[Objective] This study aimed to investigate an outbreak of apple valsa canker （Valsa ceratosperma） in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commerc...[Objective] This study aimed to investigate an outbreak of apple valsa canker （Valsa ceratosperma） in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commercial apple or-chards in Qixia, Haiyang and Laiyang were selected to investigate the outbreak of applevalsa canker. [Result]The results showed that apple canker occurred seriously in Yantai apple producing area in 2011. The ratio of diseased plants with new canker scars was 68.20% and the ratio of dead plants infected with Valsa cer-atosperma was 2.76%. The average ratios of diseased branches and one-year-old dead branches were 23.98% and 10.74%, respectively. The percentage of orchards with more than 50% diseased plants accounted for 25%-30% of the total number of orchards investigated, and the overal prevalence situation was more serious than normal years. In the investigation, 967 new canker scars were observed, with an average of 2.32 canker scars per plant. Specifical y, 80.04% canker scars were de-veloped from pruning wounds; 60.29% canker scars were developed from previous scars. [Conclusion] The long-period precipitation in the autumn of 2010, low temper-ature in the winter of 2010 and the severe drought in the spring of 2011 might be the major factors causing the outbreak of apple valsa canker in Yantai apple pro-ducing area in 2011. Pruning wounds were the main infection entrances of V. cer-atosperma, and the recurrence in previous scars was the main reason for the out-break of apple canker in spring.展开更多
[Objective] Inhibition mechanism of the antifungal substances from Chaetomium globosum ND35 against pathogenic fungi of Valsa canker was investigated.[Method] The inhibitory effect of antifungal substances （AFS） pro...[Objective] Inhibition mechanism of the antifungal substances from Chaetomium globosum ND35 against pathogenic fungi of Valsa canker was investigated.[Method] The inhibitory effect of antifungal substances （AFS） produced by endophytic C. globosum ND35 on pathogenic fungi of Valsa canker was studied by means of dual culture,extraction,thin layer chromatography and bioassay of antifungal activity. [Result] The crude extracts of AFS could strongly inhibit Valsa sordida and V. mali. The suppression percentage of mycelial growth of two pathogenic fungi were 66.4% and 72.6%,respectively. The inhibition percentages of conidia germination of two pathogenic fungi were 92.2% and 80.4%,respectively. Separation of thin layer chromatography and bioassay of antifungal activity indicated that the fraction No.2 of AFS played an important role in the process of inhibition on pathogenic fungi,causal agents of Valsa canker. [Conclusion] The antifungal substances from C. globosum ND35 is potential for biological control on Valsa canker.展开更多
新疆阿克苏地区由Valsa mali var.pyri、Valsa sordida引起的腐烂病是制约库尔勒香梨发展的重要病害,为研究库尔勒香梨感染腐烂病后与防御酶活性的变化关系,以库尔勒香梨为试验材料,分别采集同一株树不同发病组织和不同发病程度枝条韧皮...新疆阿克苏地区由Valsa mali var.pyri、Valsa sordida引起的腐烂病是制约库尔勒香梨发展的重要病害,为研究库尔勒香梨感染腐烂病后与防御酶活性的变化关系,以库尔勒香梨为试验材料,分别采集同一株树不同发病组织和不同发病程度枝条韧皮部,研究其抗性相关酶活性变化。结果表明:病害在完全侵入组织后,SOD活性呈下降的趋势,在发病组织,POD、CAT活性最高,PAL在病健交界处活性最高。随着发病程度的增加,SOD活性整体呈先上升后下降的趋势,POD活性呈逐渐上升的趋势,CAT活性先下降后上升,PAL活性先上升后下降,PPO总体呈下降趋势。库尔勒香梨抗性相关酶活性呈现不同变化响应Valsa侵染。在Valsa与库尔勒香梨互作系统中,抗性酶可作为抗病性和检测病害指标,为检测库尔勒香梨腐烂病发病程度提供理论依据。展开更多
Pear Valsa canker is a fungal trunk disease caused by Valsa pyri. Phenolic compounds are ubiquitous in plants and usually contribute to plant resistance against biotic stress. To investigate the association between ph...Pear Valsa canker is a fungal trunk disease caused by Valsa pyri. Phenolic compounds are ubiquitous in plants and usually contribute to plant resistance against biotic stress. To investigate the association between phenolic compounds and level of resistance to V. pyri, we quantified the contents of individual phenolic compounds in the cortex and phloem of stems from 8 cultivars of Pyrus bretschneideri. Significant variation in the levels of all compounds was found among the cultivars. Correlation analysis revealed an inverse correlation between levels of arbutin and gallic acid with the degree of canker resistance. This suggested that these phenolic compounds are beneficial to V. pyri infection. These data could be valuable for breeding cultivars of P. bretschneideri with greater resistance to V. pyri.展开更多
Bacterial-fungal interactions are widespread in nature.We observed that pear orchards affected by Cytospora pyri(formerly Valsa pyri)were often accompanied with Erwinia amylovora.However,the relationship of the two pa...Bacterial-fungal interactions are widespread in nature.We observed that pear orchards affected by Cytospora pyri(formerly Valsa pyri)were often accompanied with Erwinia amylovora.However,the relationship of the two pathogens was unclear.The objective of this study was to determine whether the synergistic effect exists between E.amylovora and C.pyri.We first analyzed the coexistence frequencies of E.amylovora and C.pyri in pear trees.Virulence of the two pathogens,growth,physical interactions,amylovoran production,and expression of genes for amylovoran biosynthesis were conducted.Our results showed that E.amylovora and C.pyri could coexist on the same lesion and caused much more severe disease.We also found that E.amylovora could physically attach to C.pyri and the expression of amylovoran biosynthesis genes were up-regulated with fungal metabolite treatment.These results indicate that E.amylovora and C.pyri can cooperatively interact,which provides C.pyri with an opportunity to promote bacterial dispersal and production of virulence factor in E.amylovora.展开更多
林木腐烂病是苹果树、梨树和杨树等林木枝干的重要真菌性病害。为了筛选出对苹果树腐烂病菌Valsa mali var.mali、梨树腐烂病菌V.mali var.pyri和杨树腐烂病菌V.sordida等3种不同寄主腐烂病菌都能有效防控的杀菌剂,本研究开展室内毒力...林木腐烂病是苹果树、梨树和杨树等林木枝干的重要真菌性病害。为了筛选出对苹果树腐烂病菌Valsa mali var.mali、梨树腐烂病菌V.mali var.pyri和杨树腐烂病菌V.sordida等3种不同寄主腐烂病菌都能有效防控的杀菌剂,本研究开展室内毒力试验比较了7种杀菌剂对3种腐烂病病原菌菌丝生长和分生孢子萌发的抑制效果,并进一步通过田间活性测定试验比较7种杀菌剂对梨树腐烂病病斑扩展和分生孢子发生的防治效果,同时测定了增效剂8.6%聚乙二醇(PEG)对7种杀菌剂的增效作用。毒力测定结果表明,苯醚甲环唑、戊唑醇、吡唑醚菌酯和丙唑·多菌灵对3种腐烂病病原菌菌丝生长和分生孢子萌发的抑制作用较强,其中EC_(50)平均值最低的是苯醚甲环唑,而戊唑醇的MIC平均值最低,在0.33 mg/L浓度下对3种腐烂病病原菌的菌丝生长和分生孢子萌发抑制率均达到100%。田间试验结果表明,45%苯醚甲环唑SC、43%戊唑醇SC和35%丙唑·多菌灵SE对梨树腐烂病病斑扩展和分生孢子萌发的防治效果突出,其中45%苯醚甲环唑SC 30.00 mg/L对病斑扩展防治效果达到82.23%,孢子萌发抑制效果达到85.96%,田间防治效果最好。10%丙硫唑SC+8.6%PEG处理组对病斑扩展防治效果提高了15.39百分点,达到73.46%,分生孢子萌发抑制率提高了23.75百分点,达到83.06%,增效作用显著。本研究为苹果树、梨树和杨树等3种寄主腐烂病的化学防控提供了科学依据。展开更多
基金Supported by National Modern Industrial Technology System of Apple(CARS-28)National Natural Science Foundation of China(31000891)~~
文摘[Objective] This study aimed to investigate an outbreak of apple valsa canker （Valsa ceratosperma） in Yantai apple producing area in 2011 and analyze the major causes of the disease. [Method] In May 2011, 21 commercial apple or-chards in Qixia, Haiyang and Laiyang were selected to investigate the outbreak of applevalsa canker. [Result]The results showed that apple canker occurred seriously in Yantai apple producing area in 2011. The ratio of diseased plants with new canker scars was 68.20% and the ratio of dead plants infected with Valsa cer-atosperma was 2.76%. The average ratios of diseased branches and one-year-old dead branches were 23.98% and 10.74%, respectively. The percentage of orchards with more than 50% diseased plants accounted for 25%-30% of the total number of orchards investigated, and the overal prevalence situation was more serious than normal years. In the investigation, 967 new canker scars were observed, with an average of 2.32 canker scars per plant. Specifical y, 80.04% canker scars were de-veloped from pruning wounds; 60.29% canker scars were developed from previous scars. [Conclusion] The long-period precipitation in the autumn of 2010, low temper-ature in the winter of 2010 and the severe drought in the spring of 2011 might be the major factors causing the outbreak of apple valsa canker in Yantai apple pro-ducing area in 2011. Pruning wounds were the main infection entrances of V. cer-atosperma, and the recurrence in previous scars was the main reason for the out-break of apple canker in spring.
基金Supported by National Natural Science Foundation of China(30571489)Shandong Agricultural University Youth Science and Technology Innovation Fund Projects(23406)~~
文摘[Objective] Inhibition mechanism of the antifungal substances from Chaetomium globosum ND35 against pathogenic fungi of Valsa canker was investigated.[Method] The inhibitory effect of antifungal substances （AFS） produced by endophytic C. globosum ND35 on pathogenic fungi of Valsa canker was studied by means of dual culture,extraction,thin layer chromatography and bioassay of antifungal activity. [Result] The crude extracts of AFS could strongly inhibit Valsa sordida and V. mali. The suppression percentage of mycelial growth of two pathogenic fungi were 66.4% and 72.6%,respectively. The inhibition percentages of conidia germination of two pathogenic fungi were 92.2% and 80.4%,respectively. Separation of thin layer chromatography and bioassay of antifungal activity indicated that the fraction No.2 of AFS played an important role in the process of inhibition on pathogenic fungi,causal agents of Valsa canker. [Conclusion] The antifungal substances from C. globosum ND35 is potential for biological control on Valsa canker.
文摘新疆阿克苏地区由Valsa mali var.pyri、Valsa sordida引起的腐烂病是制约库尔勒香梨发展的重要病害,为研究库尔勒香梨感染腐烂病后与防御酶活性的变化关系,以库尔勒香梨为试验材料,分别采集同一株树不同发病组织和不同发病程度枝条韧皮部,研究其抗性相关酶活性变化。结果表明:病害在完全侵入组织后,SOD活性呈下降的趋势,在发病组织,POD、CAT活性最高,PAL在病健交界处活性最高。随着发病程度的增加,SOD活性整体呈先上升后下降的趋势,POD活性呈逐渐上升的趋势,CAT活性先下降后上升,PAL活性先上升后下降,PPO总体呈下降趋势。库尔勒香梨抗性相关酶活性呈现不同变化响应Valsa侵染。在Valsa与库尔勒香梨互作系统中,抗性酶可作为抗病性和检测病害指标,为检测库尔勒香梨腐烂病发病程度提供理论依据。
基金supported by the Special Fund for AgroScientific Research in the Public Interest(201203034)the Agriculture Research System of China(CARS-29-14)+1 种基金the National Natural Science Foundation of China(31401831)the Foundation of Discipline Capacity Promotion at AHAU(XKTS 2013010)
文摘Pear Valsa canker is a fungal trunk disease caused by Valsa pyri. Phenolic compounds are ubiquitous in plants and usually contribute to plant resistance against biotic stress. To investigate the association between phenolic compounds and level of resistance to V. pyri, we quantified the contents of individual phenolic compounds in the cortex and phloem of stems from 8 cultivars of Pyrus bretschneideri. Significant variation in the levels of all compounds was found among the cultivars. Correlation analysis revealed an inverse correlation between levels of arbutin and gallic acid with the degree of canker resistance. This suggested that these phenolic compounds are beneficial to V. pyri infection. These data could be valuable for breeding cultivars of P. bretschneideri with greater resistance to V. pyri.
基金supported by the Major Science and Technology Projects in Xinjiang,China(2023A02006).
文摘Bacterial-fungal interactions are widespread in nature.We observed that pear orchards affected by Cytospora pyri(formerly Valsa pyri)were often accompanied with Erwinia amylovora.However,the relationship of the two pathogens was unclear.The objective of this study was to determine whether the synergistic effect exists between E.amylovora and C.pyri.We first analyzed the coexistence frequencies of E.amylovora and C.pyri in pear trees.Virulence of the two pathogens,growth,physical interactions,amylovoran production,and expression of genes for amylovoran biosynthesis were conducted.Our results showed that E.amylovora and C.pyri could coexist on the same lesion and caused much more severe disease.We also found that E.amylovora could physically attach to C.pyri and the expression of amylovoran biosynthesis genes were up-regulated with fungal metabolite treatment.These results indicate that E.amylovora and C.pyri can cooperatively interact,which provides C.pyri with an opportunity to promote bacterial dispersal and production of virulence factor in E.amylovora.
