10 June 2020, Volume 50 Issue 3
    

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    ETIOLOGY
  • Identification of Rhizopus soft rot of citrus
    CHEN Jiang-hua, WANG Xuan-xuan, CUI Xue-jing, LIN Yang, CHENG Jia-sen, XIE Jia-tao, FU Yan-ping
    Acta Phytopathologica Sinica. 2020, 50(3): 255-260. https://doi.org/10.13926/j.cnki.apps.000323
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Post-harvest diseases cause great losses to citrus industry. In this study, pathogen was isolated and identified from diseased fruits collected from Chenggu County, Shannxi Province in 2018. Strain CBS1 could infect Satsuma mandarin, Ponkan, Orah and Lane Late navel orange fruits and cause rot disease. Strain CBS1 and the strains recovered from the inoculated materials were identified as Rhizopus stolonifer based on the morphologi-cal characteristics and ITS sequence analysis. This is the first report that R. stolonifer infects citrus fruit, and the results will help to control post-harvest decay of citrus.
  • Identification of the pathogen causing spot blight on Paris polyphylla Smith var.chinensis
    FU Rong-tao, CHEN Cheng, WANG Jian, CHEN Xue-juan, LUO Xi, LU Dai-hua
    Acta Phytopathologica Sinica. 2020, 50(3): 261-266. https://doi.org/10.13926/j.cnki.apps.000324
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In 2018, a new spot blight disease on leaf of Paris polyphylla Smith var. chinensis was found with the incidence of about 35% or the whole leaf collapsed at favorite whether conditions in Wenchuan county, Sichuan Province. The causal agent, was isolated by tissue isolation method, and pathogenicity was tested follo-wing reisolation of the pathogen from the diseased leaves to satisfy Koch′s rule. The pathogen was identified based on morphological characteristics and sequence analysis of rDNA-ITS region and RPB2 gene. The results showed that the colony morphology, pycnidia and conidia of the isolates were similar to those of Didymella sp.. The sequences of ITS-RPB2 genes showed 100% identities with D. glomerata (No. FJ427013 and GU371781). Therefore, D. glomerata was identified as the pathogen causing the spot blight on leaf of Paris polyphylla Smith var. chinensis.
  • Identification of causal agent of apple, walnut and poplar Valsa canker disease in partial areas of Xinjiang
    LIU Chu-rong, DONG Yue, LI Ying-bin, JIANG Na, ZHU Tian-sheng, LI Zhi-jun, SONG Su-qin, LI Jian-qiang, LUO Lai-xin
    Acta Phytopathologica Sinica. 2020, 50(3): 267-275. https://doi.org/10.13926/j.cnki.apps.000461
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Tree canker disease is quite common on forest and fruit trees in Xinjiang and has been becoming more serious in recent years. We investigated Valsa disease on apple, walnut and poplar trees in Aksu, Khotan, Ili, Kashgar and Korla, which occurred to a certain degree, and collected the diseased samples from 14 locations for pathogen isolation. The results showed that the main pathogens identified on apple tree samples were Valsa mali var. mali (isolation frequency was 64.5%), V. mali var. pyri (25.8%), V. malicola (3.2%) and V. nivea (6.5%). The V. sordida (83.3% and 96%) and V. nivea (16.7% and 4%) were obtained from walnut and poplar tree samples, respectively. In pathogenicity test on detached branches and fruits, all strains could infect their corresponding original host plant. In conclusion, Valsa mali var. mali is the main pathogen caused Valsa canker on apple, while V. sordida is the major one caused Valsa canker on walnut and poplar in partial areas of Xinjiang. Meanwhile, we speculate a potential risk of cross infection among these three kinds of trees because the diseased poplar branches are used as support wood in orchard.
  • Colletotrichum sublineola, the main pathogen of sorghum anthracnose in Sichuan province
    WANG Yi-fu, LI Qiang, LI Wang-long, NI Xian-lin, LONG Wen-jing, LIU Guo-qing, ZENG Rong-yao, FAN Jing, HUANG Yan-yan, GONG Guo-shu, ZHAO Gan-lin, WANG Wen-ming
    Acta Phytopathologica Sinica. 2020, 50(3): 276-285. https://doi.org/10.13926/j.cnki.apps.000321
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Sorghum is a major cash crop in Sichuan province, it is often seriously infected by anthracnose disease. Colletotrichum graminicola was even considered as the pathogen of sorghum anthracnose in previous literatures. In recent literatures, C. sublineola, rather than C. graminicola was identified as the causal pathogen of sorghum anthracnose based on molecular biology and genomic analysis. In order to classify the causal pathogen of sorghum anthracnose in Sichuan province and other sorghum-growing areas in China, 198 samples were collected from 11 regions such as Luzhou Lu County in Sichuan Province and 6 other provinces and cities such as Chongqing, from which 225 fungal strains were isolated. Based on morphological observation, ITS and GAPDH gene sequence analysis and adjacent tree construction, 215 strains isolated from 17 regions belong to C. sublineola with crescent shaped spores, and the resting 10 strains from other two regions belong to C. cliviicola with rhabdoid spores. It is further proved that 17 representative strains of anthracnose generated from different regions have the similar morphological characteristics and belong to C. sublineola by phylogenetic of polygenes (CHS, ACT, TUB2). These data suggest that the morphology of conidia and appresoria and the genes of ITS, GAPDH CHS, ACT and TUB2 can be used for identification of sorghum anthracnose. Finally, all of the C. sublineola strains, rather than C. cliviicola, showed pathogenic on three common sorghum varieties. The results showed that C. sublineola was the pathogen of sorghum anthracnose in Sichuan province. Furthermore, C. sublineola strain ZG-FS-1, the most infectious pathogen in 19 representative strains, was used to screen the resis-tance resources of sorghum, and we found that variety 402B show the strongest resistance against sorghum anthracnose, indicating that it has application potential in sorghum anthracnose resistance breeding.
  • Identification of multiple viruses infecting watermelon in Kaifeng and Zhongmu of Henan Province by next generation sequencing (NGS)
    JIANG Jun, WU Nan, XIN Min, CAO Meng-ji, WANG Xi-feng
    Acta Phytopathologica Sinica. 2020, 50(3): 286-291. https://doi.org/10.13926/j.cnki.apps.000418
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    During 2015 and 2016, severe viral disease occurred in watermelon fields in Kaifeng and Zhongmu, Henan Province. Complex symptoms include yellowing, fern leaves, shrinking, curling, topmost upwarping, fruit shrunking and fuzziness of fruit pattern, which lead to difficulty for identifying pathogens. In this research, we combined small RNA sequencing and bioinformatic analysis to reveal the viruses in collected symptomatic watermelon samples. Ultimately, eight viruses were discovered including Zucchini yellow mosaic virus (ZYMV), Melon aphid-borne yellows virus (MABYV), Watermelon mosaic virus (WMV), Cucumber green mottle mosaic virus (CGMMV) and Citrullus lanatus cryptic virus (CiLCV) which have been reported in China. Other three new viruses, Watermelon virus A (WVA), Watermelon crinkle leaf-associated virus 1 (WCLaV-1) and Watermelon crinkle leaf-associated virus 2 (WCLaV-2) reported by our laboratory in recent years, were also detected in the samples. After testing of 66 samples collected from different fields by RT-PCR, we found WMV, CiLCV and ZYMV as the three most common viruses in samples, with frequency 61%, 56% and 52%, respectively. Meanwhile, we also found most samples infected by the complex viruses with 68% of infection rate.
    • CELL BIOLOGY, PHYSIOLOGY, BIOCHEMISTRY, AND MOLECULAR BIOLOGY
  • Identification and regulation analysis of genes encoding extracellular cellulase in soybean pathogen Xanthomonas axonopodis pv. glycines
    SU Ru-yi, WANG Hong-jie, DAI Xiao-yu, GAO Si-han, WANG Qing-yi, FENG Chao-ying, ZHANG Ping-hua, GUO Wei
    Acta Phytopathologica Sinica. 2020, 50(3): 292-300. https://doi.org/10.13926/j.cnki.apps.000470
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The genes encoding extracellular cellulase are different and diverse in plant pathogenic Xanthomonas. Extracellular cellulase contributes to the virulence of Xanthomonas axonopodis pv. glycines (Xag), but its encoding genes and the underlying molecular regulatory mechanism are unclear. In order to identify the genes encoding extracellular cellulase in Xag, 6 candidate genes were screened from the whole genome of strain NEAU001. Ectopic expression assay showed that EngXCA and Egl2 hydrolyzed carboxymethylcellulose, and the enzyme activity assay showed that engXCA and egl2 played the major role in the extracellular cellulase activity in Xag. In addition, the enzyme activity assay of 10 mutants in which the core virulence regulatory gene was deleted revealed that the extracellular cellulase activity of Xag was positively regulated by diffuse signal factor (DSF) signaling pathway and the global regulator Clp (Crp-like protein). qRT-PCR experiments further confirmed that both RpfF and Clp positively regulated engXCA and egl2 at the mRNA levels. Taken together, these results suggest that the DSF signaling pathway may regulate the expression of engXCA and egl2 through Clp, resulting in the regulation of the extracellular cellulase activity in Xag.
  • Functional analysis of lqp0812-lqp0813 genes of the two-component system from Lonsdalea quercina subsp. populi
    ZHENG Ze-yang, LI Ai-ning, CHANG Ju-pu, HE Wei
    Acta Phytopathologica Sinica. 2020, 50(3): 301-310. https://doi.org/10.13926/j.cnki.apps.000429
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Poplar canker disease caused by Lonsdalea quercina subsp. populi is a bacterial disease that seriously threatens the production of Populus × euramericana plants. The two-component system is one of the most important signal transduction pathways and plays a crucial role in the growth, reproduction, adaption, stress tolerance and pathogenicity of bacteria. To explore the function of two-component system encoding genes in L. quercina, this study used homologous recombination to carry out deletion mutations on the two-component system encoding genes lqp0812-lqp0813 in strain N-5-1, and studied their biological functions. Compared with the wild-type strain, the growth rate, tolerances to heavy metal stress, salt stress, osmotic stress and pathogenicity were not changed in Δlqp0812 and Δlqp0813 mutants. However, the swimming motility was significantly impaired in Δlqp0812 mutant than that of the wild-type. In addition, the biofilm formation, hydrogen peroxide and antibiotic resistance were significantly increased in Δlqp0812 and Δlqp0813 mutants compared with the wild-type. qRT-PCR analysis showed that the expression levels of the efflux pump genes acrA, mdtB and aaeB were greatly increased in the lqp0812 and lqp0813 deletion mutants. These results indicated that lqp0812 is involved in the swimming motility of L. quercina subsp. populi, and lqp0812 and lqp0813 negatively regulated biofilm formation and tolerance to H2O2 and antibiotic stress together.
  • The identification of virus diseases of faba bean in Yangzhou and cloning and sequence analysis of the full-length genome of vicia cryptic virus M Yangzhou isolate
    ZHANG Kun, XU Hong-mei, ZANG Ying, ZHUANG Xin-jian, GAN Hai-feng, CHEN Wen, HE Zhen
    Acta Phytopathologica Sinica. 2020, 50(3): 311-319. https://doi.org/10.13926/j.cnki.apps.000422
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    The field-grown faba bean samples exhibiting virus-like symptoms were collected and used for RNA extraction. Then, the siRNA was separated and used for siRNA library construction. After sequencing, velvet assembly, and blastn analysis, we found that collected faba bean samples were infected by 4 different viruses, which included VCV-M, vicia cryptic virus (VCV), milk vetch dwarf virus (MDV), and clover yellow vein virus (ClYVV). Among them, there are 14 VCV-M related contigs. As we know, the Amalgaviridae is a recently recognized family of dsRNA viruses that includes four species of plant viruses. RT-PCR amplification generated the 3 434 nt genome of VCV-M-YZ, of which the 5′-UTR and 3′-UTR were 142 nt and 117 nt, respectively. The 5′-UTR and 3′-UTR have high A+U content and form higher secondary structures, as well as the 5′-UTR and 3′-UTR of southern tomato virus, which is the representative virus of Amalgavirus. All this implies the specific characteristic of Amalgavirus replication. The sequences identity of VCV-M-YZ and reported VCV-M were 98%, and phylogenetic analyses showed that VCV-M-YZ and VCV-M belong to the same species, without obvious difference related to geographical distribution. Our studies enrich the genome genetic information of the VCV-M population, and provide basics of further research and supervisory control of VCV-M.
    • GENETICS OF DISEASERESISTANCE AND PATHOGENICITY
  • Genetic diversity of Pratylenchus neglectus populations on wheat in China
    YU Jia-rong, WANG Ya-dong, LI Hong-mei, ZHOU Xiao-qing, WANG Xuan
    Acta Phytopathologica Sinica. 2020, 50(3): 320-328. https://doi.org/10.13926/j.cnki.apps.000426
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    In order to clarify the genetic diversity of Pratylenchus neglectus populations in China, the genetic structure and genetic differentiation of 9 geographical populations were analyzed using the mtCOI gene as the marker. The results showed that a total of 101 mtCOI sequences were obtained from 9 populations, 28 variable nucleotide sites were discovered, and 14 haplotypes were formed. The haplotype H1 was the most common one shared by 59 individuals from 7 populations, which was speculated might be the ancestral haplotype. All the geographical populations showed the moderate genetic diversity at the species level (HT = 0.706±0.131), and the cluster analysis showed that they could be divided into two groups, as the Group Ⅰ and Group Ⅱ. The AMOVA analysis revealed that the genetic differentiation at the whole level of P. neglectus populations was mainly derived from the inter-populations. The Mantel test showed that the genetic distance among P. neglectus populations was positively correlated with their geographical distance, although there was no significant correlation between the genetic differentiation and the geographical distance among different populations. Both the neutrality test and the mismatch distribution test revealed that the historical dynamics of P. neglectus populations at the whole level as well as at the two-groups level were relatively stable.
  • Distribution and genetic diversity analysis of Trichotylenchus changlingensis in spring maize regions
    GUO Ning, QI Fang, LIU Ying, MA Hong-xia, LIU Shu-sen, SHI Jie
    Acta Phytopathologica Sinica. 2020, 50(3): 329-336. https://doi.org/10.13926/j.cnki.apps.000415
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    To determine the distribution of Trichotylenchus changlingensis in different geographical populations, in 2018, nematodes were isolated and identified from the rhizosphere soil of maize in 118 regions of Heilongjiang, Jilin, Liaoning, Hebei, Inner Mongolia and Gansu provinces (autonomous regions). The results showed that the nematodes were isolated from 20 soil samples in 6 provinces (autonomous regions) with isolation frequency of 17.0%. Sixteen highly polymorphic and reproducible ISSR primers were screened out and were used to amplify the 20 T. changlingensis isolates. A total of 93 polymorphic bands were obtained with a polymorphism ratio of 93.55%. The genetic differentiation coefficient (Gst) was 0.4771, indicating that the inter-group component accounted for 47.71% of the total variation,while the inner-group component accounted for 52.29%. The gene flow (Nm) was 0.5479 indicating that there was a less gene flow among different geographical populations. But there was genetic differentiation of some extent among groups. UPGMA cluster analysis showed that the T. changlingensis was rich in genetic diversity and there was no significant correlation between genetic distance and geographical distance.
    • EPIDEMIOLOGY AND ECOLOGY
  • Analysis oninitial infection sources of sesame bacterial wilt under the interplanting mode of citrus-sesame
    LI Xin-shen, HUANG Xiao-mei, XIAO Yun-ping, WEI Lin-gen, HUANG Rui-rong, HUA Ju-ling
    Acta Phytopathologica Sinica. 2020, 50(3): 337-344. https://doi.org/10.13926/j.cnki.apps.000322
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    An outbreak of sesame bacterial wilt caused by Ralatonia solanacearum was observed after first interplanting of citrus-sesame in an 11-years old orange orchard. To investigate the original infection pathogen, a strain JXRs02 was screened from the tissues of sesame infected with Ralstonia solanacearum. By morphology, molecular biology, and cluster analysis, JXRs02 was identified as R. solanacearum phylotypeⅠ. Four kinds of weeds including Amaranthus blitum, Alligator alternanthera, Feather cockscomb and Erigeron canadensis appeared in the orange orchard were inoculated with strain JXRs02 by pin prick. The results showed that JXRs02 could infect and cause wilt symptoms in Am. blitum. And the pathogen in the infected tissues of Am. blitum was identified as R. solanacearum by Loop-mediated isothermal amplification (LAMP). According to Koch’s postulates, the molecular biological methods were applied to verify that the pathogenic strains which are pathogenic to the Am. blitum or the pathogen causing the symptoms of sesame wilt are the R. solanacearum strains of phylotype I. Meanwhile, the results also showed that R. solanacearum isolated from the infected tissues of sesame could multiply in the rhizospheric soil of Am. blitum, Al. alternanthera, F. cockscomb and E. canadensis. These results indicated that Am. blitum, Al. alternanthera, F. cockscomb and E. canadensis may be the intermediate host of R. solanacearum, and the pathogen accumulated in its rhizospheric soil may be the primary source of R. solanacearum after citrus trees were interplanted with sesame cultivars. These data could provide scientific guidance on disease control strategies of bacterial wilt disease on crops.
  • Investigation on natural incidence of sugarcane white leaf in different varieties and crop cycles
    ZHANG Rong-yue, WANG Xiao-yan, HUANG Ying-kun, SHAN Hong-li, LI Jie, LI Wen-feng, CANG Xiao-yan, YIN Jiong, LUO Zhi-ming
    Acta Phytopathologica Sinica. 2020, 50(3): 345-350. https://doi.org/10.13926/j.cnki.apps.000430
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Sugarcane white leaf (SCWL) is a devastating disease caused by phytoplasmas, which is extremely harmful to sugarcane production. In order to clarify the occurrence regularity of SCWL in different cultivars and different crop cycles, in 2018, we conducted field investigation and nested PCR detection of SCWL in cane-planting areas of Mangweng and Hepai in Gengma, where SCWL was the most serious in China. The results of field investigation showed that the natural incidence rate of different varieties was different. The average disease incidence rate in Yuetang60 was the highest (73.50%) while Liucheng05-136 had the lowest (13.67%). The na-tural incidence rate in newly planted sugarcane was the lowest (32.38%), whereas, in the three-year ratoon sugarcane it was the highest (64.33%). The results of pathogen detection showed that the positive detection rate in all varieties was above 90%. The positive detection rate of Yingyu91-59 was the lowest (90.95%) and Liucheng05-136 was the highest (96.67%), the positive detection rate of asymptomatic samples was 81.53%, and the two and three-year ratoon sugarcane had the highest positive detection rate (96.67%). The results of this study showed that the incidence of SCWL increased with the increase of crop cycle, and the field investigation based on white leaf symptoms could not accurately reflect the actual occurrence of SCWL.
    • PLANT DISEASE AND CONTROL
  • Functional analysis of the ferric uptake regulator gene furA in Acidovorax citrulli
    WU Lin-na, YAN Jian-pei, BAI Xue, JI Wei-qin, ZHANG Xiao-xiao, YANG Yu-wen, GUAN Wei, ZHAO Ting-chang
    Acta Phytopathologica Sinica. 2020, 50(3): 351-361. https://doi.org/10.13926/j.cnki.apps.000457
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    Ferric uptake regulator (Fur) is a major regulator of regulating iron metabolism, which also affects oxidative stress and pathogenicity in bacteria. Acidovorax citrulli (Ac) has two Fur proteins whose functions are as yet unclear. The gene encoding one of them, furA, was addressed in this study. The deletion mutant of the furA gene (ΔfurA) in Aac5 was constructed by homologous recombination. And the virulence and other related biological phenotypes of mutant ΔfurA and its complementary strain ΔfurAcomp were measured comparing with the wild type Aac5. The results showed that the virulence, growth, swimming motility and siderophore production of ΔfurA were significantly reduced, while the biofilm formation and sensitivities to Fe3+, hydrogen peroxide and streptonigrin were significantly improved. Reverse transcription quantitative PCR analysis showed that furA affected the expression of genes involving in iron metabolism, stress reaction and virulence. In summary, FurA played an important regulatory role in pathogenic process, iron metabolism and other biological traits in Ac.
    • RESEARCH NOTES
  • Construction of differential host for the asparagus stem blight pathogen
    CHEN Jian, LAN Bo, ZHONG Ling, ZHOU Jin-song, YI Ke-xian, LI Xiang-min, YANG Ying-qing
    Acta Phytopathologica Sinica. 2020, 50(3): 362-368. https://doi.org/10.13926/j.cnki.apps.000327
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    Asparagus stem blight is a regional devastating disease caused by Phomopsis asparagi (Sacc.) Bubak. In order to construct the differential host for its pathogen, resistance tests of Asparagus officinalis Linn germplasms against P. asparagi were carried out at the seedling stage, followed by phylogenetic analysis based on the resistance level. A differential host set for differentiating the pathogen population was established and the pathogenicity differentiation of isolates from six provinces was distinguished using this differential host set. The results showed that thirty-one A. officinalis germplasms were classified into four groups as similarity coefficient of the disease resistance was 0.7. Group I was composed of eleven cultivars including “JK701”. Group II was composed of fourteen cultivars including “Jingganghong”. Group III was composed of three cultivars including “TC”. Group IV was composed of three cultivars including “TX-4/SD”. “JK701”, “Jingganghong”, “TC” and “TX-4/SD” were selected as the differential host set according to accessibility of germplasm resources. The pathogenicity of forty-eight isolates from six provinces was determined using the differentials and showed obvious divergence. All the isolates were grouped into various pathogenic races. Isolation frequency of race C1 was highest, accounting for 20.83%. Races A1 , A2 followed and isolation frequency of the both races was 18.75%. Isolation frequency of races A4, B3, C2, D1, and E1 was zero. The distribution of race types among these provinces was slightly different. In Jiangxi Province, the dominant race was B2. A1, A2 and B1 were the dominant races in Fujian Province, A1 and C1 in Shandong Province, B1 and C1 in Shanxi Province, and A2, A3, and C1 in Hainan Province. Altogether, differential hosts constructed in this study could distinguish the pathogenicity differentiation among P. asparagi isolates, which revealed that the above four cultivars were quite qualified for the differential host for the asparagus stem blight pathogen.
  • Identification of the pathogen causing rust disease on Monstera deliciosa in Inner Mongolia
    YANG Xiao-po, LIU Tie-zhi, Li Jing
    Acta Phytopathologica Sinica. 2020, 50(3): 369-372. https://doi.org/10.13926/j.cnki.apps.000326
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    Monstera deliciosa (Araceae) is a tropical American rainforest monocotyledon which is well-known as ornamental foliage plant introduced into many parts of the world. Rust disease on M. deliciosa was found in Chifeng, Inner Mongolia in 2019. Morphological characteristics of the rust indicated that it was closely related to Puccinia paullula on Amorphophallus spp. in Philippines. Phylogenetic analysis of the LSU (ribosomal DNA Large Subunit) sequence indicated highly homologous to P. paullula (KY764151 and KX999886). The ITS (Internal Transcribed Spacer) sequence of P. paullula was not found in GenBank except our submission (MK949148). The pathogen was identified as P. paullula f.sp. monsterae based on morphological and molecular evidence. To our knowledge, this is the first report of P. paullula infecting M. deliciosa in north China.
  • Identification of Diplodia seriata causing black spot on branches and trunks of apple trees in Xinjiang
    ZHU Zong-cai ,ZHANG Wang-bin, YUE Juan, YI Zi-bo
    Acta Phytopathologica Sinica. 2020, 50(3): 373-376. https://doi.org/10.13926/j.cnki.apps.000325
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    In May 2018, a disease on apple trees was detected in Aksu, Xinjiang, China (41°17'18''N, 80°21'20''E;altitude:1104 m), whose typical symptoms were on the branches and the infected parts had many necrotic dark spots. There were also accompanied by browning and tissue necrosis under the bark at the center of the stem. We used a conventional method on tissue separation to isolate and purify the pathogens from diseased spe-cimens. The results showed that the fungal conidia were obtusely rounded on both ends, crescent shape, truncated base, and smooth. Conidial stems were clustered from the bottom, with asymmetric branches on each branch, and fewer branches upward, black, swollen at the base, and discrete. A multi-gene phylogenetic tree based on DNA sequences of elongation factor-1α (EF-1α, GenBank No. MK025666) and β-tubulin (GenBank No. MK033134) was built up with the collected isolates in this study, and the pathogen was determined as Diplodia seriata. To our knowledge, this is the first report on apple tree caused by D. seriata in Xinjiang, China.
  • Identification and fungicide sensitivity of pathogen causing root rot of goldthread
    CHENG Huan-huan, YANG Fang, GAO Jin, TAN De-mo, ZHANG Ming-xian, DING Hai-xia
    Acta Phytopathologica Sinica. 2020, 50(3): 377-380. https://doi.org/10.13926/j.cnki.apps.000329
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    Root rot is one of the serious diseases on goldthread (Coptis chinensis) in Shizhu County, Chongqing in recent years. The pathogen was purified and then identified based on pathogenicity test, morphological characteristics observation and multi-locus phylogenetic analyses (ITS and TEF1). And the sensitivities of the pathogen to 8 fungicides were evaluated. The results indicated that the pathogen was identified as Fusarium carminascens. Among the 8 funficides, 30% imitamine emulsion EC and 1% genazinomycin SC had the best inhibition effect with EC50 values at 0.04 and 0.06 μg·mL-1, respectively. To our knowledge, this is the first report of root rot of goldthread caused by F. carminascens in China.
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