cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14279247
title: Pathogenicity and characterization of Thielaviopsis ethacetica in oil palm

description: ABSTRACT Thielaviopsis paradoxa is a soilborne fungal pathogen widely distributed worldwide and capable of infecting a wide range of hosts. In oil palm, it is the etiological agent of basal rot, an important disease that can cause serious damage due to its severity and the rapid dispersion of the pathogen. This study evaluated the pathogenicity and characterized an isolate of Thielaviopsis sp. in oil palm. The isolate was obtained from the stem of an oil palm plant with apparent rot symptoms. Pathogenicity was evaluated in two oil palm cultivars, the interspecific hybrid Manicoré and the intraspecific hybrid Tenera. Seedlings were inoculated by conidial suspension at 1x107 conidia per milliliter e mycelial disks, with and without injuries in the leaf rachis. The isolate was grown in PDA culture medium for morphological characterization. Phylogenetic analysis was performed based on comparison of sequences from the EF-1? and ITS regions with sequences available from GenBank-NCBI and analyzed in Mega 6.0. The isolate was pathogenic to the two oil palm cultivars in previously injured seedlings, causing symptoms of brown rot and formation of a yellowish halo in the rachis. As the disease progressed, the leaves showed yellow coloration and dried, resulting in broken rachis. The isolate of Thielaviopsis sp. showed rapid growth with mycelial growth rate of 50.76 mm day-1, covering the 90-mm Petri plate within two days. The colony, initially white, became black with sporulation and produced two types of conidia: endoconidia and aleuroconidia. After phylogenetic analyses, the species Thielaviopsis ethacetica could be proven as the etiological agent of the dry basal rot of oil palm and could be distinguished from T. paradoxa.
DOI: 10.6084/m9.figshare.14279247.v1
title: Pathogenicity and characterization of Thielaviopsis ethacetica in oil palm

description: ABSTRACT Thielaviopsis paradoxa is a soilborne fungal pathogen widely distributed worldwide and capable of infecting a wide range of hosts. In oil palm, it is the etiological agent of basal rot, an important disease that can cause serious damage due to its severity and the rapid dispersion of the pathogen. This study evaluated the pathogenicity and characterized an isolate of Thielaviopsis sp. in oil palm. The isolate was obtained from the stem of an oil palm plant with apparent rot symptoms. Pathogenicity was evaluated in two oil palm cultivars, the interspecific hybrid Manicoré and the intraspecific hybrid Tenera. Seedlings were inoculated by conidial suspension at 1x107 conidia per milliliter e mycelial disks, with and without injuries in the leaf rachis. The isolate was grown in PDA culture medium for morphological characterization. Phylogenetic analysis was performed based on comparison of sequences from the EF-1? and ITS regions with sequences available from GenBank-NCBI and analyzed in Mega 6.0. The isolate was pathogenic to the two oil palm cultivars in previously injured seedlings, causing symptoms of brown rot and formation of a yellowish halo in the rachis. As the disease progressed, the leaves showed yellow coloration and dried, resulting in broken rachis. The isolate of Thielaviopsis sp. showed rapid growth with mycelial growth rate of 50.76 mm day-1, covering the 90-mm Petri plate within two days. The colony, initially white, became black with sporulation and produced two types of conidia: endoconidia and aleuroconidia. After phylogenetic analyses, the species Thielaviopsis ethacetica could be proven as the etiological agent of the dry basal rot of oil palm and could be distinguished from T. paradoxa.
DOI: 10.6084/m9.figshare.14279249
title: Temporal dynamics of grapevine downy mildew in Piwi varieties in San Michele all’Adige Region, Trentino - Italy

description: ABSTRACT Downy mildew (Plasmopara viticola), a biotrophic oomycete, is the causal agent of the main disease of the grapevine. The objective of this study was to evaluate the response of nine Piwi varieties (from the German word: “Pilzwiderstandsfähige” = “Disease-resistant”) showing constitutive resistance to downy mildew (P. viticola) and a Vitis vinifera variety (susceptible) as control in an experimental vineyard of Fundazione Edmund Mach (FEM), located in San Michele All’Adige, in the Trentino region of Italy. The vineyard has been conducted for ten years without any chemical treatment and was evaluated in the 2017 crop season. The different varieties were evaluated for downy mildew intensity in the field and stomatal density in the Phytopathology Laboratory of FEM. To evaluate stomatal density, ten leaves of each genotype were collected in the phenological stage véraison, immediately taken to the laboratory and prepared for observation through a magnifying glass (40x), according to Boso et al. (2). In the field trial, mildew incidence and severity assessments were carried out weekly from the beginning of the first symptoms/signs and the epidemics were compared in relation to: a) beginning of symptom/sign appearance (BSA); b) time to reach maximum disease incidence and severity (TRMDI and TRMDS); c) maximum value of disease incidence and severity (Imax and Smax), and d) area under the disease incidence and severity progress curve (AUIDPC and AUSDPC). Piwi varieties presented a mean reduction of 93.9% in mildew severity in relation to the vine variety ‘Pinot Grigio’. The varieties ‘Jasmine’, ‘Muscaris’ and ‘Regent’ showed the lowest intensity of downy mildew infection in the field in the 2017 harvest under the edaphoclimatic conditions of Trentino, Italy. There was a positive relationship between the lowest stomatal density per leaf area and the greatest resistance to P. viticola in the field. Piwi varieties appear as a cultivation option with the aim of reducing the use of pesticides and as sustainable support for the Trentino wine industry.
DOI: 10.6084/m9.figshare.14279249.v1
title: Temporal dynamics of grapevine downy mildew in Piwi varieties in San Michele all’Adige Region, Trentino - Italy

description: ABSTRACT Downy mildew (Plasmopara viticola), a biotrophic oomycete, is the causal agent of the main disease of the grapevine. The objective of this study was to evaluate the response of nine Piwi varieties (from the German word: “Pilzwiderstandsfähige” = “Disease-resistant”) showing constitutive resistance to downy mildew (P. viticola) and a Vitis vinifera variety (susceptible) as control in an experimental vineyard of Fundazione Edmund Mach (FEM), located in San Michele All’Adige, in the Trentino region of Italy. The vineyard has been conducted for ten years without any chemical treatment and was evaluated in the 2017 crop season. The different varieties were evaluated for downy mildew intensity in the field and stomatal density in the Phytopathology Laboratory of FEM. To evaluate stomatal density, ten leaves of each genotype were collected in the phenological stage véraison, immediately taken to the laboratory and prepared for observation through a magnifying glass (40x), according to Boso et al. (2). In the field trial, mildew incidence and severity assessments were carried out weekly from the beginning of the first symptoms/signs and the epidemics were compared in relation to: a) beginning of symptom/sign appearance (BSA); b) time to reach maximum disease incidence and severity (TRMDI and TRMDS); c) maximum value of disease incidence and severity (Imax and Smax), and d) area under the disease incidence and severity progress curve (AUIDPC and AUSDPC). Piwi varieties presented a mean reduction of 93.9% in mildew severity in relation to the vine variety ‘Pinot Grigio’. The varieties ‘Jasmine’, ‘Muscaris’ and ‘Regent’ showed the lowest intensity of downy mildew infection in the field in the 2017 harvest under the edaphoclimatic conditions of Trentino, Italy. There was a positive relationship between the lowest stomatal density per leaf area and the greatest resistance to P. viticola in the field. Piwi varieties appear as a cultivation option with the aim of reducing the use of pesticides and as sustainable support for the Trentino wine industry.
DOI: 10.6084/m9.figshare.14279248.v1
title: Incidence and molecular characterization of badnavírus in germplasm banks of yam in Brazil

description: ABSTRACT Badnaviruses (family Caulimoviridae) have semicircular dsDNA genomes encapsidated into bacilliform particles. Dioscorea bacilliform virus (DBV) is an important Badnavirus infecting several species of Dioscorea (yam) in the southern hemisphere. In this study, 235 yam leaf samples were collected from different germplasm banks maintained by “Luiz de Queiroz” College of Agriculture (ESALQ/USP), Federal University of Viçosa (UFV) and Federal University of Recôncavo da Bahia (UFRB). The average incidence of badnavirus in the evaluated samples was 75.3%. Molecular and phylogenetic analyses, carried out from 42 nucleotide sequences, of the badnavirus RT/RNaseH region, revealed the occurrence of Dioscorea bacilliform AL virus (DBALV) and Dioscorea bacilliform SN virus (DBSNV) in different yam species. So far, only DBALV has been reported in yams in Brazil, being restricted to the Northeast region. Therefore, this is the first report of DBSNV infecting yam crop in the country. In addition to the episomal species, endogenous sequences were detected, and the percentage of nucleotide identity varied between 89% and 100% with endogenous Dioscorea bacilliform virus (eDBV), belonging to groups 9 and 12. The obtained results corroborate the hypothesis that DBALV and DBSNV are present in yam propagating materials and are widely disseminated in Brazil.
DOI: 10.6084/m9.figshare.14279255
title: Control of Fusarium verticillioides in corn seeds with ginger essential oil.

description: ABSTRACT The behavior of isolates of the species Fusarium verticillioides present in different corn-producing microregions, as well as the behavior of hybrids used in these regions in the presence of the above-mentioned pathogen whe ther in seeds, plant stems or crop remains, needs to be evaluated with the aim of better managing the diseases they cause. Alternative met hods with a smaller quantity of products harmful to the health have been employed to control diseases, reducing the use of pesticides and contributing to more sustainable agriculture. The objective of this study was to evaluate the control of F. verticillioides in corn seeds with essential oil (EO) of ginger, as well as the presence of this pathogen in the stem of plants originated from these seeds. Naturally infested seeds were treated with ginger essential oil at six concentrations (0, 1%, 2%, 3%, 4% and 5%). Evaluation included standard germination, seed health, emergence and emergence speed index in the substrate, and presence of pathogens in the seedlings. Experimental design was completely randomized for germination and health tests and in randomized blocks for the tests of emergence and disease incidence in the stems of corn seedlings. Ginger EO, at the concentrations 0 (zero), 1%, 2%, 3%, 4% and 5%, did not affect corn seed germinati on considering the evaluated hybrid and provided lower F. verticillioides incidence percentage at 1%, 4% and 5%. The oscillation in the germination pe rcentage of seeds treated with different concentrations of ginger EO was inversely proportional to the presence of the fungus F. verticillioides in the seeds. The emergence speed index of seeds treated with different concentrations of ginger EO was superior at the highest concentration. Ginger EO can be used in the treatment of corn seeds to control F. verticillioides at the evaluated concentrations.
DOI: 10.6084/m9.figshare.14279255.v1
title: Control of Fusarium verticillioides in corn seeds with ginger essential oil.

description: ABSTRACT The behavior of isolates of the species Fusarium verticillioides present in different corn-producing microregions, as well as the behavior of hybrids used in these regions in the presence of the above-mentioned pathogen whe ther in seeds, plant stems or crop remains, needs to be evaluated with the aim of better managing the diseases they cause. Alternative met hods with a smaller quantity of products harmful to the health have been employed to control diseases, reducing the use of pesticides and contributing to more sustainable agriculture. The objective of this study was to evaluate the control of F. verticillioides in corn seeds with essential oil (EO) of ginger, as well as the presence of this pathogen in the stem of plants originated from these seeds. Naturally infested seeds were treated with ginger essential oil at six concentrations (0, 1%, 2%, 3%, 4% and 5%). Evaluation included standard germination, seed health, emergence and emergence speed index in the substrate, and presence of pathogens in the seedlings. Experimental design was completely randomized for germination and health tests and in randomized blocks for the tests of emergence and disease incidence in the stems of corn seedlings. Ginger EO, at the concentrations 0 (zero), 1%, 2%, 3%, 4% and 5%, did not affect corn seed germinati on considering the evaluated hybrid and provided lower F. verticillioides incidence percentage at 1%, 4% and 5%. The oscillation in the germination pe rcentage of seeds treated with different concentrations of ginger EO was inversely proportional to the presence of the fungus F. verticillioides in the seeds. The emergence speed index of seeds treated with different concentrations of ginger EO was superior at the highest concentration. Ginger EO can be used in the treatment of corn seeds to control F. verticillioides at the evaluated concentrations.
DOI: 10.6084/m9.figshare.14279252
title: Potential use of fresh mulch to curb potato late blight epidemics in Brazil

description: ABSTRACT Field experiments were conducted during spring 2014 and fall and spring 2015 to determine the effect of fresh mulch on the development of Phytophthora infestans epidemics, in Lapa Municipality, Parana State, southern Brazil. The used cultivars were ‘Agata’, susceptible, and ‘BRS Ana’, moderately susceptible. The main treatment consisted in manually applying a 10cm-thick layer of fresh mulch when potato sprouts were emerging. Fresh mulch was prepared with plants available at that time of the year. For the spring experiments, fresh mulch was a mixture of oats, rye grass and wild radish (60 t/ha) and for the fall experiment, semi-ripe elephant grass (90 t/ha). Plots consisted of six 10m-long rows, spaced at 0.8m, containing 28 plants per row. Experimental design was in completely randomized blocks with four replicates. Natural inoculum was adopted. Percentage of leaf area was weekly estimated until the end of the plant cycle and the area under the disease progress curve (AUDPC) was calculated. Application of fresh mulch significantly reduced AUDPC by 32.1%, 12.4% and 23.1%, compared to control in all seasons, for ‘BRS Ana’ and by 26.1%, 2.8% and 12.0% for ‘Agata’. Application of fresh mulch showed to be a promising practice for the integrated management of late blight and for the protection of yields, especially in periods more favorable to the development of the disease. More detailed studies should be conducted on the plant type and amount of fresh mulch to be used, as well as on the possibility of reducing concentrations or increasing intervals between fungicide sprays.
DOI: 10.6084/m9.figshare.14279252.v1
title: Potential use of fresh mulch to curb potato late blight epidemics in Brazil

description: ABSTRACT Field experiments were conducted during spring 2014 and fall and spring 2015 to determine the effect of fresh mulch on the development of Phytophthora infestans epidemics, in Lapa Municipality, Parana State, southern Brazil. The used cultivars were ‘Agata’, susceptible, and ‘BRS Ana’, moderately susceptible. The main treatment consisted in manually applying a 10cm-thick layer of fresh mulch when potato sprouts were emerging. Fresh mulch was prepared with plants available at that time of the year. For the spring experiments, fresh mulch was a mixture of oats, rye grass and wild radish (60 t/ha) and for the fall experiment, semi-ripe elephant grass (90 t/ha). Plots consisted of six 10m-long rows, spaced at 0.8m, containing 28 plants per row. Experimental design was in completely randomized blocks with four replicates. Natural inoculum was adopted. Percentage of leaf area was weekly estimated until the end of the plant cycle and the area under the disease progress curve (AUDPC) was calculated. Application of fresh mulch significantly reduced AUDPC by 32.1%, 12.4% and 23.1%, compared to control in all seasons, for ‘BRS Ana’ and by 26.1%, 2.8% and 12.0% for ‘Agata’. Application of fresh mulch showed to be a promising practice for the integrated management of late blight and for the protection of yields, especially in periods more favorable to the development of the disease. More detailed studies should be conducted on the plant type and amount of fresh mulch to be used, as well as on the possibility of reducing concentrations or increasing intervals between fungicide sprays.
DOI: 10.6084/m9.figshare.14279257
title: Reduction in wheat blast severity with foliar application of zinc sulfate

description: ABSTRACT Wheat blast, caused by the fungus Magnaporthe oryzae, is among the factors of highest risk for wheat production because losses can be greater than 90% in crop seasons with favorable environmental conditions to the development of this disease. The objective of this study was to evaluate the effect of zinc sulfate on M. oryzae infection in wheat leaves, as well as hydrogen peroxide production and cell death in the plant. The disease severity was evaluated as a function of foliar application of Zn (0, 0.4%, 0.8%, 1.2% and 1.6% zinc sulfate) in four different wheat cultivars (‘Mirante’, ‘Safira’, ‘Madre Pérola’ and ‘Ônix’). In addition, with the aim of verifying which histological component is possibly involved in reducing blast severity, an experiment was carried out with application of 0.4% zinc sulfate onto the 3rd leaf and without application (distilled water) in the cultivar ‘Safira’, which is susceptible to this disease. Three days after ZnSO4 application, the plants were inoculated with 104 conidia.mL-1 suspension of M. oryzae and kept in a humid chamber during 24 h; leaves were collected at 18, 24, 30, 36, 48 and 72 hours after inoculation (hai). The leaves were fragmented and bleached for histopathological evaluations of the responses of hydrogen peroxide production and cell death during wheat infection by M. oryzae. Wheat blast severity reduced when zinc was applied at different concentrations in all cultivars, except ‘Onyx’. Zinc at 0.4% had no effect on infection events, except for cell death at 48 hai. The wheat cultivar and the zinc sulfate concentrations influenced the disease severity reduction efficiency.
DOI: 10.6084/m9.figshare.14279257.v1
title: Reduction in wheat blast severity with foliar application of zinc sulfate

description: ABSTRACT Wheat blast, caused by the fungus Magnaporthe oryzae, is among the factors of highest risk for wheat production because losses can be greater than 90% in crop seasons with favorable environmental conditions to the development of this disease. The objective of this study was to evaluate the effect of zinc sulfate on M. oryzae infection in wheat leaves, as well as hydrogen peroxide production and cell death in the plant. The disease severity was evaluated as a function of foliar application of Zn (0, 0.4%, 0.8%, 1.2% and 1.6% zinc sulfate) in four different wheat cultivars (‘Mirante’, ‘Safira’, ‘Madre Pérola’ and ‘Ônix’). In addition, with the aim of verifying which histological component is possibly involved in reducing blast severity, an experiment was carried out with application of 0.4% zinc sulfate onto the 3rd leaf and without application (distilled water) in the cultivar ‘Safira’, which is susceptible to this disease. Three days after ZnSO4 application, the plants were inoculated with 104 conidia.mL-1 suspension of M. oryzae and kept in a humid chamber during 24 h; leaves were collected at 18, 24, 30, 36, 48 and 72 hours after inoculation (hai). The leaves were fragmented and bleached for histopathological evaluations of the responses of hydrogen peroxide production and cell death during wheat infection by M. oryzae. Wheat blast severity reduced when zinc was applied at different concentrations in all cultivars, except ‘Onyx’. Zinc at 0.4% had no effect on infection events, except for cell death at 48 hai. The wheat cultivar and the zinc sulfate concentrations influenced the disease severity reduction efficiency.
DOI: 10.6084/m9.figshare.14268473
title: Damage to the corn crop due to the reduction of leaf area by artificial defoliation and diseases

description: ABSTRACT Damage caused by diseases that occur during the vegetative stages of corn results in decreased grain yield, and chemical control is one of the strategies to allow damage reduction. The objective of this study was to quantify the damage to corn plants as a function of leaf area reduction caused by the disease complex, associated or not with leaf removal from different positions in the plant. The experiment was carried out in the field, in a completely randomized block design with four replicates and 10 x 3 factorial arrangement of treatments. The first factor corresponded to the association of two fungicides at different doses, combined with artificial defoliation at the first fungicide spraying. The second factor consisted of application at different stages (VT, R1 and R2). The used hybrid was Formula TL®, which is susceptible to cercosporiosis, polysora rust and white spot. Disease progress, leaf area index and grain yield were evaluated. Preventive application of fungicides (phenological stage VT), regardless of leaf removal from the plant, provided less disease progress and less damage. Higher significant values of grain mass and yield were obtained with fungicide application without leaf removal, regardless of the phenological stage receiving the application.
DOI: 10.6084/m9.figshare.14268473.v1
title: Damage to the corn crop due to the reduction of leaf area by artificial defoliation and diseases

description: ABSTRACT Damage caused by diseases that occur during the vegetative stages of corn results in decreased grain yield, and chemical control is one of the strategies to allow damage reduction. The objective of this study was to quantify the damage to corn plants as a function of leaf area reduction caused by the disease complex, associated or not with leaf removal from different positions in the plant. The experiment was carried out in the field, in a completely randomized block design with four replicates and 10 x 3 factorial arrangement of treatments. The first factor corresponded to the association of two fungicides at different doses, combined with artificial defoliation at the first fungicide spraying. The second factor consisted of application at different stages (VT, R1 and R2). The used hybrid was Formula TL®, which is susceptible to cercosporiosis, polysora rust and white spot. Disease progress, leaf area index and grain yield were evaluated. Preventive application of fungicides (phenological stage VT), regardless of leaf removal from the plant, provided less disease progress and less damage. Higher significant values of grain mass and yield were obtained with fungicide application without leaf removal, regardless of the phenological stage receiving the application.