subgroup IA in the field or through vector transmission became systemically infected through mechanical inoculations.
Using mechanical inoculation, six genotypes (TMS-1 of S. lycopersicum, LA1963 and L06049 of S. chilense, LA1353, L06145 and L06223 of S. habrochaites) were found resistant and another six (L06188 and L06238 of S. neorickii, L06219 of S. habrochaites, L05763, L05776 and L06240 of S. pennellii) were found tolerant showing mild symptoms with severity index (SI) ranging 1-2 and with delayed disease development after
a latent period (LP) of 18–30 days. However, these genotypes were found to be resistant to highly resistant in the field and
through inoculation by M. persicae; and they also supported low population levels of M. persicae except TMS-1. Another nine genotypes (LA2184 of S. pimpinellifolium L., LA2727 of S. neorickii, LA0111, L06221, L06127 and L06231 of S. peruvianum L., LA1306, L06057 and L06208 of S. chmielewskii) showing a susceptible response after mechanical inoculation were highly resistant, resistant and tolerant after M. persicae transmission. The resistant genotypes, identified in the present study can be exploited in the breeding programmes aimed
at developing tomato varieties resistant to CMV subgroup IA and broadening the genetic base of CMV-resistant germplasm. The
differences observed between mechanical and aphid transmission suggests that one should consider both evaluation methods for
tomato germplasm screening against CMV subgroup IA. 相似文献
8.
From the genome of a Japanese field isolate of the rice blast fungus, Magnaporthe oryzae, we newly identified Inago1 and Inago2 LTR retrotransposons. Both elements were found to be Ty3/gypsy-like elements whose copies were dispersed within the genome of Magnaporthe spp. isolates infecting rice and other monocot plants. Southern hybridization patterns of nine re-isolates derived from conidia
of the strain Ina168 produced after a methyl viologen treatment were not changed, indicating that the insertion pattern of
Inago elements is relatively stable. 相似文献
9.
Esmaeil Miraeiz Ramin Heydari Wim Bert 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):157-166
Phytophthora capsici infection of chili pepper seedlings can cause substantial losses due to damping-off and collar rot diseases. Chemical control is no longer effective due to reported resistance development, on top of the related environmental concerns and the consumer demands for reduced use of fungicides. Biological control is a sustainable option, with several agents having been reported to be effective against this pathogen. This research focused on optimizing the application of strain THSW13 of Trichoderma hamatum and a bacterial isolate BJ10–86 with the objectives of improving chili pepper seed germination, reduce damping-off disease incidence, and improve the growth of the seedlings. Bacterial isolate BJ10–86 was subjected to molecular identification and found to be Pseudomonas aeruginosa. Chili pepper seeds treated with the biocontrol agents, individually or in combination, were seeded into commercial nursery media that had been pre-inoculated with P. capsici zoospores. Over a period of 35 days the chili pepper seed treatments significantly (P = 0.008) reduced the disease incidence of seedlings damping-off. Combined application of T. hamatum and P. aeruginosa was the best biocontrol treatment with an area under disease curve of only 36.61 units compared to 92.87 units for the control treatment. Similar results were observed in vitro where T. hamatum and P. aeruginosa synergistically inhibited P. capsici growth by 73.2 %. The inhibition activity of this treatment was similar to mefenoxam treatment, which implies that it is an effective and sustainable alternative for chili pepper seed treatment. The biocontrol seed treatment had no effect on seed germination and seedling growth. 相似文献
10.
Khalid A. Hussein Mohamed A. A. Abdel-Rahman Ahmed Y. Abdel-Mallek Saad S. El-Maraghy Jin Ho Joo 《Phytoparasitica》2012,40(2):117-126
The greater wax moth Galleria mellonella L. (Lepidoptera: Pyralidae) is occasionally found in beehives and is a major pest of stored wax. Entomopathogenic fungi have
recently received attention as possible biocontrol elements for certain insect pests. In this study, 90 isolates of Beauveria bassiana and 15 isolates of Metarhizium anisopliae were screened for proteases and lipases production. The results showed significant variations in the enzymatic action between
the isolates. In the bioassay, the selected isolates evinced high virulence against the 4th instar of the G. mellonella larvae. The isolates BbaAUMC3076, BbaAUMC3263 and ManAUMC3085 realized 100% mortality at concentrations of 5.5 × 106 conidia ml−1, 5.86 × 105 conidia ml−1, and 4.8 × 106 conidia ml−1, respectively. Strong enzymatic activities in vitro did not necessarily indicate high virulence against the tested insect pest. The cuticle of the infected larvae became dark
and black-spotted, indicating direct attack of fungus on the defense system of the insects. The LC50 values were 1.43 × 103, 1.04 × 105 and 5.06 × 104 for Bba3263AUMC, Bba3076AUMC and Man3085AUMC, respectively, and their slopes were determined by computerized probit analysis
program as 0.738 ± 0.008, 0.635 ± 0.007 and 1.120 ± 0.024, respectively. 相似文献
11.
Susceptibility of eggs of Tribolium confusum du Val. (Coleoptera: Tenebrionidae), Ephestia kuehniella (Zell.) (Lepidoptera: Phycitidae) and Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) to vapors of essential oil from garlic (Allium sativum L.), birch (Betula lenta L.), cinnamon (Cinnamonum zeylanicum (Blume)) and aniseed (Pimpinella anisum L.) was studied. Preliminary bioassay tests indicated that vapors of the essential oils had a significant effect on the eggs
of tested insect species when exposed to a concentration of 20 μl l
−1 air for 24 h. Generally, garlic and birch essential oils were more toxic to the eggs of tested insect species than cinnamon
and aniseed essential oils (except for eggs of T. confusum). There was also a significant difference between susceptibility of eggs of T. confusum, E. kuehniella and P. interpunctella to tested essential oils. Toxicity data indicated that eggs of T. confusum were more susceptible to tested essential oils, with LC90 values ranging from 3.11 to 33.49 μl l
−1 air, than those of E. kuehniella and P. interpunctella; eggs of P. interpunctella were the most tolerant to the essential oils, with LC90 values ranging from 22.02 to 72.42 μl l
−1 air. Concentration × time (Ct) products of 0.29, 0.22, 0.13 and 1.37 mg h l
−1 for garlic, birch, cinnamon and aniseed essential oil, respectively, were required to obtain 90% kill of T. confusum eggs. Although cinnamon essential oil had a much closer Ct product value to methyl bromide, garlic and birch essential oils
were found to be the most promising ones since they had also high fumigant toxicity on eggs of both E. kuehniella and P. interpunctella. 相似文献
12.
The effects of some fungicides used against citrus diseases, on mycelial growth and conidial germination of Isaria farinosa (Holmsk.) Fries [Sordariomycetes: Hypocreales] and also on the pathogenicity of the fungus on citrus mealybug, Planococcus citri (Risso), were determined. Systemic fungicides such as tebuconazole, penconazole and nuarimol were the most effective as regards
both conidial germination and mycelial growth. Protective fungicides such as captan, chlorothalonil, mancozeb and propineb
inhibited conidial germination at between 1 and 5 μg ml−1 concentration, but captan, chlorothalonil and propineb did not inhibit the mycelial growth at 5,000 μg ml−1. Mancozeb inhibited mycelial growth between 2,500 and 5,000 μg ml−1. Sulphur and copper oxychloride did not inhibit the fungus even at very high concentrations. Sulphur, copper oxychloride,
fosetyl-al, chlorothalonil and carbendazim did not decrease the mortality percentage caused by I. farinosa. Tebuconazole, penconazole and mancozeb were the most effective and respectively reduced the mortality from 83% to 33%, 28%
and 30% in the ovisacs, from 81% to 29%, 27% and 29% in the 1st instar larvae, and from 84% to 34% in the adult females. 相似文献
13.
Zonate leaf spot (Gloeocercospora sorghi) is a common disease in Sorghum bicolor producing areas of the U.S., but little is known about its biology, virulence and severity on S. bicolor, Zea mays, and related crop grassweeds. Greenhouse studies were conducted to determine and compare the virulence and severity of G. sorghi on 10 commercially available sorghum hybrids, four Z. mays hybrids and selected grassweed species including Sorghum bicolor (grain sorghum and shattercane biotypes) and Sorghum halepense (Johnsongrass), two of the most problematic arable weeds. Plants from the respective species were inoculated with a local G. sorghi isolate and maintained in a dew-chamber at 24 °C for 24 h and then incubated under greenhouse conditions for 4 weeks. Plants were observed for lesion expression and rated using a modified Horsfall-Barrett scale (0–10). The first symptoms of infection were visible within 24 h following inoculation on shattercane and S. bicolor hybrids. Symptoms consisted of small, non-diagnostic purple lesions on the leaves. Results showed that S. bicolor, S. halepense and shattercane were susceptible to G. sorghi. All other species tested in this study were not infected. More particularly, disease severity, increased from a rating of 3 to 10 on sorghum and from 2 to 7 on S. halepense between 2 and 23 days after inoculation, respectively. However, disease severity on shattercane increased rapidly from 3.5 to 10 between 2 and 8 days after inoculation, respectively. Among the sorghum hybrids tested, FFR-322 appeared to be the most resistant to G. sorghi while Pioneer 83G66 appeared to be the most susceptible. Z. mays hybrids were not infected by the fungus used in this study. G. sorghi could be used effectively to manage shattercane and S. halepense infestations occurring in Z. mays and S. bicolor fields consisting of specific G. sorghi-resistant hybrids. 相似文献
14.
Eisse G. de Haan Toos C. E. M. Dekker-Nooren Gé W. van den Bovenkamp Arjen G. C. L. Speksnijder Patricia S. van der Zouwen Jan M. van der Wolf 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(4):561-569
It is well established that the pectinolytic bacteria Pectobacterium atrosepticum (Pca) and Dickeya spp. are causal organisms of blackleg in potato. In temperate climates, the role of Pectobacterium carotovorum subsp. carotovorum (Pcc) in potato blackleg, however, is unclear. In different western and central European countries plants are frequently
found with blackleg from which only Pcc can be isolated, but not Pca or Dickeya spp. Nevertheless, tubers vacuum-infiltrated with Pcc strains have so far never yielded blackleg-diseased plants in field
experiments in temperate climates. In this study, it is shown that potato tubers, vacuum-infiltrated with a subgroup of Pcc
strains isolated in Europe, and planted in two different soil types, can result in up to 50% blackleg diseased plants. 相似文献
15.
Shigemitsu Kimura Susumu Tokumaru Kazuhiko Kuge 《Journal of General Plant Pathology》2009,75(4):322-324
Yeast-like fungi were isolated from lesions on azuki bean (cv. Shin-Kyotodainagon) seeds that had been sucked by bean bugs
in Kyoto Prefecture, Japan. On the basis of morphological and physiological characteristics and sequence data of the internal
transcribed spacer (ITS) regions including the 5.8S rDNA, these yeasts were identified as Eremothecium coryli and E. ashbyi. Pathogenicity of those yeasts was confirmed by a reinoculation test. To our knowledge, this is the first report of the occurrence
of yeast spot in azuki bean in Japan.
The nucleotide sequence data reported are available in the GeneBank/EMBL/DDBJ database as accessions AB478291–AB478309 for
E. coryli AZC1–19 and AB478310–AB478317 for E. ashbyi AZA1–8. 相似文献
16.
Fabian Runge Young-Joon Choi Marco Thines 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(2):135-146
Pseudoperonospora cubensis is one of the most devastating diseases of cucurbitaceous crops. The pathogen has a worldwide distribution and occurs in
all major cucurbit growing areas. It had been noticed for the first time at the end of the 19th century, but it became a globally
severe disease as recently as 1984 in Europe and 2004 in North America. Despite its economic importance, species concepts
in Pseudoperonospora are debated. Here, we report that the genus Pseudoperonospora contains cryptic species distinct from the currently accepted ones. Pseudoperonospora on Celtis is split into two phylogenetic lineages and Pseudoperonospora humuli is confirmed as a species distinct from the Cucurbitaceae-infecting lineages. A cryptic species occupying a basal position
within the Pseudoperonospora cubensis complex is revealed to be present on Humulus japonicus, thus providing evidence that the host jump that gave rise to Pseudoperonospora cubensis likely occurred from hops. Notably, Cucurbitaceae infecting pathogens are present in two cryptic sister species or subspecies.
Clade 1 contains primarily specimens from North America and likely represents Pseudoperonospora cubensis s.str.. Pre-epidemic isolates in clade 2 originate from Japan and Korea, suggesting this cryptic species or subspecies is
indigenous to East Asia. Recent samples of this lineage from epidemics in Europe and the United States cluster together with
clade 2. It thus seems possible that this lineage is associated with the recent severe epidemics of cucurbit downy mildew
and is now naturalised in North America and Europe. 相似文献
17.
Alireza Akhavan T. Kelly Turkington Berisso Kebede Kequan Xi Krishan Kumar Andy Tekauz H. Randy Kutcher James R. Tucker Stephen E. Strelkov 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(2):325-336
Infection by Pyrenophora teres f. teres (Ptt) or P. teres f. maculata (Ptm), the causal agents of the net and spot forms of net blotch of barley, respectively, can result in significant yield losses. The genetic structure of a collection of 128 Ptt and 92 Ptm isolates from the western Canadian provinces of Alberta (55 Ptt, 27 Ptm), Saskatchewan (58 Ptt, 46 Ptm) and Manitoba (15 Ptt, 19 Ptm) were analyzed by simple sequence repeat (SSR) marker analysis. Thirteen SSR loci were examined and found to be polymorphic within both Ptt and Ptm populations. In total, 110 distinct alleles were identified, with 19 of these shared between Ptt and Ptm, 75 specific to Ptt, and 16 specific to Ptm. Genotypic diversity was relatively high, with a clonal fraction of approximately 10 % within Ptt and Ptm populations. Significant genetic differentiation (PhiPT = 0.230, P = 0.001) was found among all populations; 77 % of genetic variation occurred within populations and 23 % between populations. Lower, but still significant genetic differentiation (PhiPT = 0.038, P = 0.001) was detected in Ptt, with 96 % of genetic variation occurring within populations. No significant genetic differentiation (PhiPT = 0.010, P = 0.177) was observed among Ptm populations. Isolates clustered in two distinct groups conforming to Ptt or Ptm, with no intermediate cluster. The high number of haplotypes observed, combined with an equal mating type ratio for both forms of the fungus, suggests that P. teres goes through regular cycles of sexual recombination in western Canada. 相似文献
18.
Ahmed A. Kheder Yasunori Akagi Hajime Akamatsu Konomi Yanaga Nitaro Maekawa Hiroshi Otani Takashi Tsuge Motoichiro Kodama 《Journal of General Plant Pathology》2012,78(1):30-38
The tomato pathotype of Alternaria alternata (A. arborescens) produces the dark brown to black pigment melanin, which accumulates in the cell walls of hyphae and conidia. Melanin has
been implicated as a pathogenicity factor in some phytopathogenic fungi. Here, two genes of the tomato pathotype for melanin
biosynthesis, ALM1 and BRM2-1, which encode a polyketide synthetase and a 1,3,8-trihydroxynaphthalene (THN) reductase, respectively, have been cloned and
disrupted in the pathogen. The gene-disrupted mutants, alm1 and brm2-1, had albino and brown phenotypes, respectively. The wild-type and the mutants caused the same necrotic lesions on the leaves
after inoculation with spores. These results suggest that melanin is unlikely to play a direct role in pathogenicity in the
tomato pathotype A. alternata. Scanning electron microscopy revealed that the conidia of both mutants have much smoother surfaces in comparison to the
wild-type. The conidia of those mutants were more sensitive to UV light than those of the wild-type, demonstrating that melanin
confers UV tolerance. 相似文献
19.
This work investigated the ability of the gregarious larval endoparasitoid Cotesia glomerata L. (Hymenoptera: Braconidae) to adjust the progeny sex ratio and clutch size with repeated oviposition experience and the
effect of a honey-based diet on the clutch size. In the field-collected clusters many clusters were female-biased but some
clusters (3.8%) produced only male wasps, suggesting that there is a low percentage of unmated females in the field. Superparasitism
was common in the field, and females were believed to increase progeny sex ratio when attacking previously parasitized hosts.
In the laboratory, the number of eggs laid in a day tended to decrease with increasing female age. For females that were offered
two hosts per day and for those offered three hosts per day, this value became nearly the same at 9 days after the start of
oviposition. Old females which attacked many hosts tended to lay fewer eggs in a day than young ones. However, the degree
of this tendency was not the same for all the parasitoid females of all three groups because sperm remained viable throughout
a female’s lifetime. The amount of sperm used in a single oviposition bout seemed fixed and was not dependent on the number
of eggs laid. Over the 2 days of the clutch size response experiment, the number of hosts a female attacked per day was not
affected by the presence or absence of honey. 相似文献
20.
Guillermo A. Galván Carole F. S. Koning-Boucoiran Wim J. M. Koopman Karin Burger-Meijer Pablo H. González Cees Waalwijk Chris Kik Olga E. Scholten 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(4):499-512
The aim of this research was to study levels of resistance to Fusarium basal rot in onion cultivars and related Allium species, by using genetically different Fusarium isolates. In order to select genetically different isolates for disease testing, a collection of 61 Fusarium isolates, 43 of them from onion (Allium cepa), was analysed using amplified fragment length polymorphism (AFLP) markers. Onion isolates were collected in The Netherlands
(15 isolates) and Uruguay (9 isolates), and received from other countries and fungal collections (19 isolates). From these
isolates, 29 were identified as F. oxysporum, 10 as F. proliferatum, whereas the remaining four isolates belonged to F. avenaceum and F. culmorum. The taxonomic status of the species was confirmed by morphological examination, by DNA sequencing of the elongation factor
1-α gene, and by the use of species-specific primers for Fusarium oxysporum, F. proliferatum, and F. culmorum. Within F. oxysporum, isolates clustered in two clades suggesting different origins of F. oxysporum forms pathogenic to onion. These clades were present in each sampled region. Onion and six related Allium species were screened for resistance to Fusarium basal rot using one F. oxysporum isolate from each clade, and one F. proliferatum isolate. High levels of resistance to each isolate were found in Allium fistulosum and A. schoenoprasum accessions, whereas A. pskemense, A. roylei and A. galanthum showed intermediate levels of resistance. Among five A. cepa cultivars, ‘Rossa Savonese’ was also intermediately resistant. Regarding the current feasibility for introgression, A. fistulosum, A. roylei and A. galanthum were identified as potential sources for the transfer of resistance to Fusarium into onion. 相似文献