La enfermedad mancha negra de los cítricos, causada por Guignardia citricarpa Kiely (anamorfo Phy... more La enfermedad mancha negra de los cítricos, causada por Guignardia citricarpa Kiely (anamorfo Phyllosticta citricarpa) es cuarentenaria en los principales mercados de exportación y cada vez aumentan las detecciones en destino. Por lo tanto, su diagnóstico es de gran relevancia. El objetivo fue evaluar metodología de aislamiento de hongos del género Guignardia sp.EEA Bella VistaFil: Carbajo Romero, Maria Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famailla; ArgentinaFil: Canteros, Blanca Isabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; ArgentinaFil: Meneguzzi, Natalia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famailla; Argentin
Argentinian catharanthus little leaf phytoplasma (ACLL) was found naturally infecting Daucus caro... more Argentinian catharanthus little leaf phytoplasma (ACLL) was found naturally infecting Daucus carota L. (carrot), Catharanthus roseus (LG Don) (periwinkle) and wild Matricaria chamomilla L. (chamomile). All infected plants showed symptoms of yellowing, little leaf and internodes shortening. Flower scape distortion, malformations of umbels and roots were observed in infected carrots and witches´ broom in chamomile. Only periwinkles showed virescence and phyllody. On the basis of RFLP analyses of partial 16S rDNA, ribosomal protein rpl22 and tuf (EF-Tu) genes, ACLL phytoplasma was classified in group 16SrI (‘Ca. Phytoplasma asteris’), new subgroup 16SrI-S (rr-rp) tuf-H. All ACLL phytoplasma strains have 16S rRNA interoperon sequence heterogeneity as shown by PCR-RFLP and nucleotide sequence analyses. Phylogenetic analysis using 16S rDNA sequences clustered ACLL phytoplasma strains into a new phylogenetic lineage within group 16SrI.
ABSTRACT The objective of this study was to analyze the distribution pattern of the different cau... more ABSTRACT The objective of this study was to analyze the distribution pattern of the different causes of the production of non-marketable fruit throughout the harvest season for several strawberry cultivars grown in a sub-tropical climate: ‘Carmela’, ‘Elyana’, ‘Florida Festival’, ‘Radiance’, ‘Macarena’ and ‘Candonga’. Fruit was harvested 2-3 times a week between June and October. In June, the main cause of non-marketable fruit production was fruit rot (90%). In July and August, fruit was mostly discarded because of small size (40%), or it was malformed (40%). In September and October the primary cause of non-marketable fruit was small size (65-87%). ‘Elyana’ had least discarded fruit (9 fruits/plant), while ‘Florida Festival’ had the highest rate of non-marketable fruit (18 fruits/plant); however, this cultivar had a marketable yield 31% higher than ‘Elyana’. Knowing what causes the production of non-marketable fruit in different months allows the establishment of correlations between losses and weather factors, the genotype, the phenological stage, and the physiology of the plant. Such knowledge contributes to decisión making for the implementation of crop management measures that mitigate fruit losses.
International journal of systematic and evolutionary microbiology, Jan 23, 2015
Strawberry Red Leaf phytoplasma was found in strawberry plants from production fields in Lules (T... more Strawberry Red Leaf phytoplasma was found in strawberry plants from production fields in Lules (Tucumán province) and Bella Vista (Corrientes province), Argentina. Characteristic strawberry red leaf symptoms were stunting, young leaves with yellowing at the edges, matures leaves with curling and reddish at abaxial face, flower and fruit deformation and death. The pathogen was detected with phytoplasma-universal primer pairs P1/P7 followed by R16F2n/R16R2 as nested primers in 13 diseased plants. Based on RFLP and sequence analysis of amplified 16S rDNA, the phytoplasma was related to 16SrXIII group (Mexican periwinkle virescence). In silico RFLP profile revealed the presence of a unique pattern from all the analyzed samples, showing that the novel phytoplasma is different from all phytoplasmas composing the 16SrXIII group. The phylogenetic analysis was consistent with RFLP analysis since the Strawberry Red Leaf phytoplasma was grouped within 16SrXIII group but forming a particular cl...
ABSTRACT Two phytoplasmas closely related to the X-disease group were associated with China-tree ... more ABSTRACT Two phytoplasmas closely related to the X-disease group were associated with China-tree (Melia azedarach L.) and garlic (Allium sativum L.) decline diseases in Argentina. The present work was aimed at studying their phylogenetic relationship based on molecular characterization of the 16S ribosomal DNA sequences. Phytoplasma DNAs were obtained from naturally infected China-tree and garlic plants from different geographical isolates. The results from analysis of restriction fragment length polymorphisms and nucleotide sequences of the 16S rDNA showed the affiliation of China-tree and garlic decline phytoplasmas to the 16SrIII (X-disease group), subgroups B and J, respectively. Both organisms had high sequence similarities in the 16SrDNA nucleotide sequence with the Chayote witches’ broom phytoplasma from Brazil. The phylogenetic tree, constructed by parsimony analysis, grouped the Garlic decline, China-tree decline, Chayote witches’ broom and Clover yellow edge phytoplasmas into a cluster separated from the other phytoplasmas of the X-disease group.
... China-tree (Melia azedarach L.) is a fast-growing species native to Southeast Asia (Ascher et... more ... China-tree (Melia azedarach L.) is a fast-growing species native to Southeast Asia (Ascher et al., 1995) which was widely ... province of Córdoba), San Juan (San Juan), Chilecito (La Rioja), La Merced (Catamarca), Tucumán (Tucumán), Jujuy (Jujuy), Roque Sáenz Peña and ...
International journal of systematic and evolutionary microbiology, Jan 2, 2016
Strawberry plants showing symptoms of lethal redness disease were found in production fields loca... more Strawberry plants showing symptoms of lethal redness disease were found in production fields located in Tucuman Province, Argentina. The presence of phytoplasmas was confirmed by PCR of 16Sr DNA gene using phytoplasma universal primers. According to the 16S rDNA gene sequence identity, the four isolates analyzed are related to the X-disease group (16SrIII) (identity~99%). These results were confirmed by the in silico, actual RFLP and also by phylogenetic analyses of 16S rDNA gene. This new phytoplasma was named as Strawberry X-Redness (StrawXR). The results from virtual and actual RFLP analysis of 16S rDNA gene reveal the presence of subgroup 16SrIII-J and three new 16SrIII subgroups. This is the first record of phytoplasmas from X-disease group associated to strawberry in Argentina. These results confirm the prevalence of X-disease group and also contribute to the knowledge of diversity of phytoplasmas in this region.
La enfermedad mancha negra de los cítricos, causada por Guignardia citricarpa Kiely (anamorfo Phy... more La enfermedad mancha negra de los cítricos, causada por Guignardia citricarpa Kiely (anamorfo Phyllosticta citricarpa) es cuarentenaria en los principales mercados de exportación y cada vez aumentan las detecciones en destino. Por lo tanto, su diagnóstico es de gran relevancia. El objetivo fue evaluar metodología de aislamiento de hongos del género Guignardia sp.EEA Bella VistaFil: Carbajo Romero, Maria Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famailla; ArgentinaFil: Canteros, Blanca Isabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; ArgentinaFil: Meneguzzi, Natalia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famailla; Argentin
Argentinian catharanthus little leaf phytoplasma (ACLL) was found naturally infecting Daucus caro... more Argentinian catharanthus little leaf phytoplasma (ACLL) was found naturally infecting Daucus carota L. (carrot), Catharanthus roseus (LG Don) (periwinkle) and wild Matricaria chamomilla L. (chamomile). All infected plants showed symptoms of yellowing, little leaf and internodes shortening. Flower scape distortion, malformations of umbels and roots were observed in infected carrots and witches´ broom in chamomile. Only periwinkles showed virescence and phyllody. On the basis of RFLP analyses of partial 16S rDNA, ribosomal protein rpl22 and tuf (EF-Tu) genes, ACLL phytoplasma was classified in group 16SrI (‘Ca. Phytoplasma asteris’), new subgroup 16SrI-S (rr-rp) tuf-H. All ACLL phytoplasma strains have 16S rRNA interoperon sequence heterogeneity as shown by PCR-RFLP and nucleotide sequence analyses. Phylogenetic analysis using 16S rDNA sequences clustered ACLL phytoplasma strains into a new phylogenetic lineage within group 16SrI.
ABSTRACT The objective of this study was to analyze the distribution pattern of the different cau... more ABSTRACT The objective of this study was to analyze the distribution pattern of the different causes of the production of non-marketable fruit throughout the harvest season for several strawberry cultivars grown in a sub-tropical climate: ‘Carmela’, ‘Elyana’, ‘Florida Festival’, ‘Radiance’, ‘Macarena’ and ‘Candonga’. Fruit was harvested 2-3 times a week between June and October. In June, the main cause of non-marketable fruit production was fruit rot (90%). In July and August, fruit was mostly discarded because of small size (40%), or it was malformed (40%). In September and October the primary cause of non-marketable fruit was small size (65-87%). ‘Elyana’ had least discarded fruit (9 fruits/plant), while ‘Florida Festival’ had the highest rate of non-marketable fruit (18 fruits/plant); however, this cultivar had a marketable yield 31% higher than ‘Elyana’. Knowing what causes the production of non-marketable fruit in different months allows the establishment of correlations between losses and weather factors, the genotype, the phenological stage, and the physiology of the plant. Such knowledge contributes to decisión making for the implementation of crop management measures that mitigate fruit losses.
International journal of systematic and evolutionary microbiology, Jan 23, 2015
Strawberry Red Leaf phytoplasma was found in strawberry plants from production fields in Lules (T... more Strawberry Red Leaf phytoplasma was found in strawberry plants from production fields in Lules (Tucumán province) and Bella Vista (Corrientes province), Argentina. Characteristic strawberry red leaf symptoms were stunting, young leaves with yellowing at the edges, matures leaves with curling and reddish at abaxial face, flower and fruit deformation and death. The pathogen was detected with phytoplasma-universal primer pairs P1/P7 followed by R16F2n/R16R2 as nested primers in 13 diseased plants. Based on RFLP and sequence analysis of amplified 16S rDNA, the phytoplasma was related to 16SrXIII group (Mexican periwinkle virescence). In silico RFLP profile revealed the presence of a unique pattern from all the analyzed samples, showing that the novel phytoplasma is different from all phytoplasmas composing the 16SrXIII group. The phylogenetic analysis was consistent with RFLP analysis since the Strawberry Red Leaf phytoplasma was grouped within 16SrXIII group but forming a particular cl...
ABSTRACT Two phytoplasmas closely related to the X-disease group were associated with China-tree ... more ABSTRACT Two phytoplasmas closely related to the X-disease group were associated with China-tree (Melia azedarach L.) and garlic (Allium sativum L.) decline diseases in Argentina. The present work was aimed at studying their phylogenetic relationship based on molecular characterization of the 16S ribosomal DNA sequences. Phytoplasma DNAs were obtained from naturally infected China-tree and garlic plants from different geographical isolates. The results from analysis of restriction fragment length polymorphisms and nucleotide sequences of the 16S rDNA showed the affiliation of China-tree and garlic decline phytoplasmas to the 16SrIII (X-disease group), subgroups B and J, respectively. Both organisms had high sequence similarities in the 16SrDNA nucleotide sequence with the Chayote witches’ broom phytoplasma from Brazil. The phylogenetic tree, constructed by parsimony analysis, grouped the Garlic decline, China-tree decline, Chayote witches’ broom and Clover yellow edge phytoplasmas into a cluster separated from the other phytoplasmas of the X-disease group.
... China-tree (Melia azedarach L.) is a fast-growing species native to Southeast Asia (Ascher et... more ... China-tree (Melia azedarach L.) is a fast-growing species native to Southeast Asia (Ascher et al., 1995) which was widely ... province of Córdoba), San Juan (San Juan), Chilecito (La Rioja), La Merced (Catamarca), Tucumán (Tucumán), Jujuy (Jujuy), Roque Sáenz Peña and ...
International journal of systematic and evolutionary microbiology, Jan 2, 2016
Strawberry plants showing symptoms of lethal redness disease were found in production fields loca... more Strawberry plants showing symptoms of lethal redness disease were found in production fields located in Tucuman Province, Argentina. The presence of phytoplasmas was confirmed by PCR of 16Sr DNA gene using phytoplasma universal primers. According to the 16S rDNA gene sequence identity, the four isolates analyzed are related to the X-disease group (16SrIII) (identity~99%). These results were confirmed by the in silico, actual RFLP and also by phylogenetic analyses of 16S rDNA gene. This new phytoplasma was named as Strawberry X-Redness (StrawXR). The results from virtual and actual RFLP analysis of 16S rDNA gene reveal the presence of subgroup 16SrIII-J and three new 16SrIII subgroups. This is the first record of phytoplasmas from X-disease group associated to strawberry in Argentina. These results confirm the prevalence of X-disease group and also contribute to the knowledge of diversity of phytoplasmas in this region.
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