Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold s...Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold storage in Hebei Province.The fungus was consistently isolated from diseased fruit by routine tissue separation method,and shown to be the causal agent according to Koch postulates.Based on its morphology,molecular characteristics,pathogenicity and ITS sequence,the fungus was identified as Rhizoctonia solani.This study recorded postharvest fruit rot caused by Rhizoctonia solani on pear fruit in China.展开更多
The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent stra...The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.展开更多
分别基于7个烟草靶斑病菌株基因组中ITS-5.8S r DNA序列设计引物和探针;并对引物及探针特异性进行验证;建立检测体系并对接种烟草靶斑病菌的叶片和土壤中的烟草靶斑病菌进行检测。结果表明:所设计的引物及探针对R.solani AG-3具有特异性...分别基于7个烟草靶斑病菌株基因组中ITS-5.8S r DNA序列设计引物和探针;并对引物及探针特异性进行验证;建立检测体系并对接种烟草靶斑病菌的叶片和土壤中的烟草靶斑病菌进行检测。结果表明:所设计的引物及探针对R.solani AG-3具有特异性,检测体系可以检测出烟草叶片及土壤样品中的烟草靶斑病菌。接种烟草叶片的检测表明,接种后6h就可检测到强致病力菌株YC-9,12h后能检测到弱致病力菌株LF-2;获得了烟草靶斑病菌DNA质量的对数与添加菌丝量的对数之间的回归曲线方程,对不同月份土壤样品的测定结果表明烟草靶斑病菌在土壤中呈周年动态变化趋势。展开更多
Rice sheath blight disease （ShB）, caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subti...Rice sheath blight disease （ShB）, caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subtilis strain MBI 600, against rice ShB and for plant growth promotion. In greenhouse studies, four log concentrations of Integral （from 2.2×10^6 to 2.2×10^9 cfu/mL） were used as seed treatment （ST）. After 25 d, seedlings were dipped （SD） into Integral prior to transplanting. At 30 d after transplanting （DAT）, leaf sheaths were inoculated with immature sclerotia of the pathogen. At 45 DAT, a foliar spray （FS） with Integral was applied to some treatments. The fungicide control was 50% carbendazim at 1.0 g/L, and a nontreated control was also included. Overall, there were 10 treatments, each with five replications. ShB severity was rated at 52 DAT, and seedling height and number of tillers per plant were rated at 60 DAT. In 2009, two field trials evaluated Integral at 2.2×10^8 and 2.2×10^9 cfu/mL. Integral was applied as ST, and seedlings were produced in a nursery bed. After 32 d, seedlings were treated with Integral as SD and transplanted into 10 m^2 blocks. Foliar sprays were given at 45 and 60 DAT. There were seven treatments, each with eight replications arranged as a factorial randomized complete block design. At 20 DAT, the plots were broadcast inoculated with R. solani produced on rice grains. Seedling height before transplanting, ShB severity at 90 DAT, and grain yield at harvest were recorded. Integral at 2.2×10^9 cfu/mL provided significant increase of seedling heights over other treatments under greenhouse conditions. The Integral treatments of ST ＋ SD ＋ FS at 2.2×10^9 cfu/mL significantly suppressed ShB over other treatments. In field studies, Integral provided significant increase of seedling height in nursery, and number of tillers per plant, compared with the control. ShB severity was significantly suppressed with higher concentrations of Integral compared to lower concentrations. Grain yield were the highest at an Integral concentration of 2.2×10^9 cfu/mL. Overall, Integral significantly reduced ShB severity, enhanced seedling growth, number of tillers per plant and grain yield as ST ＋ SD ＋ FS at the concentration of 2.2×10^9 cfu/mL under the conditions evaluated.展开更多
The inhibition of lanthanum (La) to mycelial growth and three disease-related enzymes of Rhizoctonia solani were studied. The results showed that lanthanum inhibits the growth of Rhizoctonia solani strongly. EC_(50) a...The inhibition of lanthanum (La) to mycelial growth and three disease-related enzymes of Rhizoctonia solani were studied. The results showed that lanthanum inhibits the growth of Rhizoctonia solani strongly. EC_(50) and EC_(95) of La were 171.9 and 667.7 mg·L^(-1) measured in solid culture media respectively, while 111.4 and 500.7 mg·L^(-1) measured in liquid culture media respectively. Lanthanum also has activating effects on disease-related enzymes of the fungus such as pectinase, protease and cellulase. However, the quantity or the activity of the total enzymes decreases significantly because of the strong blockage of mycelial growth when the La_2O_3 concentration is over 50 mg·L^(-1), and the virulence of pathogen decreases as well.展开更多
基金supported by the National Key R&D Program of China(Grant No.2016YFD0400903–06)the earmarked fund for China Agriculture Research System(Grant No.CARS-29–19)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences。
文摘Pear is a fruit crop of worldwide importance and cold storage is an integral part of the production and distribution of pears.An uncharacterized fungal disease has been observed on‘Huangguan’pear fruit during cold storage in Hebei Province.The fungus was consistently isolated from diseased fruit by routine tissue separation method,and shown to be the causal agent according to Koch postulates.Based on its morphology,molecular characteristics,pathogenicity and ITS sequence,the fungus was identified as Rhizoctonia solani.This study recorded postharvest fruit rot caused by Rhizoctonia solani on pear fruit in China.
基金funded by the National Key Project for Research on Transgenic Biology,China(2016ZX08002001 to Zengyan Zhang)。
文摘The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.
文摘分别基于7个烟草靶斑病菌株基因组中ITS-5.8S r DNA序列设计引物和探针;并对引物及探针特异性进行验证;建立检测体系并对接种烟草靶斑病菌的叶片和土壤中的烟草靶斑病菌进行检测。结果表明:所设计的引物及探针对R.solani AG-3具有特异性,检测体系可以检测出烟草叶片及土壤样品中的烟草靶斑病菌。接种烟草叶片的检测表明,接种后6h就可检测到强致病力菌株YC-9,12h后能检测到弱致病力菌株LF-2;获得了烟草靶斑病菌DNA质量的对数与添加菌丝量的对数之间的回归曲线方程,对不同月份土壤样品的测定结果表明烟草靶斑病菌在土壤中呈周年动态变化趋势。
文摘Rice sheath blight disease （ShB）, caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subtilis strain MBI 600, against rice ShB and for plant growth promotion. In greenhouse studies, four log concentrations of Integral （from 2.2×10^6 to 2.2×10^9 cfu/mL） were used as seed treatment （ST）. After 25 d, seedlings were dipped （SD） into Integral prior to transplanting. At 30 d after transplanting （DAT）, leaf sheaths were inoculated with immature sclerotia of the pathogen. At 45 DAT, a foliar spray （FS） with Integral was applied to some treatments. The fungicide control was 50% carbendazim at 1.0 g/L, and a nontreated control was also included. Overall, there were 10 treatments, each with five replications. ShB severity was rated at 52 DAT, and seedling height and number of tillers per plant were rated at 60 DAT. In 2009, two field trials evaluated Integral at 2.2×10^8 and 2.2×10^9 cfu/mL. Integral was applied as ST, and seedlings were produced in a nursery bed. After 32 d, seedlings were treated with Integral as SD and transplanted into 10 m^2 blocks. Foliar sprays were given at 45 and 60 DAT. There were seven treatments, each with eight replications arranged as a factorial randomized complete block design. At 20 DAT, the plots were broadcast inoculated with R. solani produced on rice grains. Seedling height before transplanting, ShB severity at 90 DAT, and grain yield at harvest were recorded. Integral at 2.2×10^9 cfu/mL provided significant increase of seedling heights over other treatments under greenhouse conditions. The Integral treatments of ST ＋ SD ＋ FS at 2.2×10^9 cfu/mL significantly suppressed ShB over other treatments. In field studies, Integral provided significant increase of seedling height in nursery, and number of tillers per plant, compared with the control. ShB severity was significantly suppressed with higher concentrations of Integral compared to lower concentrations. Grain yield were the highest at an Integral concentration of 2.2×10^9 cfu/mL. Overall, Integral significantly reduced ShB severity, enhanced seedling growth, number of tillers per plant and grain yield as ST ＋ SD ＋ FS at the concentration of 2.2×10^9 cfu/mL under the conditions evaluated.
文摘The inhibition of lanthanum (La) to mycelial growth and three disease-related enzymes of Rhizoctonia solani were studied. The results showed that lanthanum inhibits the growth of Rhizoctonia solani strongly. EC_(50) and EC_(95) of La were 171.9 and 667.7 mg·L^(-1) measured in solid culture media respectively, while 111.4 and 500.7 mg·L^(-1) measured in liquid culture media respectively. Lanthanum also has activating effects on disease-related enzymes of the fungus such as pectinase, protease and cellulase. However, the quantity or the activity of the total enzymes decreases significantly because of the strong blockage of mycelial growth when the La_2O_3 concentration is over 50 mg·L^(-1), and the virulence of pathogen decreases as well.
