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1.
Species in the fungal family Botryosphaeriaceae are latent pathogens on woody trees. These fungi often have a wide host range, which can include native and introduced hosts in an area. Multi-locus DNA sequence identification on a recent collection of Botryosphaeriaceae from Eucalyptus grandis and Syzygium cordatum trees in South Africa revealed cross-infectivity of several species, novel host associations and new country reports. Neofusicoccum eucalyptorum, Neofusicoccum kwambonambiense, Neofusicoccum parvum, Neofusicoccum australe and Lasiodiplodia pseudotheobromae were identified from both tree species, with L. pseudotheobromae and N. eucalyptorum isolated for the first time from S. cordatum, similar to N. kwambonambiense from Eucalyptus. This also represents the first report of L. pseudotheobromae from South Africa. Botryosphaeriaceae species on Eucalyptus species and S. cordatum are fairly well known from South Africa. However, this study revealed new associations, indicating that conclusions should not be generalized and that more intensive sampling from different areas and over time is likely to reveal distinct species and host association patterns.  相似文献   

2.
Botryosphaeriaceae species have a wide host range and a worldwide distribution. These fungal species can colonize several plant organs, such as the trunk, leaves and fruit. Some Botryosphaeriaceae species cause important diseases on persimmon, avocado and guava fruit. However, there is a lack of information regarding the mechanisms of penetration by Botryosphaeriaceae species on these tropical and subtropical fruits. This study aimed to better understand the mechanisms involved in fungal penetration, host specificity and aggressiveness of Botryosphaeria dothidea, Lasiodiplodia pseudotheobromae and Neofusicoccum parvum on avocado (Persea americana), guava (Psidium guajava) and persimmon (Diospyros kaki) fruit. Scanning electron microscopy (SEM) image analysis showed that in avocado fruit, the three studied Botryosphaeriaceae species penetrated through lenticels. In guava fruit, penetration through stomata was verified for Botryosphaeria dothidea and Neofusicoccum parvum. In persimmon fruit, an appressoria-like structure was observed for B. dothidea, which suggests direct penetration. Disease incidence in wounded fruit was 24% higher than in non-wounded fruit. Lpseudotheobromae and Nparvum showed differences in aggressiveness in guava fruit. The longest incubation period was observed for Nparvum inoculated on guava, with an average of 4.5 days, and the shortest incubation period was verified for Bdothidea inoculated on avocado, with an average of 2.8 days. The area under the disease progress curve (AUDPC) did not differ between Botryosphaeriaceae species on avocado, whereas on guava and persimmon fruit, the AUDPC was lower for B. dothidea. The information regarding penetration mechanisms and aggressiveness is important to improve postharvest disease control strategies.  相似文献   

3.
《Fungal biology》2022,126(5):342-355
Stem blight is a major disease of blueberry caused by Botryosphaeriaceae fungi. Chemical and cultural management options are limited, putting emphasis on breeding efforts to identify sources of resistance. The efficacy and durability of host resistance could be impacted by the species composition of the pathogen population in a region and by the isolates employed in the screenings used to identify the resistance. Samples (365) were collected from southern highbush (SHB) and rabbiteye blueberry (REB) cultivars from 28 sites in the southeastern US (AL, FL, GA, NC, and SC). Colony morphology identified 86% of the isolates as Botryosphaeriaceae. Conidia morphology and Maximum Likelihood analysis of the Internal Transcribed Spacer rDNA regions (ITS), translation elongation factor one alpha (tef1-α), and β-tubulin were used to identify isolates at genera or species level. A PCR-restriction fragment length polymorphism (PCR-RFLP) test was used to identify isolates to genus. Neofusicoccum and Lasiodiplodia were the predominant genera. N. kwambonambiense, N. ribis, L. theobromae and L. pseudotheobromae were the most common species isolated. Phylogenies conducted with a limited number of isolates indicated non-clonal and potentially diverse populations occur on blueberry that warrant additional study. Botryosphaeria corticis, B. dothidea, and Diplodia seriata were isolated infrequently.  相似文献   

4.
Damm U  Crous PW  Fourie PH 《Mycologia》2007,99(5):664-680
Botryosphaeriaceae are common dieback and canker pathogens of woody host plants, including stone fruit trees. In the present study the diversity of members of the Botryosphaeriaceae isolated from symptomatic wood of Prunus species (plum, peach, nectarine and apricot) was determined in stone fruit-growing areas in South Africa. Morphological and cultural characteristics as well as DNA sequence data (5.8S rDNA, ITS-1, ITS-2 and EF-1a) were used to identify known members and describe novel members of Botryosphaeriaceae. From the total number of wood samples collected (258) 67 isolates of Botryosphaeriaceae were obtained, from which eight species were identified. All species were associated with wood necrosis. Diplodia seriata (= "Botryosphaeria" obtusa) was dominant, and present on all four Prunus species sampled, followed by Neofusicoccum vitifusiforme and N. australe. First reports from Prunus spp. include N. vitifusiforme, Dothiorella viticola and Diplodia pinea. This is also the first report of D. mutila from South Africa. Two species are newly described, namely Lasiodiplodia plurivora sp. nov. from P. salicina and Diplodia africana sp. nov. from P. persica. All species, except Dothiorella viticola, caused lesions on green nectarine and/or plum shoots in a detached shoot pathogenicity assay.  相似文献   

5.
Grapevine trunk diseases (Eutypa dieback, esca and Botryosphaeria dieback) are caused by a complex of xylem-inhabiting fungi, which severely reduce yields in vineyards. Botryosphaeria dieback is associated with Botryosphaeriaceae. In order to develop effective strategies against Botryosphaeria dieback, we investigated the molecular basis of grapevine interactions with a virulent species, Neofusicoccum parvum, and a weak pathogen, Diplodia seriata. We investigated defenses induced by purified secreted fungal proteins within suspension cells of Vitis (Vitis rupestris and Vitis vinifera cv. Gewurztraminer) with putative different susceptibility to Botryosphaeria dieback. Our results show that Vitis cells are able to detect secreted proteins produced by Botryosphaeriaceae, resulting in a rapid alkalinization of the extracellular medium and the production of reactive oxygen species. Concerning early defense responses, N. parvum proteins induced a more intense response compared to D. seriata. Early and late defense responses, i.e., extracellular medium alkalinization, cell death, and expression of PR defense genes were stronger in V. rupestris compared to V. vinifera, except for stilbene production. Secreted Botryosphaeriaceae proteins triggered a high accumulation of δ-viniferin in V. vinifera suspension cells. Artificial inoculation assays on detached canes with N. parvum and D. seriata showed that the development of necrosis is reduced in V. rupestris compared to V. vinifera cv. Gewurztraminer. This may be related to a more efficient induction of defense responses in V. rupestris, although not sufficient to completely inhibit fungal colonization. Overall, our work shows a specific signature of defense responses depending on the grapevine genotype and the fungal species.  相似文献   

6.
Three anamorph genera of the Botryosphaeriaceae namely Diplodia, Lasiodiplodia and Dothiorella have typically dark, ovoid conidia with thick walls, and are consequently difficult to distinguish from each other. These genera are well-known pathogens of especially pine species. We generated a multiple gene genealogy to resolve the phylogenetic relationships of Botryosphaeriaceae with dark conidial anamorphs, and mapped host associations based on this phylogeny. The multiple gene genealogy separated Diplodia, Lasiodiplodia and Dothiorella and it revealed trends in the patterns of host association. The data set was expanded to include more lineages of the Botryosphaeriaceae, and included all isolates from different host species for which ITS sequence data are available. Results indicate that Diplodia species occur mainly on gymnosperms, with a few species on both gymnosperms and angiosperms. Lasiodiplodia species occur equally on both gymnosperms and angiosperms, Dothiorella species are restricted to angiosperms and Neofusicoccum species occur mainly on angiosperms with rare reports on Southern Hemisphere gymnosperms. Botryosphaeria species with Fusicoccum anamorphs occur mostly on angiosperms with rare reports on gymnosperms. Ancestral state reconstruction suggests that a putative ancestor of the Botryosphaeriaceae most likely evolved on the angiosperms. Another interesting observation was that both host generalist and specialist species were observed in all the lineages of the Botryosphaeriaceae, with little evidence of host associated co-evolution.  相似文献   

7.
《Journal of bryology》2013,35(4):665-673
Abstract

Lejeunea obtusata Gott. is described and recorded from Madagascar, Mauritius, Tanzania, Ghana, Sierra Leone and probably Uganda. L. cantabrigiensis E.W. Jones sp. nov. is described from Cameroon Mountain. L. obtusistipula (Steph.) E.W. Jones, comb. nov. (Cheilolejeunea obtusistipula Steph.) is described from Sierra Leone. Taxonomic notes on allied species, including L. confusa E.W. Jones, are included.  相似文献   

8.
The genus Ptilophora currently includes 16 species occurring mostly in subtidal habitats of the Indo‐Pacific Ocean, but its global diversity and biogeography are poorly understood. We analyzed mitochondrial cox1, plastid rbcL and plastid psbA sequences from specimens collected in southern Madagascar during the 2010 Atimo Vatae expedition and studied their morphologies. Both morphological and molecular data sets demonstrated the presence of five species in southern Madagascar: Ptilophora hildebrandtii, P. pterocladioides, and three new species described here, P. aureolusa, P. malagasya, and P. spongiophila. Ptilophora aureolusa is distinguished by its compound pinnae with uniformly spaced pinnules. Ptilophora malagasya has an indistinct midrib and irregularly spaced pinnules. Ptilophora spongiophila, heavily coated with sponges, has cylindrical to flattened main axes, lateral and surface proliferations, and spatulate tetrasporangial sori. The species of Ptilophora found in Madagascar are endemic, except P. hildebrandtii, which also occurs in eastern Africa. Ptilophora comprises four phylogenetic groups that map to eastern Australia, Japan, western Australia/Southeast Asia/Madagascar/eastern Africa, and Madagascar/eastern Africa/Aegean Sea. Biogeographical analysis revealed that the ancestor of Ptilophora originated in Australia, but most of the species radiated from Madagascar.  相似文献   

9.
China is the largest walnut producer in the world, and walnut trees, especially English walnut, are widely distributed in the country. Species of Botryosphaeriaceae include important plant pathogens that can cause diseases on many tree crops including English walnut. Recently, disease symptoms caused by Botryosphaeriaceae were observed on English walnut branches or kernels from Beijing, Henan and Sichuan provinces in China. Based on morphological characteristics and phylogenetic analyses of the ITS rDNA sequences and translation elongation factor 1‐alpha (TEF‐1α) gene regions, Botryosphaeria dothidea and Lasiodiplodia pseudotheobromae were identified. Pathogenicity tests showed that both species are virulent to English walnut. To our knowledge, this is the first report of L. pseudotheobromae infecting English walnut in the world.  相似文献   

10.
《Fungal biology》2020,124(6):571-578
Botryosphaeriaceae fungi are phytopathogens and human opportunists. The influence of temperature on the phytotoxicity and cytotoxicity of culture filtrates of five Botryosphaeriaceae species was investigated. All culture filtrates of fungi grown at 25 °C were phytotoxic: symptoms were evaluated based on visual inspection of necrosis areas and on the maximum quantum yield of photosystem II, Fv/Fm. Diplodia corticola and Neofusicoccum kwambonambiense were the most phytotoxic, followed by Neofusicoccum parvum CAA704 and Botryosphaeria dothidea. Phytotoxicity dramatically decreased when strains were grown at 37 °C, except for B. dothidea. All strains, except N. parvum CAA366 and Neofusicoccum eucalyptorum, grown either at 25 °C or 37 °C, were toxic to mammalian cells; at 25 °C and at 37°C, D. corticola and B. dothidea were the most cytotoxic, respectively. Although the toxicity of B. dothidea to both cell lines and of N. kwambonambiense to Vero cells increased with temperature, the opposite was found for the other species tested. Our results suggest that temperature modulates the expression of toxic compounds that, in a scenario of a global increase of temperature, may contribute to new plant infections but also human infections, especially in the case of B. dothidea.  相似文献   

11.
The Botryosphaeriaceae are common and diverse members of fungal communities infecting woody plants. They are also increasingly being used as model organisms to understand patterns in the global movement of latent pathogens. The aim of this study was to consider the species richness of the Botryosphaeriaceae associated with the native Acacia (Vachellia) karroo across South Africa, and the variation of species at specific local sites over time. The diversity of these fungi associated with different tissues of this host plant was also considered. These questions were addressed by sampling healthy A. karroo from 23 sites in South Africa and by more intensive hierarchical sampling conducted at 40 sites in one area over 3 yr. In total, 13 species of the Botryosphaeriaceae were identified, including seven that were isolated only from the more intensively sampled area. There was a clear geographical influence, with some species occurring only in some parts of the country. Significant variation in the species richness over time for the intensively sampled area was found and there was no evidence of tissue specificity for this group of fungi in leaves, branches and branchlets. Results of pathogenicity trials showed highly variable lesion sizes for the isolated species in comparison to the control, with Sphaeropsis variabilis, Lasiodiplodia theobromae and Neofusicoccum australe being the most pathogenic. The overall results revealed a rich diversity of Botryosphaeriaceae on this native host, which varied significantly both geographically and on individual trees, even in the absence of obvious disease.  相似文献   

12.
An understanding of the patterns of variation within and among populations of tropical trees is essential for devising optimum genetic management strategies for their conservation and sustainable utilization. Here, random amplified polymorphic DNA (RAPD) analysis was used to partition variation within and among 10 populations of the endangered Afromontane medicinal tree, Prunus africana, sampled from five countries across the geographical range of the species (Cameroon, Ethiopia, Kenya, Madagascar and Uganda). Analysis of molecular variance ( AMOVA ) employed 48 RAPD markers and revealed most variation among countries (66%, P < 0.001). However, variation among individuals within populations and among populations within Cameroon and Madagascar was also highly significant. Analysis of population product frequency data indicated Ugandan material to be more similar to populations from Cameroon than populations from Kenya and Ethiopia, while Malagash populations were most distinct. The implications of these findings for determining appropriate approaches for conservation of the species, particularly in Cameroon and Madagascar, are discussed.  相似文献   

13.
《Fungal biology》2023,127(5):1010-1031
The Botryosphaeriaceae family comprises numerous fungal pathogens capable of causing economically meaningful diseases in a wide range of crops. Many of its members can live as endophytes and turn into aggressive pathogens following the onset of environmental stress events. Their ability to cause disease may rely on the production of a broad set of effectors, such as cell wall-degrading enzymes, secondary metabolites, and peptidases. Here, we conducted comparative analyses of 41 genomes representing six Botryosphaeriaceae genera to provide insights into the genetic features linked to pathogenicity and virulence. We show that these Botryosphaeriaceae genomes possess a large diversity of carbohydrate-active enzymes (CAZymes; 128 families) and peptidases (45 families). Botryosphaeria, Neofusicoccum, and Lasiodiplodia presented the highest number of genes encoding CAZymes involved in the degradation of the plant cell wall components. The genus Botryosphaeria also exhibited the highest abundance of secreted CAZymes and peptidases. Generally, the secondary metabolites gene cluster profile was consistent in the Botryosphaeriaceae family, except for Diplodia and Neoscytalidium. At the strain level, Neofusicoccum parvum NpBt67 stood out among all the Botryosphaeriaceae genomes, presenting a higher number of secretome constituents. In contrast, the Diplodia strains showed the lowest richness of the pathogenicity- and virulence-related genes, which may correlate with their low virulence reported in previous studies. Overall, these results contribute to a better understanding of the mechanisms underlying pathogenicity and virulence in remarkable Botryosphaeriaceae species. Our results also support that Botryosphaeriaceae species could be used as an interesting biotechnological tool for lignocellulose fractionation and bioeconomy.  相似文献   

14.
Mehl JW  Slippers B  Roux J  Wingfield MJ 《Mycologia》2011,103(3):534-553
There have been several recent reports of Pterocarpus angolensis (kiaat) trees dying in South Africa, Zambia and Zimbabwe, where this tree is used in traditional medicine and is a valuable source of timber for woodcarving and furniture. A survey of material from diseased P. angolensis trees in South Africa yielded isolates of the Botryosphaeriaceae, an important fungal family known to cause a number of tree diseases. The aim of this study was to identify these Botryosphaeriaceae and to determine their pathogenicity to P. angolensis with branch inoculations. Seven species of the Botryosphaeriaceae were identified based on a combination of morphological characteristics and sequences from the ITS and EF-1α gene regions. Four of these represent undescribed taxa for which the names Pseudofusicoccum violaceum, P. olivaceum, Diplodia alatafructa and Fusicoccum atrovirens are provided. The remaining three species collected include Lasiodiplodia theobromae, L. pseudotheobromae and L. crassispora. Inoculation trials on tree branches showed that L. pseudotheobromae and one isolate of D. alatafructa differed significantly from control inoculations. The high levels of virulence and common occurrence of L. pseudotheobromae suggest that this species could play a role in tree dieback and death.  相似文献   

15.
Aim We provide the first in‐depth study of the Branchiopoda of the rain forests of Cameroon and also of the African continent. Location Surface water environments, Cameroon. Methods Qualitative plankton samples were collected in all types of surface water environments present, ranging from big lakes to water collected in rock crevices or fallen fruit cavities. A tow or hand‐held plankton net of mesh size 100 μm was used, and water volumes filtered were at least several m3 in large water bodies, or half to whole water volume in small water bodies. Results We recorded 61 species (53 first records for the country), based on 700+ samples collected between September 1998 and March 2002. Anomopoda (92%) was the dominant order, followed by Ctenopoda (6.5%) and Cyclestherida (1.5%). Chydoridae (67%) was the most speciose family followed by Macrothricidae (6.5%) and Daphniidae (5%). Alona (11%) was the dominant genus followed by Chydorus (10%) and Pleuroxus (8%). Several species of Chydorinae, especially of the genus Pleuroxus, are shared with continental Eurasia–North America, but are absent from the Mediterranean and desert–steppe–savanna zones of Africa (boreal–tropical disjunction). Daphnia was absent, as in most tropical lowlands. No single species was really abundant, and a majority were rare to very rare, and of restricted occurrence within the rain forest patches. Comparing Africa, South America and Southeast Asia, we found a current total of 196 species for the combined rain forest areas, out of a world total of 500+ species. Systematic trends in richness at three taxonomic levels were the same for all continents: Anomopoda–Ctenopoda–Cyclestherida at ordinal level, Chydoridae–Daphniidae–Macrothricidae–Sididae at family level and Alona–Chydorus–Macrothrix–Diaphanosoma at genus level. Southeast Asia was richest (111 species, 14 endemics) with South America a close second (110 species, 27 endemics). Africa was the most species‐poor (95 species, of which only 5 are endemics). Main conclusions We hypothesize that the post‐Miocene cooling and aridization of the world climate hit the freshwater biota of Africa particularly hard, with more extinction here than elsewhere, and little recolonization. Most extinction occurred in the savanna‐desert belt, and eight disjunct boreal species (four Pleuroxus, Picripleuroxus laevis, Kurzia latissima, Alonella exigua, and Monospilus dispar) survive morphologically unchanged since pre‐Pleistocene times in the Cameroon rain forest. Slow evolution thus appears typical of these cyclic parthenogenetic branchiopods in which sexual recombination occurs only at intervals. Illustrative of the same slow evolution is the fact that the two endemic cladocerans of Cameroon (Nicsmirnovius camerounensis and Bryospilus africanus) belong to tropicopolitan genera of Gondwanan age.  相似文献   

16.
Three different fungi (isolates IVIA QCV‐1, IVIA QCV‐3 and IVIA QCV‐4) were isolated as potential causal agents of postharvest decay losses observed on sweet persimmons (Diospyros kaki L.) cv. ‘Rojo Brillante’ from commercial packinghouses in the Valencia area (Spain). Disease symptoms were irregular brownish and soft lesions mainly located under and surrounding the fruit calyx (stem‐end) that expanded rapidly at room temperature and turned to dark brown or black colour producing apparent and in some cases abundant white to grey mycelium. The identification of Lasiodiplodia theobromae, Neofusicoccum mediterraneum and Neofusicoccum luteum by macroscopic and microscopic morphological observations was confirmed with the amplification and subsequent sequencing of the ribosomal DNA ITS2 region. Representative nucleotide sequences were deposited in GenBank. Pathogenicity of all three isolates was demonstrated by fulfilling Koch's postulates.  相似文献   

17.
《Fungal biology》2021,125(9):718-724
The Botryosphaeriaceae is a family of endophytic fungi, many of which are latent pathogens of woody plants. Although extensively sampled in some parts of the world, little is known regarding their occurrence across different environmental conditions. This study considered the presence of the Botryosphaeriaceae on Syzygium cordatum trees across a latitudinal gradient. We examined the relative importance of different environmental factors on the presence of the Botryosphaeriaceae across this latitudinal gradient. Specifically, Botryosphaeriaceae community composition and species richness were analysed. The optimal growth temperature of the most common Botryosphaeriaceae isolates and its relation to isolate origin was also tested in culture. We identified 14 Botryosphaeriaceae species including seven each of Lasiodiplodia and Neofusicoccum species. The maximum historical temperature emerged as the environmental factor that best predicted the presence of Botryosphaeriaceae species in S. cordatum trees, specifically influencing Botryosphaeriaceae community composition. For all the Botryosphaeriaceae species studied in vitro, temperature strongly influenced mycelial growth and they all had an optimal growth temperature of 25 °C. Contrary to our hypothesis, the optimal growth temperature was not related to isolate origin. These results contribute to understanding the presence of the Botryosphaeriaceae in trees and our ability to detect these latent pathogens.  相似文献   

18.
Species of Lasiodiplodia are important pathogens of a wide variety of plants covering a wide geographical distribution. These fungi can be associated with different symptoms such as stem cankers, shoot blights, fruit rots, dieback and gummosis. Diseases caused by Lasiodiplodia were surveyed on Eucalyptus urophylla × grandis, Polyscias balfouriana and Bougainvillea spectabilis in a nursery in southern China. Based on morphology characteristics and phylogenetic analyses of ITS rDNA sequences and translation elongation factor 1‐alpha (TEF‐1α) gene regions, four species of Lasiodiplodia were identified. Lasiodiplodia theobromae was identified from E. urophylla × grandis, P. balfouriana and B. spectabilis. L. hormozganensis, L. iraniensis and L. pseudotheobromae were identified from B. spectabilis. To our knowledge, with the exception of L. theobromae on E. urophylla × grandis, this study represents the first report of these fungi on the host plants. Pathogenicity tests showed that all Lasiodiplodia spp. obtained in this study are virulent to E. urophylla × grandis and B. spectabilis, and L. theobromae was virulent to P. balfouriana.  相似文献   

19.
Abstract. Species of the tribe Hiletini are rarely represented in collections. Of the twenty known species, only three have been adequately collected. These twenty species are here arrayed in two genera, Hiletus (six species in two spe'cies groups), Eucamaragnathus (fourteen species in five species groups). Hiletus species occur in tropical Africa. Eucamaragnathus species of the alluaudi group occur in tropical and southeastern Africa, those of the suberbiei group are found only in Madagascar, those of the bocandei group are found in tropical western Africa, species of the sumatrensis group occur in southeastern Asia (Burma, Vietnam, Sumatra and Borneo), and those of the batesi group are found in the western Amazon Basin, northeastern Amazon Basin, and along the Paraquay River drainage system. Four new species of Hiletini are described from the following type localities: Hiletus nimba, GUINEA, Nimba Mountains; Eucamaragnathus borneensis, BRUNEI, (BORNEO); E.jaws, BRAZIL, Parana; E.amapa, BRAZIL, Territory of Amapa. Most species of Hiletini live in tropical climates with a mean annual temperature above 21°C and mean annual rainfall above 200 cm (exceptions are noted in text). All species apparently frequent latosolic soils in broadleaf evergreen or deciduous forests or in grassland savannahs with scattered or gallery broadleaf evergreen trees. Records available indicate that pupation occurs during the dry season and that adults emerge with the onset of rains. The structure of the mandibles, other mouthparts, crop and proventriculus suggests that only liquid food is normally taken in, and it is probable that at least some preoral digestion occurs as in other carabids. A suite of newly discovered character states associated with the tarsal claws unites the Hiletini with Cnemacanthini, Elaphrini, Migadopini, Promecognathini, Pseudomor-phini, Scaritini and Siagonini. These stocks together form a sister lineage to the ozaenine-brachinine lineage, all having distinct epimera, brushy non-styliform parameres, long empodial unguitractor plates, but not having conjunct mesocoxae (type I). Hiletini is the sister group of the combined Scaritini-Cnemacanthini-Pseudomorphini stocks. We suggest that the origin of the Hiletini occurred at least as early as the Jurassic Period from an equatorial position near the centre of the combined Africa/South America landmass. By mid-Cretaceous, radiation of taxa occurred across southern Laurasia into the southeastern part of that landmass, but never leaving equatorial climates. Later in the Cretaceous or early Tertiary, when continents began their rapid break-up, hiletines were stranded in tropical parts of South America, Africa/Madagascar, and southeastern Asia where they still occur today.  相似文献   

20.
Botryosphaeriaceae represents an important and diverse family of latent fungal pathogens of woody plants. We address the question of host range of these fungi by sampling leaves and branches of four native South African trees, including Acacia karroo (Fabaceae), Celtis africana (Cannabaceae), Searsia lancea (Anacardiaceae), and Gymnosporia buxifolia (Celastraceae). Two new species of the Botryosphaeriaceae, namely Tiarosporella africana sp. nov. and Aplosporella javeedii sp. nov. were identified, together with five known species, including Neofusicoccum parvum, Neofusicoccum kwambonambiense, Spencermartinsia viticola, Diplodia pseudoseriata, and Botryosphaeria dothidea. Most Botryosphaeriaceae occurred on more than one host. With the exception of S. lancea, which was infected by A. javeedii all the hosts were infected by more than one Botryosphaeriaceae species. Collectively, the results suggest that some intrinsic host factors, possibly combined with local environmental conditions, affect the distribution and co-infectivity of various hosts by the Botryosphaeriaceae. This would counteract the general ability of a species in the Botryosphaeriaceae to infect a broad range of plants. The combination of host and environmental factors might also explain why some Botryosphaeriaceae with apparently broad host ranges, are found on different suites of hosts in different areas of the world.  相似文献   

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