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Makoto Kakishima - One of the best experts on this subject based on the ideXlab platform.
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Qualitative morphological characteristics recognized in this study.
2015Co-Authors: Peng Zhao, Qing-hong Wang, Cheng-ming Tian, Makoto KakishimaAbstract:(A) Urediniospores with a smooth apex. (B) Urediniospores without a smooth apex. (C) Uredinia with intermixed paraphyses. (D) Uredinia without intermixed paraphyses. (E) Urediniospores with echinulate type 1 spines. (F) Urediniospores with echinulate type 2 spines. (G) Urediniospores with echinulate type 3 spines. (H) Urediniospores with biozonate germ pores. (I) Urediniospores with scattered germ pores. (J) Paraphyses with evenly thickened membranes. (K) Paraphyses with an apparently thickened apex. (L) Subepidermal teliospores. (M) Subepidermal or subcuticular teliospores. (N) Subcuticular teliospores. Bars: A, H, J, K, M, N = 20 mm; B, F, G, I = 10 mm; C = 50 μm; D = 60 μm; E = 5 μm; L = 30 μm.
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Morphological and phylogenetic analyses of Uromyces appendiculatus and U. vignae on legumes in Japan
Mycoscience, 2004Co-Authors: Wen H. Chung, Takao Tsukiboshi, Makoto KakishimaAbstract:Uromyces appendiculatus , inclusive of three varieties, is distinguished from U. vignae primarily by the position of urediniospore germ pores and putative host specificity. However, opinions concerning these morphological and physiological features as taxonomic characters have varied greatly, and distinction of these species has often been confused. To clarify the taxonomy of these two species, morphological features of Urediniospores and teliospores of 225 rust fungus specimens on species of Phaseolus , Vigna , Apios , Lablab , and Dunbaria were examined by light microscopy and scanning electron microscopy. Forty-five specimens were subjected to molecular phylogenetic analyses. As a result, the position of germ pores in Urediniospores and the teliospore-wall thickness were considered as good characters to separate three morphological groups. In molecular analyses, the specimens fell into two and three clades based on the nucleotide sequence at D1/D2 domain of LSU rDNA and ITS regions, respectively. One of the D1/D2 clades corresponded to one morphological group whereas another D1/D2 clade included two other morphological groups. In contrast, each of the three ITS clades corresponded to a separate morphological group. Neither morphological groups nor molecular clades were host limited. It is suggested that the three morphological groups that corresponded to three distinct ITS clades constitute distinct species.
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Phylogenetic analyses of Uromyces viciae-fabae and its varieties on Vicia, Lathyrus, and Pisum in Japan
Mycoscience, 2004Co-Authors: Wen H. Chung, Yoshitaka Ono, Takao Tsukiboshi, Makoto KakishimaAbstract:A pea rust fungus, Uromyces viciae - fabae , has been classified into two varieties, var. viciae - fabae and var. orobi , based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of Urediniospores and teliospores of 94 rust specimens from Vicia , Lathyrus , and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia , Lathyrus , and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae - fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum . These results suggest that U. viciae - fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.
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Morphological analyses of Urediniospores and teliospores in sevenPhragmidium species parasitic on ornamental roses
Mycoscience, 2001Co-Authors: Dono Wahyuno, Makoto KakishimaAbstract:Ornamental roses worldwide harbor 10 Phragmidium species. Among these P. americanum, P. fusiforme, P. montivagum, P. mucronatum, P. rosae-pimpinellifoliae, P. rosae-rugosae and P. tuberculatum are frequently reported; however, these species are morphologically similar and difficult to distinguish. For better circumscription and correct identification of the species, this study examined morphological features in Urediniospores and teliospores of the seven Phragmidium species collected on ornamental rose cultivars and wild species. The results indicated that some host-specific groups could be well circumscribed by the morphological properties of Urediniospores and teliospores. However, without the precise identification of hosts, these morphological properties were not effective key characters for the identification of the species.
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Aecidium dispori is the aecial anamorph of Puccinia albispora , sp. nov. (Uredinales)
Mycoscience, 2001Co-Authors: Makoto Kakishima, Kaori IshimiyaAbstract:Aecidium dispori forms spermogonium and aecium onDisporum sessile andD. smilacinum, which are distributed in East Asia. TheAecidium species is found to be an aecial anamorph of aPuccinia fungus, with its uredinial-telial stage being formed onCarex conica, C. dolichostachya subsp.multifolia, C. pisiformis subsp.alterniflora andC. rugata. Urediniospores of this fungus are large, colorless, thick-walled with 4–5 equatorial germ pores. The morphological characteristics of Urediniospores and the spermogonial-aecial host do not fit to any set of circumscribing characters of previously described species. We consider the fungus to be a new species and propose a new name,Puccinia albispora, for the fungus.
James W. Buck - One of the best experts on this subject based on the ideXlab platform.
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Detection of Puccinia pelargonii-zonalis-infected Geranium Tissues and Urediniospores
Journal of Phytopathology, 2013Co-Authors: Erika A. Scocco, Steven N Jeffers, Ronald R. Walcott, James W. BuckAbstract:The occurrence of geranium rust (caused by Puccinia pelargonii-zonalis) in commercial greenhouses can result in unmarketable plants and significant economic losses. Currently, detection of geranium rust relies solely on scouting for symptoms and signs of the disease. The purpose of this research was to develop a rapid detection assay for P. pelargonii-zonalis-infected tissues or Urediniospores on greenhouse-grown geraniums. Two oligonucleotide primers were designed based on internal transcribed spacer sequence data from three isolates of P. pelargonii-zonalis. The primers amplified a 131-bp product from genomic DNA from each isolate of P. pelargonii-zonalis but did not amplify a product from genomic DNA from twelve other rust fungi or four other plant pathogenic fungi. A PCR product was amplified consistently from solutions that contained 1 ng or 100 pg/ml of purified P. pelargonii-zonalis DNA in conventional PCR and at 1 pg/ml using real-time PCR. The detection threshold was 102 Urediniospores/ml for real-time PCR and 104 Urediniospores/ml for conventional PCR using Urediniospores collected by vacuum from sporulating lesions. Puccinia pelargonii-zonalis DNA was amplified by real-time PCR from Urediniospores washed from a single inoculated leaf, but recovered Urediniospores were below detection threshold from one inoculated leaf with 5, 10, 25 and 50 non-inoculated leaves. Conventional and real-time PCR did not detect P. pelargonii-zonalis in infected leaf tissues, presumably due to PCR inhibitors in the geranium leaf tissue. The inhibition of both conventional and real-time PCR by geranium tissues suggests that a detection assay focusing on urediniospore recovery and microscopic examination with subsequent species verification by PCR may be the most efficient method for assessing the presence of geranium rust in greenhouses.
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effect of light on in vivo urediniospore germination lesion development and sporulation of puccinia hemerocallidis on daylily and puccinia pelargoniizonalis on geranium
Mycologia, 2011Co-Authors: Weibo Dong, James W. BuckAbstract:The presence of rusts of daylily and geranium caused respectively by Puccinia hemerocalli- dis and P. pelargonii-zonalis can result in reduced value of these ornamental crops. Experiments were conducted to determine the effects of fluorescent light and sunlight on urediniospore germination, germ tube elongation, lesion development and sporulation of the two fungal pathogens on detached leaves and whole plants. Exposure of dry or hydrated Urediniospores of P. hemerocallidis to cool white fluorescent light (600 mmol s 21 m 22 ) or to sunlight (950-1910 mmol s 21 m 22 ) for 2 h or 4 h significantly reduced germination and germ tube elongation on detached daylily leaves. Germination but not germ tube elongation of hydrated Urediniospores of P. pelargonii-zonalis on detached geranium leaves was significantly reduced when exposed to fluorescent light for 2 h or 4 h. A 4 h exposure to either light source significantly reduced lesion development of P. hemerocallidis on detached daylily leaves with fewer lesions developing from hydrated compared to dry Urediniospores. Sunlight exposures of 1 h and 2 h of hydrated and dry Urediniospores respectively signifi- cantly reduced lesion development by either fungus on whole plants. Increasing exposure to fluorescent light negatively affected sporulation of P. hemerocalli- dis and P. pelargonii-zonalis. Complete suppression of sporulation was not observed for either fungus with up to a 24 h exposure to fluorescent light. Light exposure negatively affected disease development by P. hemerocallidis and P. pelargonii-zonalis. Exposure to high light intensities may affect spread of rust diseases on ornamental plants.
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effect of postsymptom application of fungicides on urediniospore production by puccinia triticina on wheat and p hemerocallidis on daylily
Plant Disease, 2011Co-Authors: James W. Buck, K Wise, Weibo DongAbstract:Abstract Greenhouse experiments were conducted to evaluate the effect of post-symptomatic fungicide applications on urediniospore production of leaf rust of wheat, Puccinia triticina, and daylily rust, P. hemerocallidis. Fungicides from five chemical classes were evaluated for their effect on urediniospore production at 24-h intervals post application for 96 h. The quinone outside inhibitor (QoI) fungicide (azoxystrobin) significantly reduced cumulative urediniospore production by P. triticina (40.1 and 11.3% of control) and P. hemerocallidis (37.9 and 35.6% of control) in both trials. The demethylation inhibitor, myclobutanil, significantly reduced urediniospore production by P. hemerocallidis 24 h post treatment in both trials and cumulative production in one trial. Myclobutanil did not affect urediniospore production by P. triticina. Four QoI fungicides significantly reduced urediniospore production by P. triticina at all collection times (24, 48, and 72 h) and cumulative production in both trials. No ...
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toxicity of fungicides to Urediniospores of six rust fungi that occur on ornamental crops
Plant Disease, 2005Co-Authors: Daren S Mueller, Steven N Jeffers, James W. BuckAbstract:ABSTRACT The recent introduction and rapid spread of rust on daylilies, caused by Puccinia hemerocallidis, suggested a need for fungicide treatments that reduce urediniospore viability on plant surfaces. Twelve fungicides in seven chemical classes were evaluated in vitro for toxicity to Urediniospores of rust fungi that occur on daylily (P. hemerocallidis), geranium P. pelargonii-zonalis), iris (P. iridis), oxalis (P. oxalis), mint (P. menthae), and Florida azalea (Pucciniastrum vaccinii). Germination of Urediniospores of all six rust fungi on potato dextrose agar in the absence of fungicides ranged from 54 to 88%. Germination of Urediniospores of all rust species during and after exposure to azoxystrobin, chlorothalonil, copper sulfate pentahydrate, mancozeb, and trifloxystrobin was less than or near 1%. Germination during exposure to fenhexamid, iprodione, myclobutanil, propiconazole, thiophanate-methyl, triadimefon, and triflumizole ranged from 0 to 60% and usually was greater (0 to 75%) after fungicid...
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effects of light temperature and leaf wetness duration on daylily rust
Plant Disease, 2003Co-Authors: Daren S Mueller, James W. BuckAbstract:ABSTRACT Experiments in controlled environments were completed to determine the influence of light intensity, temperature, and leaf wetness duration on daylily rust caused by Puccinia hemerocallidis. As light intensity increased, there was a significant decrease in urediniospore germination (R2 = 0.88 and Y = 96 - 0.6x). Urediniospores germinated in vitro between 7 and 34°C with an optimal temperature of 22 to 24°C. To test the effect of temperature on infection efficiency, plants were inoculated with Urediniospores, incubated under high relative humidity at 4, 10, 22, 30, or 36°C, and then transferred to a greenhouse at 23°C for 15 days. Plants incubated at 22°C had an average of 13 lesions cm leaf-1. Incubation temperatures of 4, 10, 30, or 36°C resulted in less than 1.5 lesions cm leaf-1. Plants were inoculated, incubated at 22°C for 24 h, and then incubated at different temperatures for 15 days to test the effect of temperature on disease development. There were no significant differences in disease d...
Xianming Chen - One of the best experts on this subject based on the ideXlab platform.
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Estimated Puccinia striiformis f. sp. tritici of 5 mg Urediniospores at three storage conditions using the qPCR of DNA (dashed lines) and RNA (solid lines).
2015Co-Authors: Jiaxing Qiao, Xinyu Kong, Yiping Zou, Xianming ChenAbstract:Dashed lines with triangles, squares and circles represent DNA from dead Urediniospores at ambient temperature, fresh Urediniospores at ambient temperature and at -20°C, respectively. Solid lines with triangles, squares and circles represent RNA from dead Urediniospores at ambient temperature, and fresh Urediniospores at ambient temperature and at -20°C, respectively. The experiment was done three times. The vertical bar of each treatment at each time point represents the standard deviation of the three mean values from three experiments; significant treatment differences were based on the pooled residual error in the repeated measurement ANOVA. Treatments with different letters for the 12-days means were significantly different at P = 0.05. There were no significant differences among the treatments on 0, 4 and 8 days at P = 0.05.
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wheat stripe yellow rust caused by puccinia striiformis f sp tritici
Molecular Plant Pathology, 2014Co-Authors: Wanquan Chen, Xianming Chen, C R Wellings, Zhengsheng KangAbstract:SUMMARY Stripe (yellow) rust,caused by Puccinia striiformis f.sp.tritici (Pst), is a serious disease of wheat occurring in most wheat areas with cool and moist weather conditions during the growing season.The basidiomycete fungus is an obligate biotrophic parasite that is difficult to culture on artificial media. Pst is a macrocyclic, heteroecious fungus that requires both primary (wheat or grasses) and alternate (Berberis or Mahonia spp.) host plants to complete its life cycle. Urediniospores have the capacity for wind dispersal over long distances, which may, under high inoculum pressure, extend to thousands of kilometres from the initial infection sites. Stripe rust, which is considered to be the current major rust disease affecting winter cereal production across the world, has been studied intensively for over a century. This review summarizes the current knowledge of the Pst‐wheat pathosystem, with emphasis on the life cycle, uredinial infection process, population biology of the pathogen, genes for stripe rust resistance in wheat and molecular perspectives of wheat‐Pst interactions. Taxonomy: The stripe rust pathogen, Puccinia striiformis Westend. (Ps), is classified in kingdom Fungi, phylum Basidiomycota, class Urediniomycetes, order Uredinales, family Pucciniaceae, genus Puccinia. Ps is separated below the species level by host specialization on various grass genera,comprising up to nine formae speciales, of which P. striiformis f. sp. tritici Erikss. (Pst) causes stripe (or yellow) rust on wheat. Host range: Uredinial/telial hosts: Pst mainly infects common wheat (Triticum aestivum L.), durum wheat (T. turgidum var. durum L.), cultivated emmer wheat (T. dicoccum Schrank), wild emmer wheat (T. dicoccoidesKorn) and triticale (Triticosecale).Pst can infect certain cultivated barleys (Hordeum vulgare L.) and rye (Secale cereale L.),but generally does not cause severe epidemics. In addition,Pst may infect naturalized and improved pasture grass species, such as Elymus canadensis L., Leymus secalinus Hochst, Agropyron spp. Garetn, Hordeum spp. L., Phalaris spp. L and Bromus unioloides Kunth. Pycnial/aecial (alternative) hosts: Barberry (Berberis chinensis, B. koreana, B. holstii, B. vulgaris, B. shensiana, B. potaninii, B. dolichobotrys, B. heteropoda, etc.) and Oregon grape (Mahonia aquifolium). Disease symptoms: Stripe rust appears as a mass of yellow to orange Urediniospores erupting from pustules arranged in long, narrow stripes on leaves (usually between veins), leaf sheaths, glumes and awns on susceptible plants. Resistant wheat cultivars are characterized by various infection types from no visual symptoms to small hypersensitive flecks to uredinia surrounded by chlorosis or necrosis with restricted urediniospore production. On seedlings, uredinia produced by the infection of a single urediniospore are not confined by leaf veins, but progressively emerge from the infection site in all directions, potentially covering the entire leaf surface. Individual uredinial pustules are oblong, 0.4‐0.7 mm in length and 0.1 mm in width. Urediniospores are broadly ellipsoidal to broadly obovoid, (16‐ )18‐30(‐32) × (15‐)17‐27(‐28) μm, with a mean of 24.5 × 21.6 μm, yellow to orange in colour, echinulate, and with 6‐18 scattered germ pores. Urediniospores can germinate rapidly when free moisture (rain or dew) occurs on leaf surfaces and when the temperatures range is between 7 and 12 °C. At higher temperatures or during the later growing stages of the host,black telia are often produced, which are pulvinate to oblong, 0.2‐0.7 mm in length and 0.1 mm in width. The teliospores are predominantly two-celled, dark brown with thick walls, mostly oblong-clavate, (24‐)31‐56(‐65) × (11‐)14‐25(‐29) μm in length and width,and rounded or flattened at the apex.
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generation and analysis of expression sequence tags from haustoria of the wheat stripe rust fungus puccinia striiformis f sp tritici
BMC Genomics, 2009Co-Authors: Xianming Chen, Zhensheng Kang, Xiaojie Wang, Scot H. HulbertAbstract:Background Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat (Triticum aestivum L.) worldwide. In spite of its agricultural importance, the genomics and genetics of the pathogen are poorly characterized. Pst transcripts from Urediniospores and germinated Urediniospores have been examined previously, but little is known about genes expressed during host infection. Some genes involved in virulence in other rust fungi have been found to be specifically expressed in haustoria. Therefore, the objective of this study was to generate a cDNA library to characterize genes expressed in haustoria of Pst.
Weibo Dong - One of the best experts on this subject based on the ideXlab platform.
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effect of light on in vivo urediniospore germination lesion development and sporulation of puccinia hemerocallidis on daylily and puccinia pelargoniizonalis on geranium
Mycologia, 2011Co-Authors: Weibo Dong, James W. BuckAbstract:The presence of rusts of daylily and geranium caused respectively by Puccinia hemerocalli- dis and P. pelargonii-zonalis can result in reduced value of these ornamental crops. Experiments were conducted to determine the effects of fluorescent light and sunlight on urediniospore germination, germ tube elongation, lesion development and sporulation of the two fungal pathogens on detached leaves and whole plants. Exposure of dry or hydrated Urediniospores of P. hemerocallidis to cool white fluorescent light (600 mmol s 21 m 22 ) or to sunlight (950-1910 mmol s 21 m 22 ) for 2 h or 4 h significantly reduced germination and germ tube elongation on detached daylily leaves. Germination but not germ tube elongation of hydrated Urediniospores of P. pelargonii-zonalis on detached geranium leaves was significantly reduced when exposed to fluorescent light for 2 h or 4 h. A 4 h exposure to either light source significantly reduced lesion development of P. hemerocallidis on detached daylily leaves with fewer lesions developing from hydrated compared to dry Urediniospores. Sunlight exposures of 1 h and 2 h of hydrated and dry Urediniospores respectively signifi- cantly reduced lesion development by either fungus on whole plants. Increasing exposure to fluorescent light negatively affected sporulation of P. hemerocalli- dis and P. pelargonii-zonalis. Complete suppression of sporulation was not observed for either fungus with up to a 24 h exposure to fluorescent light. Light exposure negatively affected disease development by P. hemerocallidis and P. pelargonii-zonalis. Exposure to high light intensities may affect spread of rust diseases on ornamental plants.
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effect of postsymptom application of fungicides on urediniospore production by puccinia triticina on wheat and p hemerocallidis on daylily
Plant Disease, 2011Co-Authors: James W. Buck, K Wise, Weibo DongAbstract:Abstract Greenhouse experiments were conducted to evaluate the effect of post-symptomatic fungicide applications on urediniospore production of leaf rust of wheat, Puccinia triticina, and daylily rust, P. hemerocallidis. Fungicides from five chemical classes were evaluated for their effect on urediniospore production at 24-h intervals post application for 96 h. The quinone outside inhibitor (QoI) fungicide (azoxystrobin) significantly reduced cumulative urediniospore production by P. triticina (40.1 and 11.3% of control) and P. hemerocallidis (37.9 and 35.6% of control) in both trials. The demethylation inhibitor, myclobutanil, significantly reduced urediniospore production by P. hemerocallidis 24 h post treatment in both trials and cumulative production in one trial. Myclobutanil did not affect urediniospore production by P. triticina. Four QoI fungicides significantly reduced urediniospore production by P. triticina at all collection times (24, 48, and 72 h) and cumulative production in both trials. No ...
Zhensheng Kang - One of the best experts on this subject based on the ideXlab platform.
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Basidiospores of Puccinia striiformis f. sp. tritici succeed to infect barberry, while Urediniospores are blocked by non-host resistance.
Protoplasma, 2017Co-Authors: Min Jiao, Zhensheng Kang, Chenglong Tan, Long Wang, Jia Guo, Hongchang Zhang, Jun GuoAbstract:Stripe rust (Yellow rust) caused by Puccinia striiformis f. sp. tritici (Pst) is a major disease of wheat worldwide. The use of resistant cultivars to control Pst has been very effective, low-cost, and ecologically sound. However, virulence patterns of Pst can quickly change, which may render resistant cultivars susceptible. The discovery of infection of Berberis spp. by basidiospores of Pst in 2010 raised important concerns about the evolution of new virulent races of the pathogen. Little is known about the infection process of Berberis spp. by basidiospores of Pst and the interaction between Berberis spp. and asexual Urediniospores. In this study, the interaction between Pst Urediniospores and Berberis spp. was investigated at histological and cytological levels. Our results indicate that Berberis spp. expresses a continuum of layered defenses comprised of structural and chemical changes in the cell wall as well as post-haustorial hypersensitive responses to urediniospore infection. Our study also re-examines in detail the infection process of Pst basidiospores on Berberis spp. and provides useful information for further research on the molecular mechanisms governing the interaction between Berberis spp. and Pst.
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Isocitrate lyase is required for urediniospore germination of Puccinia striiformis f. sp. tritici
Molecular biology reports, 2014Co-Authors: Jie Liu, Qiuling Wang, Qing Chang, Lina Han, Guoliang Pei, Yue-qing Xue, Lu-meng Jia, Kun Zhang, Yuan-yuan Duan, Zhensheng KangAbstract:The PstICL1 gene, which encodes isocitrate lyase, a key enzyme in the glyoxylate cycle, was cloned and characterized in the biotrophic wheat pathogen Puccinia striiformis f. sp. tritici (Pst). Expression analyses of PstICL1 exhibited high levels of transcripts in ungerminated Urediniospores, which showed low isocitrate lyase enzyme activity. In planta, PstICL1 expression was continuously down-regulated upon germination. During the later stages of the infection of wheat, the level of PstICL1 expression was extremely low. The function of PstICL1 was identified via mutant complementation. The expression of PstICL1 in Saccharomyces cerevisiae can complement the defects of the △ICL mutant. Using 3-nitropropionate, we observed that inactivation of isocitrate lyase greatly reduced the germination rate of Urediniospores, indicating that PstICL1 plays a key role during Pst germination. Furthermore, analysis of lipid bodies revealed that lipid components continuously enter the germ tube from the urediniospore cell during germ tube elongation. Moreover, during this period, the lipid contents continuously decreased, and the total carbohydrates markedly increased, demonstrating that the lipids are being converted into carbohydrates. These results suggest that PstICL1 is required for Pst germination.
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generation and analysis of expression sequence tags from haustoria of the wheat stripe rust fungus puccinia striiformis f sp tritici
BMC Genomics, 2009Co-Authors: Xianming Chen, Zhensheng Kang, Xiaojie Wang, Scot H. HulbertAbstract:Background Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat (Triticum aestivum L.) worldwide. In spite of its agricultural importance, the genomics and genetics of the pathogen are poorly characterized. Pst transcripts from Urediniospores and germinated Urediniospores have been examined previously, but little is known about genes expressed during host infection. Some genes involved in virulence in other rust fungi have been found to be specifically expressed in haustoria. Therefore, the objective of this study was to generate a cDNA library to characterize genes expressed in haustoria of Pst.
