Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical a...Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.展开更多
Fire blight, caused by Erwinia amylovora, is a devastating disease of apples and pears, causing enormous economic losses around the world. The disease is indigenous to North America and has spread to more than 50 coun...Fire blight, caused by Erwinia amylovora, is a devastating disease of apples and pears, causing enormous economic losses around the world. The disease is indigenous to North America and has spread to more than 50 countries since its discovery in 1870 s. Recent reports of the disease in China's neighboring countries, including South Korea, Kyrgyzstan, and Kazakhstan, pose great threat to the world's leading producer of apples and pears. This mini-review intends to provide an update on the disease, pathogen biology, epidemiology, and control. It will also provide some perspectives and suggestions for the apple and pear industry and growers in China, which will face the imminent threat of this devastating disease.展开更多
Since several Asian pear species are considered to be potential source of fire blight resistance, we crossed “Doyenné du Comice”, the susceptible European cultivar, with four Asian pear species. The aim of the ...Since several Asian pear species are considered to be potential source of fire blight resistance, we crossed “Doyenné du Comice”, the susceptible European cultivar, with four Asian pear species. The aim of the study was to establish the level of resistance of each genotype and the mode of transmission of fire blight resistance to each F1 full-sib progeny. The best sources of resistance were P. ussuriensis 18 and P. ussuriensis var. ovoidea 8 ranked to resistant and highly resistant, respectively. Although pear resistance to fire blight is suggested to be polygenic, distribution of phenotypes in “Doyenné du Comice” × P. ussuriensis var. ovoidea 8 hybrid family suggests the possibility of monogenic inheritance with the dominance of resistance derived from P. ussuriensis var. ovoidea 8. Polygenic inheritance of pear resistance to fire blight was identified in cross combinations of “Doyenné du Comice” with P. pyrifolia 6, and contributed by the major gene, with P. ussuriensis 18 and P. calleryana 12. Transgressive segregation was observed within the progenies of susceptible, moderately susceptible and resistant parents.展开更多
利用形态特征和基因序列分析对梨火疫病病原菌进行鉴定筛选,以期为河西灌区早酥梨火疫病诊断和制定防治策略提供科学依据。采用平板划线法,对引起河西灌区张掖市梨火疫病的病原菌进行了分离、鉴定及田间药剂筛选。结果表明,经致病性测定...利用形态特征和基因序列分析对梨火疫病病原菌进行鉴定筛选,以期为河西灌区早酥梨火疫病诊断和制定防治策略提供科学依据。采用平板划线法,对引起河西灌区张掖市梨火疫病的病原菌进行了分离、鉴定及田间药剂筛选。结果表明,经致病性测定,分离物F2为梨火疫病病原菌。病原菌鉴定为革兰氏染色阴性,菌落呈半球形隆起,乳白色,粘性,边缘整齐,表面光滑湿润,在28℃培养3 d后菌落直径3~4 mm,菌体杆状,大小为(0.9~1.8)μm×(0.6~1.5)μm,以单生为主,有时成双或3~4个连成短链状。根据培养性状、形态特征及基因序列分析,F2鉴定为解淀粉欧文氏菌(Erwinia amylovora)。田间农药筛选表明,喷药后15 d 3%噻霉酮水分散粒剂1000倍液防效最高,为61.9%,喷药后30 d 4%春雷霉素水剂1200倍液防效最高,为62.4%,其他各处理防效在50%以上;可见3%噻霉酮水分散粒剂1000倍液和4%春雷霉素水剂1200倍液2种药剂均可在生产中推广使用。展开更多
文摘Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program.
基金supported by the National Key R&D Program of China(2016YFC1201200)the National Natural Science Foundation of China(31500107 and 31772231)
文摘Fire blight, caused by Erwinia amylovora, is a devastating disease of apples and pears, causing enormous economic losses around the world. The disease is indigenous to North America and has spread to more than 50 countries since its discovery in 1870 s. Recent reports of the disease in China's neighboring countries, including South Korea, Kyrgyzstan, and Kazakhstan, pose great threat to the world's leading producer of apples and pears. This mini-review intends to provide an update on the disease, pathogen biology, epidemiology, and control. It will also provide some perspectives and suggestions for the apple and pear industry and growers in China, which will face the imminent threat of this devastating disease.
文摘Since several Asian pear species are considered to be potential source of fire blight resistance, we crossed “Doyenné du Comice”, the susceptible European cultivar, with four Asian pear species. The aim of the study was to establish the level of resistance of each genotype and the mode of transmission of fire blight resistance to each F1 full-sib progeny. The best sources of resistance were P. ussuriensis 18 and P. ussuriensis var. ovoidea 8 ranked to resistant and highly resistant, respectively. Although pear resistance to fire blight is suggested to be polygenic, distribution of phenotypes in “Doyenné du Comice” × P. ussuriensis var. ovoidea 8 hybrid family suggests the possibility of monogenic inheritance with the dominance of resistance derived from P. ussuriensis var. ovoidea 8. Polygenic inheritance of pear resistance to fire blight was identified in cross combinations of “Doyenné du Comice” with P. pyrifolia 6, and contributed by the major gene, with P. ussuriensis 18 and P. calleryana 12. Transgressive segregation was observed within the progenies of susceptible, moderately susceptible and resistant parents.
文摘利用形态特征和基因序列分析对梨火疫病病原菌进行鉴定筛选,以期为河西灌区早酥梨火疫病诊断和制定防治策略提供科学依据。采用平板划线法,对引起河西灌区张掖市梨火疫病的病原菌进行了分离、鉴定及田间药剂筛选。结果表明,经致病性测定,分离物F2为梨火疫病病原菌。病原菌鉴定为革兰氏染色阴性,菌落呈半球形隆起,乳白色,粘性,边缘整齐,表面光滑湿润,在28℃培养3 d后菌落直径3~4 mm,菌体杆状,大小为(0.9~1.8)μm×(0.6~1.5)μm,以单生为主,有时成双或3~4个连成短链状。根据培养性状、形态特征及基因序列分析,F2鉴定为解淀粉欧文氏菌(Erwinia amylovora)。田间农药筛选表明,喷药后15 d 3%噻霉酮水分散粒剂1000倍液防效最高,为61.9%,喷药后30 d 4%春雷霉素水剂1200倍液防效最高,为62.4%,其他各处理防效在50%以上;可见3%噻霉酮水分散粒剂1000倍液和4%春雷霉素水剂1200倍液2种药剂均可在生产中推广使用。
