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Miguel Ángel Cantamutto - One of the best experts on this subject based on the ideXlab platform.
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Vicia villosa ssp villosa roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2018Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE < 10.1) despite the environmental variability among years. The additive effect of each submodel clearly improved the explanatory capacity of the field emergence patterns. The alleviation of PD synchronizes the timing for hairy vetch germination, while the PY determines the seedbank persistence. These outcomes suggest the potential applicability of the proposed modelling approach within management decision support systems.
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Vicia villosa ssp. villosa Roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2017Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE
Guillermo R. Chantre - One of the best experts on this subject based on the ideXlab platform.
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Vicia villosa ssp villosa roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2018Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE < 10.1) despite the environmental variability among years. The additive effect of each submodel clearly improved the explanatory capacity of the field emergence patterns. The alleviation of PD synchronizes the timing for hairy vetch germination, while the PY determines the seedbank persistence. These outcomes suggest the potential applicability of the proposed modelling approach within management decision support systems.
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Vicia villosa ssp. villosa Roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2017Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE
Yoshiharu Fujii - One of the best experts on this subject based on the ideXlab platform.
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Carbon sources of natural cyanamide in Vicia villosa subsp. varia.
Natural Product Research, 2010Co-Authors: Tsunashi Kamo, Syuntaro Hiradate, Mitsuru Hirota, Ryohei Kasahara, Shun Abe, Mami Sugano, Hiroko Yamaya, Yoshiharu FujiiAbstract:The 13C labels of [13C]carbon dioxide and D-[13C6]glucose were incorporated into cyanamide (NH2CN) when they were administered to Vicia villosa subsp. varia shoots. In contrast, the administration of sodium [2,3-13C2]pyruvate did not affect the relative area of the [M + 1]+ ion of cyanamide in the gas chromatography–mass spectrometry analysis. [2,3-13C2]Pyruvate was incorporated into organic acids that are part of the citric acid cycle, such as succinate and fumarate, confirming that the shoots absorbed and metabolised it. These observations demonstrated that the carbon atom of cyanamide is derived from any of the carbohydrates that are present upstream of pyruvate in the metabolic pathway.
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Biosynthetic origin of the nitrogen atom in cyanamide in Vicia villosa subsp. varia
Soil Science and Plant Nutrition, 2009Co-Authors: Tsunashi Kamo, Kenji Kato, Syuntaro Hiradate, Mitsuru Hirota, Shun Abe, Hiroko Yamaya, Yoshiharu FujiiAbstract:Abstract Natural cyanamide (NH2CN) has recently been found in three Leguminosae plants: Vicia villosa subsp. varia, Vicia cracca and Robinia pseudo-acacia. As cyanamide has long been thought to be absent in nature, its physiological role and biosynthesis are totally unknown. In the present study, we demonstrated the incorporation of 15N from [15N]nitrate and [15N]ammonium into cyanamide using shoots of V. villosa subsp. varia, which ruled out the possibility that nodules are essential in cyanamide biosynthesis. We also applied [15N2]cyanamide to shoots of V. villosa subsp. varia to monitor its turnover, and detected [15N2]cyanamide in the leaves within 4 h; it was present without detectable degradation for more than 4 days. In contrast, maximum incorporation of 15N into cyanamide molecules was observed after 4 days of feeding the shoots with 15N-labeled inorganic ions and l-[amide-15N]-glutamine, indicating that these nitrogenous compounds are distant precursors of cyanamide. Although the guanidino group ...
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Evidence of cyanamide production in hairy vetch Vicia villosa.
Natural Product Research, 2006Co-Authors: Tsunashi Kamo, Kenji Kato, Syuntaro Hiradate, Eri Nakajima, Yoshiharu Fujii, Mitsuru HirotaAbstract:Cyanamide (NH2CN) has recently been isolated as a plant growth inhibitor from Vicia villosa, which is the first discovery of cyanamide from natural sources. To reveal the presence of the biosynthesized cyanamide in plants, 3.4 mM potassium (15N)nitrate was administered to 15- to 35-day-old plants of V. villosa, from which the cyanamide was purified and subjected to GC/MS analysis. The isotopic ratio 15N/(14N + 15N) of the cyanamide was calculated to be 0.143, while that of the cyanamide extracted from V. villosa grown in the presence of a natural N source was 0.0065. The 15N-enrichment proved de novo biosynthesis of cyanamide.
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First Isolation of Natural Cyanamide as a Possible Allelochemical from Hairy Vetch Vicia villosa
Journal of Chemical Ecology, 2003Co-Authors: Tsunashi Kamo, Syuntaro Hiradate, Yoshiharu FujiiAbstract:Cyanamide was isolated from the leaves and stems of hairy vetch ( Vicia villosa ), guided by plant growth inhibitory activity against lettuce ( Lectuca sativa ) seedlings. A large proportion of the inhibitory activity in the crude extract was explained by the presence of cyanamide, suggesting it to be a possible allelochemical in this species. The amount in a 9-day-old seedling, which had been grown without nutrients, reached approx. 40 times that of a nongerminated seed, demonstrating cyanamide biosynthesis in the seedlings. This is the first report on the isolation of a possible allelochemical from hairy vetch and also of the finding of cyanamide as a natural product.
Juan P. Renzi - One of the best experts on this subject based on the ideXlab platform.
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Vicia villosa ssp villosa roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2018Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE < 10.1) despite the environmental variability among years. The additive effect of each submodel clearly improved the explanatory capacity of the field emergence patterns. The alleviation of PD synchronizes the timing for hairy vetch germination, while the PY determines the seedbank persistence. These outcomes suggest the potential applicability of the proposed modelling approach within management decision support systems.
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Vicia villosa ssp. villosa Roth field emergence model in a semiarid agroecosystem
Grass and Forage Science, 2017Co-Authors: Juan P. Renzi, Guillermo R. Chantre, Miguel Ángel CantamuttoAbstract:Hairy vetch (Vicia villosa Roth) is a winter annual legume cultivated for pasture and hay with the capability for natural reseeding. Vicia villosa increases N concentrations in the soil, thus contributing to the sustainability of semiarid regions. However, under rotations of 1–2 years of pasture followed by 1 year of crop (1:1–2:1), hairy vetch could become a problematic volunteer weed in the winter cereal crop phase. This study aimed to develop a mechanistic model for hairy vetch seedling emergence in order to (i) estimate the natural reseeding of hairy vetch in the pasture phase of the field rotation, or (ii) develop control strategies considering hairy vetch as a volunteer weed in the winter cereal phase. The proposed model simulates the pattern of field emergence of hairy vetch after natural seed dispersal by integrating four submodels: (i) physical (PY) dormancy release dynamics, (ii) physiological dormancy (PD) release and germination thermal requirements, (iii) hydro-time requirements for germination, and (iv) pre-emergence growth respectively. The developed field emergence model was validated with independent field emergence data during 2013, 2014 and 2015. The model adequately predicted the timing and magnitude of field emergence flushes (RMSE
Eduardo Osinaga - One of the best experts on this subject based on the ideXlab platform.
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Monoclonal antibodies against the Tn-specific isolectin B4 from Vicia villosa seeds: characterization of the epitope of the blocking antibody VV34.
Hybridoma and Hybridomics, 2004Co-Authors: Andrea Medeiros, Nora Berois, Henia Balter, Ana Robles, Enrique Pérez-payá, Juan J. Calvete, Ana Gimenez, Eduardo OsinagaAbstract:Vicia villosa isolectin B4 (VVLB4) recognizes the Tn antigen (GalNAc-O-Ser/Thr) exposed in certain human carcinomas. We have produced anti-VVLB4 monoclonal antibodies (MAbs), and their lectin recog...
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monoclonal antibodies against the tn specific isolectin b4 from Vicia villosa seeds characterization of the epitope of the blocking antibody vv34
Hybridoma and Hybridomics, 2004Co-Authors: Andrea Medeiros, Nora Berois, Henia Balter, Ana Robles, Enrique Perezpaya, Juan J. Calvete, Ana Gimenez, Eduardo OsinagaAbstract:: Vicia villosa isolectin B4 (VVLB4) recognizes the Tn antigen (GalNAc-O-Ser/Thr) exposed in certain human carcinomas. We have produced anti-VVLB4 monoclonal antibodies (MAbs), and their lectin recognition selectivity was assessed by ELISA and Western blot against the purified Gal/GalNAc-specific lectins from Vicia villosa, Salvia sclarea, Helix pomatia, Arachis hypogaea, Glycine max, and Dolichos biflorus. The antibodies were also tested for their ability to block the binding of VVLB4 to the Tn antigen expressed on immobilized asialo ovine submaxillary mucin. Two MAbs, VV34 and VV2, specifically recognized VVLB4 and impaired the binding of the lectin to the Tn antigen by 98% and 21%, respectively. On the other hand, MAbs VV1 and VV22 cross-reacted with other purified lectins. The four antibodies recognized native and periodate-oxidized nonreduced as well as reduced VVLB4 after SDS-PAGE and Western blot, suggesting that they were recognizing continuous polypeptide epitopes. The VV34 antibody recognized two tryptic peptides (7-29 and 96-106) from VVLB4, which are contiguous in the three-dimensional structure of the lectin. The minimum structural determinant of the epitope was mapped to the polypeptide stretch (18)LILQED(23) using a set of overlapping synthetic peptides. This region of the molecule encompasses the C-terminal part of the loop joining strands beta1 and beta2 and the N-terminal part of beta2, and is located about 20-25 A away from the center of the Tn-combining site.
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amino acid sequence and three dimensional structure of the tn specific isolectin b4 from Vicia villosa
FEBS Letters, 1997Co-Authors: Eduardo Osinaga, Diana Tello, Gisele A Tavares, Carlos Cervenansky, Luc Camoin, Mario Antonio Bianchet, Carlos Batthyany, A Roseto, Rosario Duran, Pedro Maria AlzariAbstract:Abstract The partial amino acid sequence of the tetrameric isolectin B4 from Vicia villosa seeds has been determined by peptide analysis, and its three-dimensional structure solved by molecular replacement techniques and refined at 2.9 A resolution to a crystallographic R-factor of 21%. Each subunit displays the thirteen-stranded β-barrel topology characteristic of legume lectins. The amino acid residues involved in metal- and sugar-binding are similar to those of other GalNAc-specific lectins, indicating that residues outside the carbohydrate-binding pocket modulate the affinity for the Tn glycopeptide. Isolectin B4 displays an unusual quaternary structure, probably due to protein glycosylation.
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Amino acid sequence and three‐dimensional structure of the Tn‐specific isolectin B4 from Vicia villosa
FEBS Letters, 1997Co-Authors: Eduardo Osinaga, Diana Tello, Gisele A Tavares, Carlos Cervenansky, Luc Camoin, Mario Antonio Bianchet, Carlos Batthyany, A Roseto, Rosario Duran, Pedro Maria AlzariAbstract:Abstract The partial amino acid sequence of the tetrameric isolectin B4 from Vicia villosa seeds has been determined by peptide analysis, and its three-dimensional structure solved by molecular replacement techniques and refined at 2.9 A resolution to a crystallographic R-factor of 21%. Each subunit displays the thirteen-stranded β-barrel topology characteristic of legume lectins. The amino acid residues involved in metal- and sugar-binding are similar to those of other GalNAc-specific lectins, indicating that residues outside the carbohydrate-binding pocket modulate the affinity for the Tn glycopeptide. Isolectin B4 displays an unusual quaternary structure, probably due to protein glycosylation.
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Crystallization and Preliminary Crystallographic Analysis of a Tetrameric Isolectin from Vicia villosa, Specific for the Tn Antigen
Journal of Molecular Biology, 1993Co-Authors: Jean-luc Eiselé, Eduardo Osinaga, Diana Tello, A Roseto, Pedro Maria AlzariAbstract:Isolectin B4 isolated from Vicia villosa seeds is specific for the Tn antigen, a carcinoma-associated molecular marker. Crystals of the isolectin grown in the presence of carbohydrate are tetragonal, space group P 41 (or P43), with a = 91·3 A, c = 151·7 A and one tetramer in the asymmetric unit. The crystals diffract X-rays to 2·8 A resolution and are suitable for high-resolution structural analysis.
