Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular ac...Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular accumulation of reducing equivalents NADH and FADH_(2),requiring a cytosolic shuttling machinery towards mitochondria.Our previous studies identified the mitochondrial D-lactate dehydrogenase MoDld1 as a regulator to channel the metabolite flow in conjunction with redox homeostasis.However,the regulator(s)facilitating the cytosolic redox balance and the importance in propelling nutrient metabolite flow remain unknown.The G-3-P shuttle is a conserved machinery transporting the cytosolic reducing power to mitochondria.In P.oryzae,the mitochondrial G-3-P dehydrogenase Gpd2 was required for cellular NAD^(+)/NADH balance and fungal virulence.In this study,we relocate the mitochondrial G-3-P dehydrogenase Gpd2 to the cytosol for disturbing cytosolic redox status.Our results showed overexpression of cytosolic gpd2^(Δmts)without the mitochondrial targeted signal(MTS)driven by Ribosomal protein 27 promoter(PR27)exerted conflicting regulation of cellular oxidoreductase activities compared to theΔModld1 deletion mutant by RNA-seq and prevented the conidiation and pathogenicity of P.oryzae.Moreover,overexpression of gpd2^(Δmts)caused defects in glycogen and lipid mobilization underlying asexual and infectious structural development associated with decreased cellular NADH production and weakened anti-oxidation activities.RNA-seq and non-targeted metabolic profiling revealed down-regulated transcriptional activities of carbohydrate metabolism and lower abundance of fatty acids and secondary metabolites in RP27:gpd2^(Δmts).Thus,our studies indicate the essential role of cytosolic redox control in nutrient metabolism fueling the asexual and infection-related development in P.oryzae.展开更多
Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzan...Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzania. Studies were conducted to determine the effect of aqueous extracts of Aloe vera, Allium sativum, Annona muricata, Azadirachta indica, Bidens pilosa, Camellia sinensis, Chrysanthemum coccineum, processed Coffee arabica, Datura stramonium, Nicotiana tabacum and Zingiber officinalis for control of rice blast disease (Pyricularia grisea) in-vitro and in-vivo. The results indicate that processed C. arabica at 10% and 25% (v/v) had the highest (81.12%) and (89.40%) inhibitory effect, respectively, against P. grisea. Aqueous extract from N. tabacum at 10% concentration ranked third (80.35%) in inhibiting P. grisea. These were followed by extracts from 25% A. vera (79.45%) and 25% C. coccineum flower (78.83%). The results also indicate that, extracts from A. indica, A. vera, A. sativum, C. arabica, D. stramonium, C. sinensis, Z. officinalis and N. tabacum did not have any phytotoxic effect on seed germination, shoot height, root length, dry weight, seedling growth and seedling vigour index. These plant extracts can thus be used for rice seed treatment to manage rice blast disease.展开更多
Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice ...Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice field located in Selangor State/Malaysia. The obtained strain (UPMZ01) was conducted against Pyricularia oryzea by applying dual culture and culture filtrate technique. The antagonism of strain UPMZ01 in the dual culture was 81.326% inhibition percentage against P. oryzae given the optimum inhibitory percentage 100% at all concentration of secondary metabolites aged 14 days. The isolate (UPMZ01) was identified as Aspergillus niger with accession number (KY698415). The environment factors such as pH and temperature influencing on production of secondary metabolites. The results were shown that pH at level 5.0 and temperature between 21℃?to 29℃?is the optimum condition for A. niger to produce efficient antifungal metabolites which given 100% PIGR against blast pathogen. The secondary metabolites compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen compounds were recognized as major compounds which may have the possibility of possessing antifungal characteristics. Most of identified compounds are Oleic Acid, n-Hexadecanoic acid, Hexose, Glycerol, Stearic acid, Tetradecanoic acid, Dodecanoic acid and 5-Hydrxoymethylfurfural.展开更多
We investigated the possibility to reduce the usage of Blasin^Flowable （BF）, a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbu...We investigated the possibility to reduce the usage of Blasin^Flowable （BF）, a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles （CO2MB）. Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO2MB generated by the decompression-type generator compared to CO2 millibubbles （CO2MMB） and CO2MB generated by the gas-water circulating-type generator. Appressodum formation in the 10 000-fold diluted BF solution containing both CO2MBs was less than that in CO2MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO2MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO2MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO2MB.展开更多
A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Thro...A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Through a systematic screening process involving the use of Pyricularia oryzae mode, 90 bacteria and 31 fungi strains demonstrating positive bioactivities were identified. The rates of active strains of marine bacteria and marine fungi were 6.5% and 4.5%, respectively. The relationships between the active strains and the sampling locations and hosts were studied. For marine bacteria, the three locations showing the highest rotes of active strains were 8.4% in the Zhujiang Estuary, 7.2% at the North Pole and 6.3% in the Bohai Sea. For marine fungi, the highest rates observed were 7.8% at the South Pole, 7.4% in the South China Sea and 6.8% at the Qingdao tideland. An analysis of the host showed that the three highest rates of active strain for marine bacteria were 8.2% for seawater from the Zhujiang Estuary, 8% for alga from the Qingdao tideland and 7.6% for sea mud from the North Pole. For marine fungi, the highest rates observed were 8.3% for Qingdao actiniae, 7.4% for South China Sea poriferan and 4.5% for soil of Qingdao Suaeda salsa. Four fungi and two bacteria samples were selected for further study because of their high bioactivity. They were found to be active towards several pathogenic microorganisms, and demonstrated stable genetic and thermal characteristics and conservation activities.展开更多
In order to clear the composition and distribution of physiological races of Pyricularia oryae in Heilongjiang Province, 299 single spore isolates of P. oryae collected from five rice regions （30 cities, counties or ...In order to clear the composition and distribution of physiological races of Pyricularia oryae in Heilongjiang Province, 299 single spore isolates of P. oryae collected from five rice regions （30 cities, counties or farms） in Heilongiiang Province form 2007 to 2011 were identified by seven differential varieties in Chi- na, and a total of seven groups with 31 physiological races had been identified. The results showed that ZA, ZD and ZB groups were the dominant groups in Hei- longjiang Province, with the occurrence frequencies of 34.8%, 31.1% and 16.1%, respectively. ZD5 was the dominant race with the oeeurrence frequency of 17.1% ; followed by ZA49 and ZD1 , with the occurrence frequencies of 13.7% and 10.7% , respectively. The types and compositions of physiological races of P. oryae varied with rice regions.展开更多
Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya....Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya.Host resistance is the most economical and effective means of controlling the disease as finger millet is grown by resource-poor farmers.This study evaluated a hundred finger millet genotypes for resistance to blast at KALRO(Kenya Agricultural Research and Livestock Organization)Kakamega and Alupe,Kenya for two seasons in 2011/2012 in a lattice square design for two seasons each.Data on blast incidence and severity were measured.Data were analyzed using ANOVA(analysis of variance)and means separated using Duncan multiple range test(DMRT)at p<0.005.The results showed that disease severity was highest in early maturing varieties and lowest in the late maturing varieties.The most resistant genotypes were:GBK000702,GBK000513,GBK029869,GULU-E,GBK000752 and Busibwabo.Pearson correlation analysis between neck severity and physiological maturity was positively significant(r=-0.47).A strong positive correlation between finger severity and neck severity(r=0.87)was observed.These tolerant genotypes could be utilized as donor parents for breeding durable blast resistant varieties.展开更多
Pyricularia oryzae is a fungal pathogen of rice.Few researches had been reported on the analysisof its genome, partly because the genomes can’t beseparated by general agarose gel electrophoresis.We herein report a te...Pyricularia oryzae is a fungal pathogen of rice.Few researches had been reported on the analysisof its genome, partly because the genomes can’t beseparated by general agarose gel electrophoresis.We herein report a technique to separatePyricularia oryzae genomic DNA by pulse-fieldgel electrophoresis(PFGE).The tested blast strain was 2539w.Chromosomal DNAs were directly prepared from展开更多
Five triterpenoid saponins were isolated from the Chinese traditional medicine Eclipta prostrata L.. On the basis of their chemical properties and spectral data, they were identified as eclalbasaponins II(1), I(2), II...Five triterpenoid saponins were isolated from the Chinese traditional medicine Eclipta prostrata L.. On the basis of their chemical properties and spectral data, they were identified as eclalbasaponins II(1), I(2), III(3), 3-O-[b-D-glucopyranosyl(12)-b-D-glucopyranosyl]-16a-ethoxy-olean-12-ene-28-oic acid-28-O-b-D-glu-copyranoside(4) and 3-O-[(2-O-sulfuryl-b-D-glucopyranosyl)(12)-b-D-glucopyranosyl]-echinocystic acid-28-O-b-D-glucopyranoside(5). Compounds 4 and 5 are new compounds and named eclalbasaponins XI and XII, respectively. Compounds 1 and 5 induced morphological deformation of Pyricularia oryzae mycelia.展开更多
基金funded by the National Natural Science Foundation of China(32272513 and 31770156)the Natural Sciences and Engineering Research Council of Canada(Discovery Grant,RGPIN-2016-05356)the Canadian Foundation for Innovation(Discovery Grant,227398-2011)。
文摘Oxidation of self-stored carbohydrates and lipids provides the energy for the rapid morphogenetic transformation during asexual and infection-related development in Pyricularia oryzae,which results in intracellular accumulation of reducing equivalents NADH and FADH_(2),requiring a cytosolic shuttling machinery towards mitochondria.Our previous studies identified the mitochondrial D-lactate dehydrogenase MoDld1 as a regulator to channel the metabolite flow in conjunction with redox homeostasis.However,the regulator(s)facilitating the cytosolic redox balance and the importance in propelling nutrient metabolite flow remain unknown.The G-3-P shuttle is a conserved machinery transporting the cytosolic reducing power to mitochondria.In P.oryzae,the mitochondrial G-3-P dehydrogenase Gpd2 was required for cellular NAD^(+)/NADH balance and fungal virulence.In this study,we relocate the mitochondrial G-3-P dehydrogenase Gpd2 to the cytosol for disturbing cytosolic redox status.Our results showed overexpression of cytosolic gpd2^(Δmts)without the mitochondrial targeted signal(MTS)driven by Ribosomal protein 27 promoter(PR27)exerted conflicting regulation of cellular oxidoreductase activities compared to theΔModld1 deletion mutant by RNA-seq and prevented the conidiation and pathogenicity of P.oryzae.Moreover,overexpression of gpd2^(Δmts)caused defects in glycogen and lipid mobilization underlying asexual and infectious structural development associated with decreased cellular NADH production and weakened anti-oxidation activities.RNA-seq and non-targeted metabolic profiling revealed down-regulated transcriptional activities of carbohydrate metabolism and lower abundance of fatty acids and secondary metabolites in RP27:gpd2^(Δmts).Thus,our studies indicate the essential role of cytosolic redox control in nutrient metabolism fueling the asexual and infection-related development in P.oryzae.
文摘Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzania. Studies were conducted to determine the effect of aqueous extracts of Aloe vera, Allium sativum, Annona muricata, Azadirachta indica, Bidens pilosa, Camellia sinensis, Chrysanthemum coccineum, processed Coffee arabica, Datura stramonium, Nicotiana tabacum and Zingiber officinalis for control of rice blast disease (Pyricularia grisea) in-vitro and in-vivo. The results indicate that processed C. arabica at 10% and 25% (v/v) had the highest (81.12%) and (89.40%) inhibitory effect, respectively, against P. grisea. Aqueous extract from N. tabacum at 10% concentration ranked third (80.35%) in inhibiting P. grisea. These were followed by extracts from 25% A. vera (79.45%) and 25% C. coccineum flower (78.83%). The results also indicate that, extracts from A. indica, A. vera, A. sativum, C. arabica, D. stramonium, C. sinensis, Z. officinalis and N. tabacum did not have any phytotoxic effect on seed germination, shoot height, root length, dry weight, seedling growth and seedling vigour index. These plant extracts can thus be used for rice seed treatment to manage rice blast disease.
文摘Aspergillus spp. has been widely found as useful microorganism in biotechnology. They have a high ability in the production of secondary metabolites. Therefore, isolates of Aspergillus were isolated from healthy rice field located in Selangor State/Malaysia. The obtained strain (UPMZ01) was conducted against Pyricularia oryzea by applying dual culture and culture filtrate technique. The antagonism of strain UPMZ01 in the dual culture was 81.326% inhibition percentage against P. oryzae given the optimum inhibitory percentage 100% at all concentration of secondary metabolites aged 14 days. The isolate (UPMZ01) was identified as Aspergillus niger with accession number (KY698415). The environment factors such as pH and temperature influencing on production of secondary metabolites. The results were shown that pH at level 5.0 and temperature between 21℃?to 29℃?is the optimum condition for A. niger to produce efficient antifungal metabolites which given 100% PIGR against blast pathogen. The secondary metabolites compounds were identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen compounds were recognized as major compounds which may have the possibility of possessing antifungal characteristics. Most of identified compounds are Oleic Acid, n-Hexadecanoic acid, Hexose, Glycerol, Stearic acid, Tetradecanoic acid, Dodecanoic acid and 5-Hydrxoymethylfurfural.
文摘We investigated the possibility to reduce the usage of Blasin^Flowable （BF）, a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles （CO2MB）. Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO2MB generated by the decompression-type generator compared to CO2 millibubbles （CO2MMB） and CO2MB generated by the gas-water circulating-type generator. Appressodum formation in the 10 000-fold diluted BF solution containing both CO2MBs was less than that in CO2MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO2MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO2MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO2MB.
文摘A total of 2 088 marine microorganisms including 1 392 strains of bacteria and 696 strains of fungi were isolated from diverse marine environment such as the South Pole, the North Pole, and Qingdao tideland, etc. Through a systematic screening process involving the use of Pyricularia oryzae mode, 90 bacteria and 31 fungi strains demonstrating positive bioactivities were identified. The rates of active strains of marine bacteria and marine fungi were 6.5% and 4.5%, respectively. The relationships between the active strains and the sampling locations and hosts were studied. For marine bacteria, the three locations showing the highest rotes of active strains were 8.4% in the Zhujiang Estuary, 7.2% at the North Pole and 6.3% in the Bohai Sea. For marine fungi, the highest rates observed were 7.8% at the South Pole, 7.4% in the South China Sea and 6.8% at the Qingdao tideland. An analysis of the host showed that the three highest rates of active strain for marine bacteria were 8.2% for seawater from the Zhujiang Estuary, 8% for alga from the Qingdao tideland and 7.6% for sea mud from the North Pole. For marine fungi, the highest rates observed were 8.3% for Qingdao actiniae, 7.4% for South China Sea poriferan and 4.5% for soil of Qingdao Suaeda salsa. Four fungi and two bacteria samples were selected for further study because of their high bioactivity. They were found to be active towards several pathogenic microorganisms, and demonstrated stable genetic and thermal characteristics and conservation activities.
基金Supported by "Eleventh Five-Year" National Science and Technology Suppor Program(2007BAD65B022012BAD04B01)
文摘In order to clear the composition and distribution of physiological races of Pyricularia oryae in Heilongjiang Province, 299 single spore isolates of P. oryae collected from five rice regions （30 cities, counties or farms） in Heilongiiang Province form 2007 to 2011 were identified by seven differential varieties in Chi- na, and a total of seven groups with 31 physiological races had been identified. The results showed that ZA, ZD and ZB groups were the dominant groups in Hei- longjiang Province, with the occurrence frequencies of 34.8%, 31.1% and 16.1%, respectively. ZD5 was the dominant race with the oeeurrence frequency of 17.1% ; followed by ZA49 and ZD1 , with the occurrence frequencies of 13.7% and 10.7% , respectively. The types and compositions of physiological races of P. oryae varied with rice regions.
文摘Blast has been a continuous threat to finger millet production in semi-arid tropics.The disease is economically important and widespread in finger millet major growing areas of western,Nyanza and Rift valley in Kenya.Host resistance is the most economical and effective means of controlling the disease as finger millet is grown by resource-poor farmers.This study evaluated a hundred finger millet genotypes for resistance to blast at KALRO(Kenya Agricultural Research and Livestock Organization)Kakamega and Alupe,Kenya for two seasons in 2011/2012 in a lattice square design for two seasons each.Data on blast incidence and severity were measured.Data were analyzed using ANOVA(analysis of variance)and means separated using Duncan multiple range test(DMRT)at p<0.005.The results showed that disease severity was highest in early maturing varieties and lowest in the late maturing varieties.The most resistant genotypes were:GBK000702,GBK000513,GBK029869,GULU-E,GBK000752 and Busibwabo.Pearson correlation analysis between neck severity and physiological maturity was positively significant(r=-0.47).A strong positive correlation between finger severity and neck severity(r=0.87)was observed.These tolerant genotypes could be utilized as donor parents for breeding durable blast resistant varieties.
文摘Pyricularia oryzae is a fungal pathogen of rice.Few researches had been reported on the analysisof its genome, partly because the genomes can’t beseparated by general agarose gel electrophoresis.We herein report a technique to separatePyricularia oryzae genomic DNA by pulse-fieldgel electrophoresis(PFGE).The tested blast strain was 2539w.Chromosomal DNAs were directly prepared from
文摘Five triterpenoid saponins were isolated from the Chinese traditional medicine Eclipta prostrata L.. On the basis of their chemical properties and spectral data, they were identified as eclalbasaponins II(1), I(2), III(3), 3-O-[b-D-glucopyranosyl(12)-b-D-glucopyranosyl]-16a-ethoxy-olean-12-ene-28-oic acid-28-O-b-D-glu-copyranoside(4) and 3-O-[(2-O-sulfuryl-b-D-glucopyranosyl)(12)-b-D-glucopyranosyl]-echinocystic acid-28-O-b-D-glucopyranoside(5). Compounds 4 and 5 are new compounds and named eclalbasaponins XI and XII, respectively. Compounds 1 and 5 induced morphological deformation of Pyricularia oryzae mycelia.
