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Assunta Bertaccini - One of the best experts on this subject based on the ideXlab platform.
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Detection and characterisation of phytoplasma strains associated with field bindweed Witches’ Broom disease in Iran
2019Co-Authors: Mohammad Salehi, Seyyed Alireza Esmailzadeh Hosseini, Elham Salehi, Assunta BertacciniAbstract:During 2013–2015 surveys in Fars, Lorestan and Yazd provinces (Iran), a field bindweed Witches’ Broom (FBWB) disease was observed. The main symptoms were reduction of leaves size, yellowing, internode shortening, Witches’ Broom and stunting. The agent of FBWB was dodder transmitted to periwinkle plants inducing phytoplasma-type symptoms. Amplifications of nearly 1.8 and 1.2 kbp were, respectively, obtained from 15 symptomatic bindweed plants and 28 symptomatic dodder-inoculated periwinkles. Virtual RFLP analyses showed that the phytoplasma detected belonged to 16SrXII-A subgroup, and it was the same in all the samples examined; phylogenetic analyses confirmed it as a ‘Candidatus Phytoplasma solani’-related strain. This is the first report of 16SrXII-A phytoplasmas presence in bindweed plants showing Witches’ Broom symptoms in Fars, Lorestan and Yazd provinces. As a perennial widespread weed, it may act as a 16SrXII-A phytoplasma source for alfalfa, grapevine, Sophora alopecuroides, tomato, hemp and Japanese spindle reported diseases in these Iranian provinces.
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detection and characterisation of phytoplasma strains associated with field bindweed Witches Broom disease in iran
Archives of Phytopathology and Plant Protection, 2018Co-Authors: Mohammad Salehi, Seyyed Alireza Esmailzadeh Hosseini, Elham Salehi, Assunta BertacciniAbstract:During 2013–2015 surveys in Fars, Lorestan and Yazd provinces (Iran), a field bindweed Witches’ Broom (FBWB) disease was observed. The main symptoms were reduction of leaves size, yellowing, intern...
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comparative transcriptome analysis of ziziphus jujuba infected by jujube Witches Broom phytoplasmas
Scientia Horticulturae, 2017Co-Authors: Xinping Fan, Wei Liu, Yongsheng Qiao, Yongjin Shang, Guoping Wang, Xin Tian, Yuanhuai Han, Assunta BertacciniAbstract:Abstract Ziziphus jujuba is one of the most important and widely grown fruits in China. Jujube Witches' Broom (JWB), an important disease in Z. jujube, could cause heavy loss for its industry. The disease is associated with the presence of ‘Candidatus Phytoplasma ziziphi’, a prokaryote, and very little knowledge is known about its interactions with jujube plants. Therefore, in the present study cDNA samples from healthy and diseased plants were sequenced on Illumina HISeq2000 and gene expression and metabolism regulation were compared. In the two libraries obtained from the leaves, 4266 differentially expressed genes (DEGs) were identified. Among them, 2070 genes were upregulated, and 2196 genes were downregulated. The comparison between the libraries from flowers showed 3800 DEGs, with 1965 upregulated and 1835 down-regulated genes. Among all these some specific genes were identified to be functionally related to the amino acid metabolism and the carotenoid pathway, which may be related to the lack of nutrition and the main symptoms of yellowing, Brooming and small leaves. The results of this work provides a valuable resource for further studies of the disease on genetic and molecular levels.
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association of eriophyes dimocarpi acari eriophyidae with longan Witches Broom disease in vietnam
Archives of Phytopathology and Plant Protection, 2017Co-Authors: Trinh Xuan Hoat, Mai Van Quan, La Van Hao, Tran Thi Chi, Dang Thi Lan Anh, Pham Van Son, Nguyen Nhu Cuong, Assunta BertacciniAbstract:AbstractLongan Witches’ Broom (LgWB) syndrome was observed in all longan-growing provinces of Vietnam. Key symptoms include: small, stunted shoots with curved, rolled up margins, deformed leaves with blisters and hairy patches on the underside; abnormal development of flower structures, flower abortion, failure to produce fruits or developing small fruits. During 2012–2015, field surveys and study of the relationship between LgWB symptoms and Eriophyes dimocarpi mites presence were carried out. Moreover, molecular analysis, electron microscopy observations, E. dimocarpi inoculations, pruning of affected spikelets and miticide experiments were performed. An average of 36.58% of longan seedlings inoculated with E. dimocarpi mites showed typical symptoms of LgWB at about 27.5 days after inoculation. The use of several pesticides in different combinations showed high efficacy on E. dimocarpi mites elimination and of symptomatology incidence reduction. These results suggest a significant association of E. dimo...
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population genetic analysis reveals a low level of genetic diversity of candidatus phytoplasma aurantifolia causing Witches Broom disease in lime
SpringerPlus, 2016Co-Authors: Shaikha Y Alabadi, Abdullah M Alsadi, Matthew Dickinson, M S Alhammadi, R M Alshariqi, Rashid Alyahyai, Elham A Kazerooni, Assunta BertacciniAbstract:Witches’ Broom disease of lime (WBDL) is a serious phytoplasma disease of acid lime in Oman, the UAE and Iran. Despite efforts to study it, no systemic study attempted to characterize the relationship among the associated phytoplasma, ‘Candidatus Phytoplasma aurantifolia’, from the three countries. This study utilized sequences of the 16S rRNA, imp and secA genes to characterize 57 strains collected from Oman (38), the UAE (9) and Iran (10). Phylogenetic analysis based on the 16S rRNA gene showed that the 57 strains shared 98.5–100 % nucleotide similarity to each other and to strains of ‘Ca. P. aurantifolia’ available in GenBank. The level of genetic diversity was low based on the 16S rRNA (0-0.011), imp (0–0.002) and secA genes (0–0.015). The presence of low level of diversity among phytoplasma strains from Oman, the UAE and Iran can be explained by the movement of infected lime seedlings from one country to another through trading and exchange of infected plants. The study discusses implication of the findings on WBDL spread and management.
R. E. Davis - One of the best experts on this subject based on the ideXlab platform.
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candidatus phytoplasma luffae a novel taxon associated with Witches Broom disease of loofah luffa aegyptica mill
International Journal of Systematic and Evolutionary Microbiology, 2017Co-Authors: R. E. Davis, Ellen L Dally, Yan Zhao, Wei Wei, Ingming LeeAbstract:The phytoplasma associated with Witches’ Broom disease of loofah [Luffa aegyptica Mill., syn. Luffa cylindrica (L.) M.J. Roem.] in Taiwan was classified in group 16SrVIII, subgroup A (16SrVIII-A), based on results from actual and in silico RFLP analysis of 16S rRNA gene sequences. Nucleotide sequencing of PCR-amplified, cloned DNA segments revealed rrn interoperon sequence heterogeneity in the loofah Witches’ Broom (LfWB) phytoplasma. Whereas the 16S–23S rRNA spacer region of rrnA contained a complete tRNA-Ile gene, the spacer of rrnB contained a nonfunctional remnant of a tRNA gene. Phylogenetic analysis of the rrnA and rrnB 16S rRNA genes revealed that the LfWB phytoplasma represented a distinct lineage within the phytoplasma clade, and the LfWB phytoplasma shared less than 97.5 % nucleotide sequence similarity of 16S rRNA genes with previously described ‘Candidatus Phytoplasma ’ taxa. Based on unique properties of DNA, we propose recognition of loofah Witches’ Broom phytoplasma strain LfWBR as representative of a novel taxon, ‘Candidatus Phytoplasma luffae’.
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differentiation and classification of phytoplasmas in the pigeon pea Witches Broom group 16srix an update based on multiple gene sequence analysis
International Journal of Systematic and Evolutionary Microbiology, 2012Co-Authors: I M Lee, Assunta Bertaccini, Yan Zhao, Kristi D Bottnerparker, R. E. DavisAbstract:The pigeon pea Witches’-Broom phytoplasma group (16SrIX) comprises diverse strains that cause numerous diseases in leguminous trees and herbaceous crops, vegetables, a fruit, a nut tree and a forest tree. At least 14 strains have been reported worldwide. Comparative phylogenetic analyses of the highly conserved 16S rRNA gene and the moderately conserved rplV (rpl22)–rpsC (rps3) and secY genes indicated that the 16SrIX group consists of at least six distinct genetic lineages. Some of these lineages cannot be readily differentiated based on analysis of 16S rRNA gene sequences alone. The relative genetic distances among these closely related lineages were better assessed by including more variable genes [e.g. ribosomal protein (rp) and secY genes]. The present study demonstrated that virtual RFLP analyses using rp and secY gene sequences allowed unambiguous identification of such lineages. A coding system is proposed to designate each distinct rp and secY subgroup in the 16SrIX group.
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candidatus phytoplasma tamaricis a novel taxon discovered in Witches Broom diseased salt cedar tamarix chinensis lour
International Journal of Systematic and Evolutionary Microbiology, 2009Co-Authors: Yan Zhao, R. E. Davis, Wei Wei, Qingrong Sun, Qingzhong LiuAbstract:Salt cedar trees with pronounced Witches'-Broom symptoms were observed in their natural habitat in China. 16S rRNA gene sequences unique to phytoplasmas were detected in every DNA sample extracted from stem and leaf tissues of the symptomatic trees, revealing a direct association between phytoplasma infection and the salt cedar Witches'-Broom (SCWB) disease. Phylogenetic analysis of the SCWB phytoplasma 16S rRNA gene sequence indicated that the SCWB phytoplasma belonged to a subclade consisting of several mutually distinct 'Candidatus Phytoplasma' taxa including 'Ca. Phytoplasma prunorum', 'Ca. Phytoplasma mali', 'Ca. Phytoplasma pyri' and 'Ca. Phytoplasma spartii'. Pairwise sequence similarity scores calculated from an alignment of near full-length 16S rRNA genes revealed that SCWB phytoplasma shared 96.6 % or less sequence similarity with each previously described or proposed 'Ca. Phytoplasma' taxon, justifying the recognition of SCWB phytoplasma as a novel taxon, 'Candidatus Phytoplasma tamaricis'. The distinct virtual RFLP pattern derived from the SCWB phytoplasma 16S rRNA gene sequence, together with its lower-than-threshold similarity coefficient values with RFLP patterns of any of the 29 previously established groups, supported the recognition of a new 16Sr group, designated 16SrXXX, salt cedar Witches'-Broom phytoplasma group.
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genetic diversity among phytoplasmas infecting opuntia species virtual rflp analysis identifies new subgroups in the peanut Witches Broom phytoplasma group
International Journal of Systematic and Evolutionary Microbiology, 2008Co-Authors: R. E. Davis, Hairu Chen, Y. ZhaoAbstract:Phytoplasmas were detected in cactus (Opuntia species) plants exhibiting Witches'-Broom disease symptoms in Yunnan Province, south-western China. Comparative and phylogenetic analyses of 16S rRNA gene sequences indicated that an overwhelming majority of the cactus-infecting phytoplasmas under study belonged to the peanut Witches'-Broom phytoplasma group (16SrII). Genotyping through use of computer-simulated restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes revealed a remarkable genetic diversity among these cactus-infecting phytoplasma strains. Based on calculated coefficients of RFLP pattern similarities, seven new 16SrII subgroups were recognized, bringing the total of described group 16SrII subgroups to 12 worldwide. Geographical areas differed from one another in the extent of genetic diversity among cactus-infecting phytoplasma strains. The findings have implications for relationships between ecosystem distribution and the emergence of group 16SrII subgroup diversity.
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first report of Witches Broom disease in a cannabis spp in china and its association with a phytoplasma of elm yellows group 16srv
Plant Disease, 2007Co-Authors: Yan Zhao, R. E. Davis, Ingming Lee, Q Sun, Q LiuAbstract:Hemp fiber plants (Cannabis spp.) spread naturally in almost every climate zone in China and have a long history of cultivation in the country (1). While hemp stalks provide high-quality fibers for making ropes, clothes, and paper products, hemp seeds are a rich source of edible oil. During the summer of 2004, a disease characterized by Witches'-Broom symptoms was observed in wild hemp fiber plants growing in suburban Taian, Shandong, China. The diseased plants developed clusters of highly proliferating branches with much shortened internodes and leaves on the affected branches were significantly reduced in size. Phytoplasma infection was suspected in this hemp fiber Witches'-Broom (HFWB) disease because of the typical symptoms and because of its geographic location where other phytoplasmal diseases such as jujube Witches'-Broom (JWB), paulownia Witches'-Broom (PaWB), paper mulberry Witches'-Broom (PMWB), and Chinese wingnut Witches'-Broom (CWWB) diseases were previously reported (3,4). Total DNA was extracted from leaves of four diseased and four nearby healthy looking hemp fiber plants. Nested PCR were carried out on the DNA samples using phytoplasma universal 16S rDNA primers (P1A/16S-SR and R16F2n/R16R2) (2). Results revealed that all examined diseased plants were infected by phytoplasma, whereas nearby healthy looking plants were phytoplasma free. Subsequent restriction fragment length polymorphism (RFLP) analysis of the PCR-amplified 1.25-kb 16S rDNA R16F2n/R16R2 fragment indicated that the phytoplasma associated with HFWB disease belongs to subgroup 16SrV-B of the elm yellows (EY) phytoplasma group. Nucleotide sequence analysis of the cloned HFWB phytoplasma partial rRNA operon (GenBank Accession No. EF029092), spanning a near full-length 16S rRNA gene and a partial 16S-23S rRNA intergenic spacer, suggested that HFWB phytoplasma is most closely related to JWB and PMWB phytoplasmas, both members of subgroup16SrV-B. To further characterize the HFWB phytoplasma, a genomic segment covering full-length ribosomal protein genes rplV and rpsC was PCR-amplified using primer pair rp(V)F1A/rp(V)R1A (2), cloned, and sequenced (GenBank Accession No. EF029093). The nucleotide sequence of the HFWB phytoplasma rplV and rpsC locus is nearly identical (99.9%) to that of JWB phytoplasma. To our knowledge, this is the first report of a phytoplasmal disease in Cannabis spp. Since HFWB and JWB phytoplasmas share extremely high sequence identity and share the same eco-geographic location, further investigation is warranted to determine whether these two phytoplasmas are actually one species that can infect both plants, an issue having important implications in managing both diseases. References: (1) S. Hong and R. C. Clarke. J. Int. Hemp Assoc. 3:55, 1996. (2) I. M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (3) Q. Liu et al. Plant Dis. 88:770, 2004. (4) Q. Liu et al. Plant Dis. 89:529, 2005.
Shigetou Namba - One of the best experts on this subject based on the ideXlab platform.
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candidatus phytoplasma balanitae associated with Witches Broom disease of balanites triflora
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Nang Kyu Kyu Win, Assunta Bertaccini, Shigetou Namba, Seungyeol Lee, Heeyoung JungAbstract:A phytoplasma was identified in naturally infected wild Balanites triflora plants exhibiting typical Witches' Broom symptoms (Balanites Witches' Broom: BltWB) in Myanmar. The 16S rRNA gene sequence revealed that BltWB phytoplasma had the highest similarity to that of 'Candidatus Phytoplasma ziziphi' and it was also closely related to that of 'Candidatus Phytoplasma ulmi'. Phylogenetic analysis of the 16S rRNA gene sequences indicated that the BltWB phytoplasma clustered as a discrete subclade with Elm yellows phytoplasmas. RFLP analysis of the 16S rRNA gene including the 16S-23S spacer region differentiated the BltWB phytoplasma from 'Ca. P. ziziphi', 'Ca. P. ulmi' and 'Candidatus Phytoplasma trifolii'. Analysis of additional ribosomal protein (rp) and translocase protein (secY) gene sequences and phylogenetic analysis of BltWB showed that this phytoplasma was clearly distinguished from those of other 'Candidatus Phytoplasma' taxa. Taking into consideration the unique plant host and the restricted geographical occurrence in addition to the 16S rRNA gene sequence similarity, the BltWB phytoplasma is proposed to represent a novel taxon, 'Candidatus Phytoplasma balanitae'.
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movement of onion yellows phytoplasma and cryptotaenia japonica Witches Broom phytoplasma in the nonvector insect nephotettix cincticeps
Japanese Journal of Phytopathology, 2009Co-Authors: S. Nakajima, Shigetou Namba, Norio Nishimura, I. Fujisawa, Young H J Jung, S Kakizawa, Tsuneo TsuchizakiAbstract:Two strains of ‘Candidatus Phytoplasma asteris’ (onion yellows phytoplasma: OYP and Cryptotaenia japonica Witches’ Broom phytoplasma: CJWP) were detected by PCR from the nonvector leafhopper (Nephotettix cincticeps) that had fed on phytoplasma-infected plants or had been injected with one of the phytoplasmas. In all experiments, each phytoplasma was detected from the mid-gut, abdomen, thorax, head and salivary glands of insects after acquisition feeding or injection. However, neither phytoplasma was transmitted after inoculation feeding. This report is the first that phytoplasmas can pass through the mid-gut wall and reach the salivary glands of a nonvector leafhopper that had fed on phytoplasma-infected plants.
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candidatus phytoplasma ziziphi a novel phytoplasma taxon associated with jujube Witches Broom disease
International Journal of Systematic and Evolutionary Microbiology, 2003Co-Authors: Heeyoung Jung, T Sawayanagi, Shigeyuki Kakizawa, Hisashi Nishigawa, Shinichi Miyata, Kenro Oshima, Masashi Ugaki, Tadaaki Hibi, Shigetou NambaAbstract:Phylogenetic relationships of five jujube Witches'-Broom (JWB) phytoplasma isolates from four different districts, and other phytoplasmas, were investigated by 16S rDNA PCR amplification and sequence analysis. The 16S rDNA sequences of any pair of the five isolates of JWB phytoplasmas were >99·5 % similar. The JWB phytoplasma 16S rDNA sequences were most closely related to that of the elm yellows (EY) phytoplasma in 16S-group VIII. Phylogenetic analysis of the 16S rDNA sequences from the JWB phytoplasma isolates, together with sequences from most of the phytoplasmas archived in GenBank, produced a tree in which the JWB isolates clustered as a discrete subgroup. The uniqueness of the JWB phytoplasma appears to be correlated with a specific insect vector (Hishimonus sellatus) and the host plant (Zizyphus jujuba), or with a specific geographical distribution. The unique properties of the JWB phytoplasma sequences clearly indicate that it represents a novel taxon, ‘Candidatus Phytoplasma ziziphi’.
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aster yellows subgroup candidatus phytoplasma sp ay 16s group ay sg phytoplasma associated with porcelain vine showing Witches Broom symptoms in south korea
Journal of General Plant Pathology, 2003Co-Authors: Heeyoung Jung, Tadaaki Hibi, Michi Yae, Joontak Lee, Shigetou NambaAbstract:This is the first report of a phytoplasma in porcelain vine [Ampelopsis brevipedunculata var. heterophylla (Thunb.) Hara.] with severe Witches' Broom symptoms in Korea. On the basis of the polymerase chain reaction-amplified ribosomal DNA, the phytoplasma infecting porcelain vine was classified as a member of the aster yellows subgroup.
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characterization of a phytoplasma associated with Witches Broom disease of potatoes in korea
Journal of General Plant Pathology, 2003Co-Authors: Heeyoung Jung, Tadaaki Hibi, Joontak Lee, Youngil Hahm, Shigetou NambaAbstract:Symptoms of Witches' Broom disease caused by phytoplasma, including general stunting and yellowing, were observed in potatoes (Solanum tuberosum L.) in a storehouse on Jeju Island, Korea in 1998. Based on sequence analysis of DNA products from polymerase chain reaction (PCR)-amplified 16S ribosomal DNA and 16S–23S spacer region using universal phytoplasma primers, the phytoplasma associated with potato Witches' Broom disease (PWB) was identified as a member of 16S-group VIII. It was most closely related to elm AH phytoplasma (99.7% similarity, accession no. AF268895), which is in the clover proliferation (CP) subgroup. This report is the first from the East Asian continent of a plant pathogenic phytoplasma belonging to the CP subgroup and includes the nucleotide sequence of most of the potato phytoplasma 16S rDNA.
Heeyoung Jung - One of the best experts on this subject based on the ideXlab platform.
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candidatus phytoplasma balanitae associated with Witches Broom disease of balanites triflora
International Journal of Systematic and Evolutionary Microbiology, 2013Co-Authors: Nang Kyu Kyu Win, Assunta Bertaccini, Shigetou Namba, Seungyeol Lee, Heeyoung JungAbstract:A phytoplasma was identified in naturally infected wild Balanites triflora plants exhibiting typical Witches' Broom symptoms (Balanites Witches' Broom: BltWB) in Myanmar. The 16S rRNA gene sequence revealed that BltWB phytoplasma had the highest similarity to that of 'Candidatus Phytoplasma ziziphi' and it was also closely related to that of 'Candidatus Phytoplasma ulmi'. Phylogenetic analysis of the 16S rRNA gene sequences indicated that the BltWB phytoplasma clustered as a discrete subclade with Elm yellows phytoplasmas. RFLP analysis of the 16S rRNA gene including the 16S-23S spacer region differentiated the BltWB phytoplasma from 'Ca. P. ziziphi', 'Ca. P. ulmi' and 'Candidatus Phytoplasma trifolii'. Analysis of additional ribosomal protein (rp) and translocase protein (secY) gene sequences and phylogenetic analysis of BltWB showed that this phytoplasma was clearly distinguished from those of other 'Candidatus Phytoplasma' taxa. Taking into consideration the unique plant host and the restricted geographical occurrence in addition to the 16S rRNA gene sequence similarity, the BltWB phytoplasma is proposed to represent a novel taxon, 'Candidatus Phytoplasma balanitae'.
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candidatus phytoplasma ziziphi a novel phytoplasma taxon associated with jujube Witches Broom disease
International Journal of Systematic and Evolutionary Microbiology, 2003Co-Authors: Heeyoung Jung, T Sawayanagi, Shigeyuki Kakizawa, Hisashi Nishigawa, Shinichi Miyata, Kenro Oshima, Masashi Ugaki, Tadaaki Hibi, Shigetou NambaAbstract:Phylogenetic relationships of five jujube Witches'-Broom (JWB) phytoplasma isolates from four different districts, and other phytoplasmas, were investigated by 16S rDNA PCR amplification and sequence analysis. The 16S rDNA sequences of any pair of the five isolates of JWB phytoplasmas were >99·5 % similar. The JWB phytoplasma 16S rDNA sequences were most closely related to that of the elm yellows (EY) phytoplasma in 16S-group VIII. Phylogenetic analysis of the 16S rDNA sequences from the JWB phytoplasma isolates, together with sequences from most of the phytoplasmas archived in GenBank, produced a tree in which the JWB isolates clustered as a discrete subgroup. The uniqueness of the JWB phytoplasma appears to be correlated with a specific insect vector (Hishimonus sellatus) and the host plant (Zizyphus jujuba), or with a specific geographical distribution. The unique properties of the JWB phytoplasma sequences clearly indicate that it represents a novel taxon, ‘Candidatus Phytoplasma ziziphi’.
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aster yellows subgroup candidatus phytoplasma sp ay 16s group ay sg phytoplasma associated with porcelain vine showing Witches Broom symptoms in south korea
Journal of General Plant Pathology, 2003Co-Authors: Heeyoung Jung, Tadaaki Hibi, Michi Yae, Joontak Lee, Shigetou NambaAbstract:This is the first report of a phytoplasma in porcelain vine [Ampelopsis brevipedunculata var. heterophylla (Thunb.) Hara.] with severe Witches' Broom symptoms in Korea. On the basis of the polymerase chain reaction-amplified ribosomal DNA, the phytoplasma infecting porcelain vine was classified as a member of the aster yellows subgroup.
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characterization of a phytoplasma associated with Witches Broom disease of potatoes in korea
Journal of General Plant Pathology, 2003Co-Authors: Heeyoung Jung, Tadaaki Hibi, Joontak Lee, Youngil Hahm, Shigetou NambaAbstract:Symptoms of Witches' Broom disease caused by phytoplasma, including general stunting and yellowing, were observed in potatoes (Solanum tuberosum L.) in a storehouse on Jeju Island, Korea in 1998. Based on sequence analysis of DNA products from polymerase chain reaction (PCR)-amplified 16S ribosomal DNA and 16S–23S spacer region using universal phytoplasma primers, the phytoplasma associated with potato Witches' Broom disease (PWB) was identified as a member of 16S-group VIII. It was most closely related to elm AH phytoplasma (99.7% similarity, accession no. AF268895), which is in the clover proliferation (CP) subgroup. This report is the first from the East Asian continent of a plant pathogenic phytoplasma belonging to the CP subgroup and includes the nucleotide sequence of most of the potato phytoplasma 16S rDNA.
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candidatus phytoplasma castaneae a novel phytoplasma taxon associated with chestnut Witches Broom disease
International Journal of Systematic and Evolutionary Microbiology, 2002Co-Authors: Heeyoung Jung, T Sawayanagi, Shigeyuki Kakizawa, Hisashi Nishigawa, Shinichi Miyata, Kenro Oshima, Masashi Ugaki, Tadaaki Hibi, Shigetou NambaAbstract:In Korea, Japanese chestnut trees (Castanea crenata Sieb. and Zucc.) showing symptoms indicative of Witches' Broom disease, including abnormally small leaves and yellowing of young leaves, were examined. Since the symptoms were suggestive of a phytoplasma infection, tissues were assayed for phytoplasmas by PCR analysis using a pair of universal primers that amplify a 1.4-kbp phytoplasma 16S rDNA fragment. The phytoplasma-specific fragment was amplified from diseased plants, but not from healthy plants, indicating that a phytoplasma was the causal agent of the chestnut Witches' Broom (CnWB) disease. The phylogenetic relationship of the CnWB phytoplasma to other phytoplasmas was examined by sequence analysis of the 16S rDNA. A phylogenetic analysis of 16S rDNA sequences of the phytoplasmas placed the CnWB phytoplasma within a distinct subgroup in the phytoplasma clade of the class Mollicutes. The phylogenetic tree indicated that the CnWB phytoplasma is related most closely to coconut phytoplasmas and suggested that they share a common ancestor. The unique properties of the CnWB phytoplasma sequences clearly establish that it represents a novel taxon, 'Candidatus Phytoplasma castaneae'.
Carlos Priminho Pirovani - One of the best experts on this subject based on the ideXlab platform.
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The selenium-binding protein of Theobroma cacao: A thermostable protein involved in the Witches’ Broom disease resistance
Plant physiology and biochemistry : PPB, 2019Co-Authors: Akyla Maria Martins Alves, Karina Peres Gramacho, Carlos Priminho Pirovani, Sara Pereira Menezes, Eline Matos Lima, Bruno Silva Andrade, Monaliza Macêdo Ferreira, Fabienne MicheliAbstract:The selenium-binding proteins are known to be inducers of apoptosis in human and animals, and have been studied as target for the treatment of various types of cancer. In plants, SBP expression has been related to abiotic and biotic stress resistance. The SBP from Theobroma cacao (TcSBP) was first identified from a cocoa-Moniliophthora perniciosa cDNA library. The present study provides details on the TcSBP gene and protein structure. Multiple alignments revealed conserved domains between SBP from plants, human and archea. Homology modeling and molecular docking were performed and showed that the TcSBP has affinity to selenite in the active CSSC site. This result was confirmed by circular dichroism of the recombinant TcSBP, which also presented thermostable behavior. RT-qPCR analysis showed that TcSBP was differentially expressed in resistant vs susceptible cacao varieties inoculated by M. perniciosa and its expression was probably due to hormone induction via cis-regulating elements present in its promotor. The presence of the CSSC domain suggested that TcSBP acted by altering oxidation/reduction of proteins during H2O2 production and programmed cell death in the final stages of the Witches' Broom disease. To our knowledge, this is the first in silico and in vitro analysis of the SBP from cacao.
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cacao phylloplane the first battlefield against moniliophthora perniciosa which causes Witches Broom disease
Phytopathology, 2017Co-Authors: D S M Almeida, Thyago Hermylly Santana Cardoso, Fabienne Micheli, Karina Peres Gramacho, Fátima Cerqueira Alvim, Carlos Priminho PirovaniAbstract:The phylloplane is the first contact surface between Theobroma cacao and the fungus Moniliophthora perniciosa, which causes Witches’ Broom disease (WBD). We evaluated the index of short glandular trichomes (SGT) in the cacao phylloplane and the effect of irrigation on the disease index of cacao genotypes with or without resistance to WBD, and identified proteins present in the phylloplane. The resistant genotype CCN51 and susceptible Catongo presented a mean index of 1,600 and 700 SGT cm−2, respectively. The disease index in plants under drip irrigation was reduced by approximately 30% compared with plants under sprinkler irrigation prior to inoculation. Leaf water wash (LWW) of the cacao inhibited the germination of spores by up to 98%. Proteins from the LWW of CCN51 were analyzed by two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by tandem mass spectrometry. The gel showed 71 spots and identified a total of 42 proteins (28 from the plant and 14 from bacteria). Proteins...
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cacao phylloplane the first battlefield against moniliophthora perniciosa which causes Witches Broom disease
Phytopathology, 2017Co-Authors: D S M Almeida, Thyago Hermylly Santana Cardoso, Fabienne Micheli, Karina Peres Gramacho, Fátima Cerqueira Alvim, Carlos Priminho PirovaniAbstract:The phylloplane is the first contact surface between Theobroma cacao and the fungus Moniliophthora perniciosa, which causes Witches' Broom disease (WBD). We evaluated the index of short glandular trichomes (SGT) in the cacao phylloplane and the effect of irrigation on the disease index of cacao genotypes with or without resistance to WBD, and identified proteins present in the phylloplane. The resistant genotype CCN51 and susceptible Catongo presented a mean index of 1,600 and 700 SGT cm-2, respectively. The disease index in plants under drip irrigation was reduced by approximately 30% compared with plants under sprinkler irrigation prior to inoculation. Leaf water wash (LWW) of the cacao inhibited the germination of spores by up to 98%. Proteins from the LWW of CCN51 were analyzed by two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by tandem mass spectrometry. The gel showed 71 spots and identified a total of 42 proteins (28 from the plant and 14 from bacteria). Proteins related to defense and synthesis of defense metabolites and involved in nucleic acid metabolism were identified. The results support the hypothesis that the proteins and water-soluble compounds secreted to the cacao phylloplane participate in the defense against pathogens. They also suggest that SGT can contribute to the resistance of cacao.
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Genetic and biological diversity of Trichoderma stromaticum a mycoparasite of the cacao Witches' -Broom pathogen
Phytopathology, 2006Co-Authors: Jorge Teodoro De Souza, Carlos Priminho Pirovani, Alan W V Pomella, John H. Bowers, Leandro Lopes Loguercio, K. Prakash HebbarAbstract:de Souza, J. T., Pomella, A. W. V., Bowers, J. H., Pirovani, C. P., Loguercio, L. L., and Hebbar, K. P. 2006. Genetic and biological diversity of Trichoderma stromaticum, a mycoparasite of the cacao Witches’-Broom pathogen. Phytopathology 96:61-67. The Witches’-Broom disease, caused by the basidiomycete Crinipellis perniciosa, is the most limiting factor for cacao cultivation in Brazil. Trichoderma stromaticum is a mycoparasite of the Witches’-Broom pathogen of cacao that is currently being applied in the field to manage the disease in Bahia State, Brazil. In this work, molecular and traditional methods were used to study the genetic and biological diversity of this mycoparasite. Ninety-one isolates, mostly collected from farms not sprayed with the fungus, were analyzed by amplified fragment length polymorphisms (AFLP), which showed that two genetic groups (I and II) of T. stromaticum occur in Bahia State. This classification of T. stromaticum into two distinct AFLP groups was also in agreement with several other characteristics, including growth on agar media at different temperatures and sporulation on infected stem segments (Broom pieces) and rice grains. Group II favors higher temperatures compared with group I. The genetic and biological differences of the isolates, however, were not evident in field experiments, where sporulation was evaluated on the surface of Brooms under natural conditions. Our results show that there is considerable genetic and biological diversity within T. stromaticum in Bahia and other cacao-growing regions of South America that are affected by the Witches’-Broom disease. This diversity could be explored in the development of efficient biological control agents against the disease. Factors that may affect the application and performance of this biocontrol agent in the field, such as sporulation on rice substrate and on the Brooms and growth at various temperatures, are discussed.
