为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发...为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发病部位进行病原菌分离与培养后得到25株病原真菌,利用显微形态学观察将分离物代表菌株分为LJ1、LJ2和LJ3共3类真菌分离物。结合分子生物学方法及系统发育树构建,将LJ1类病原菌鉴定为镰孢菌属茄病镰孢菌,LJ2类病原菌为丝核菌属立枯丝核菌AG-4菌丝融合群的HGⅠ亚群(Rhizoctonia solani AG 4 HG-Ⅰ),LJ3类病原菌为镰孢菌属尖孢镰孢菌。采用幼苗刺伤接种法进行病原菌致病性评价,3类真菌分离物均能够侵染辣椒幼苗造成根腐病,且尖孢镰孢菌致病性最强。日喀则各地辣椒根腐病病原菌优势菌有差异,尖孢镰孢菌是优势致病菌,分离频率为52.0%;茄病镰孢菌分离频率为32.0%;立枯丝核菌分离频率为16.0%。西藏日喀则地区的辣椒根腐病是由尖孢镰孢菌、茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群复合侵染导致,茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群均是首次在西藏被分离鉴定。展开更多
Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses....Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses.An incidence of red rot disease was found in a P.yezoensis farm from mid-November to mid-December 2015 at Lianyungang,Jiangsu Province,China.Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen,leading to red rot symptoms.The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox 1).In artifi cial infection experiments on the P.yezoensis blades,the P.chondricola isolate was able to cause the same characteristic histopathology seen in natural infections.P.chondricola grew well at a wide range of temperatures in the range 8-31℃,salinities at 0-45 and pH 5-9.In an orthogonal test used to determine the effects of environmental factors(temperature,salinity,and zoospore concentration)on infection,the data revealed that temperature was the most important factor to affect red rot disease development,with the optimal conditions for disease expansion being 20℃,35 salinity,and a zoospore concentration of 10^6 zoospores/mL.The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia,which will provide support to maintain the healthy development of the Pyropia industry in China.展开更多
The perennial root of Astragalus membranaceus is used as a medicine, while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus . The screening and research of the pathogenic s...The perennial root of Astragalus membranaceus is used as a medicine, while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus . The screening and research of the pathogenic species and their characteristics could provide theoretical and practical basis for the control of this disease. A pathogenic strain was isolated and purified from the root part of four-year-old A. membranaceus , and identified by morphological and molecular biological methods as Fusarium oxysporum . This study will provide a theoretical basis for the research of the biological characteristics and control of F. oxysporum .展开更多
Recently, a new bacterial top rot disease of maize has frequently appeared in many areas of Yunnan Province, China. The pathogen of the disease was identified as Klebsiella pneumoniae （KpC4）, which is well known to ...Recently, a new bacterial top rot disease of maize has frequently appeared in many areas of Yunnan Province, China. The pathogen of the disease was identified as Klebsiella pneumoniae （KpC4）, which is well known to cause pulmonary and urinary diseases in humans and animals and occasionally exists as a harmless endophyte in plants. To evaluate the viru- lence of the maize pathogen to maize and mice, we inoculated maize and mice with routine inoculation and intraperitoneal injection respectively according to Koch＇s postulates. The results showed that KpC4 and the clinical strain K. pneumoniae 138 （Kp138） were all highly pathogenic to maize and mice and the strain re-isolated from diseased mice also caused typical top rot symptoms on maize by artificial inoculation. It is highlighting that a seemingly dedicated human/animal pathogen could cause plant disease. This is the first report of K. pneumoniae, an opportunistic pathogen of human/animal, could infect maize and mice. The findings serve as an alert to plant, medical and veterinarian scientists regarding a potentially dangerous bacterial pathogen infecting both plants and animals/humans. The maize plants in the field could serve as a reservoir for K. pneumoniae which might infect animals and probably humans when conditions are favorable. The new findings not only are significant in the developing control strategy for the new disease in Yunnan, but also serve as a starting point for further studies on the mechanism of pathogenesis and epidemiology of K. pneumoniae.展开更多
Pear is an important fruit crop in the world. An uncharacterized disease has been observed on pear fruits during cold storage ir~ Suning, Shenzhou, Xinji and other locations in Hebei Province, China. The incidence rat...Pear is an important fruit crop in the world. An uncharacterized disease has been observed on pear fruits during cold storage ir~ Suning, Shenzhou, Xinji and other locations in Hebei Province, China. The incidence rate of the disease has reached 10%, and sometimes up to 20%. A particular fungus was consistently isolated from the infected pear fruit and cultured. Based on its morphology, molecular characteristics, pathogenicity and ITS sequence, the fungus was identified as Athelia bombacina. To our knowledge, this is the first report of Athelia bombacina causing postharvest fruit rot on pear.展开更多
As the most famous perennial leguminous forage in the world, Medicago sativa L. ranks the first in both yield and nutritional value, and can be used for many years once planted in field production. However, root rot h...As the most famous perennial leguminous forage in the world, Medicago sativa L. ranks the first in both yield and nutritional value, and can be used for many years once planted in field production. However, root rot has become a very important reason for yield decrease and plant de-cline of alfalfa due to long service life. According to the research progress at home and abroad, the main pathogen distribution, harms and control methods of root rot in M. sativa at home and abroad were systematically expounded, in order to provide a theoretical basis for further research of the disease.展开更多
文摘为检测和鉴定引起西藏日喀则地区的辣椒根腐病病原菌种类,2024年7—9月从西藏日喀则白朗县巴扎乡彭仓村、桑珠孜区聂日雄乡盘孔村、江孜县达孜乡德吉村和拉孜县拉孜镇玉哲村4个区域采集了16份辣椒感病植株样品。采用常规组织分离法对发病部位进行病原菌分离与培养后得到25株病原真菌,利用显微形态学观察将分离物代表菌株分为LJ1、LJ2和LJ3共3类真菌分离物。结合分子生物学方法及系统发育树构建,将LJ1类病原菌鉴定为镰孢菌属茄病镰孢菌,LJ2类病原菌为丝核菌属立枯丝核菌AG-4菌丝融合群的HGⅠ亚群(Rhizoctonia solani AG 4 HG-Ⅰ),LJ3类病原菌为镰孢菌属尖孢镰孢菌。采用幼苗刺伤接种法进行病原菌致病性评价,3类真菌分离物均能够侵染辣椒幼苗造成根腐病,且尖孢镰孢菌致病性最强。日喀则各地辣椒根腐病病原菌优势菌有差异,尖孢镰孢菌是优势致病菌,分离频率为52.0%;茄病镰孢菌分离频率为32.0%;立枯丝核菌分离频率为16.0%。西藏日喀则地区的辣椒根腐病是由尖孢镰孢菌、茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群复合侵染导致,茄病镰孢菌和立枯丝核菌AG-4菌丝融合群的HGI亚群均是首次在西藏被分离鉴定。
基金Supported by the China Agriculture Research System(No.CARS-50)the National Natural Sciences Foundation of China(No.31372517)+2 种基金the Fundamental Research Funds for the Central Universities(No.201562018)the National Infrastructure of Fishery Germplasm Resources(No.2017DKA30470)the Project of Aoshan Scientific and Technological Innovation Program of Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses.An incidence of red rot disease was found in a P.yezoensis farm from mid-November to mid-December 2015 at Lianyungang,Jiangsu Province,China.Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen,leading to red rot symptoms.The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox 1).In artifi cial infection experiments on the P.yezoensis blades,the P.chondricola isolate was able to cause the same characteristic histopathology seen in natural infections.P.chondricola grew well at a wide range of temperatures in the range 8-31℃,salinities at 0-45 and pH 5-9.In an orthogonal test used to determine the effects of environmental factors(temperature,salinity,and zoospore concentration)on infection,the data revealed that temperature was the most important factor to affect red rot disease development,with the optimal conditions for disease expansion being 20℃,35 salinity,and a zoospore concentration of 10^6 zoospores/mL.The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia,which will provide support to maintain the healthy development of the Pyropia industry in China.
基金Supported by National Natural Science Foundation of China(No.21462044,No.30860036)
文摘The perennial root of Astragalus membranaceus is used as a medicine, while root rot is a main factor causing reduction of quality and commodity value of A. membranaceus . The screening and research of the pathogenic species and their characteristics could provide theoretical and practical basis for the control of this disease. A pathogenic strain was isolated and purified from the root part of four-year-old A. membranaceus , and identified by morphological and molecular biological methods as Fusarium oxysporum . This study will provide a theoretical basis for the research of the biological characteristics and control of F. oxysporum .
基金funded by the Maize Production System of Yunnan Province,China(2015KJTX002)
文摘Recently, a new bacterial top rot disease of maize has frequently appeared in many areas of Yunnan Province, China. The pathogen of the disease was identified as Klebsiella pneumoniae （KpC4）, which is well known to cause pulmonary and urinary diseases in humans and animals and occasionally exists as a harmless endophyte in plants. To evaluate the viru- lence of the maize pathogen to maize and mice, we inoculated maize and mice with routine inoculation and intraperitoneal injection respectively according to Koch＇s postulates. The results showed that KpC4 and the clinical strain K. pneumoniae 138 （Kp138） were all highly pathogenic to maize and mice and the strain re-isolated from diseased mice also caused typical top rot symptoms on maize by artificial inoculation. It is highlighting that a seemingly dedicated human/animal pathogen could cause plant disease. This is the first report of K. pneumoniae, an opportunistic pathogen of human/animal, could infect maize and mice. The findings serve as an alert to plant, medical and veterinarian scientists regarding a potentially dangerous bacterial pathogen infecting both plants and animals/humans. The maize plants in the field could serve as a reservoir for K. pneumoniae which might infect animals and probably humans when conditions are favorable. The new findings not only are significant in the developing control strategy for the new disease in Yunnan, but also serve as a starting point for further studies on the mechanism of pathogenesis and epidemiology of K. pneumoniae.
基金supported by a grant from the National Key R&D Program of China (2016YFD0400903-06)the earmarked fund for China Agriculture Research System (CARS-29-19)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences (CAAS-ASTIP)
文摘Pear is an important fruit crop in the world. An uncharacterized disease has been observed on pear fruits during cold storage ir~ Suning, Shenzhou, Xinji and other locations in Hebei Province, China. The incidence rate of the disease has reached 10%, and sometimes up to 20%. A particular fungus was consistently isolated from the infected pear fruit and cultured. Based on its morphology, molecular characteristics, pathogenicity and ITS sequence, the fungus was identified as Athelia bombacina. To our knowledge, this is the first report of Athelia bombacina causing postharvest fruit rot on pear.
基金Supported by Guiding Science and Technology Plan of Daqing City(zd-2017-69)
文摘As the most famous perennial leguminous forage in the world, Medicago sativa L. ranks the first in both yield and nutritional value, and can be used for many years once planted in field production. However, root rot has become a very important reason for yield decrease and plant de-cline of alfalfa due to long service life. According to the research progress at home and abroad, the main pathogen distribution, harms and control methods of root rot in M. sativa at home and abroad were systematically expounded, in order to provide a theoretical basis for further research of the disease.
