Sustainable management of mineral nutrition in vineyards, as well as in other fruit plantations, should aim at exploiting the use of internal sources of nutrients, in order to reduce the need for external nutrient inputs. In this paper we explore the potential of the grassed alleys to provide nutrients to the vines. We followed for one vegetative season the decomposition of ryegrass and clover, frequently present as floor vegetation in vineyards, using litter bags filled with 15 N-enriched grass material. In addition, we quantified the amount of nitrogen (N) transferred from the decomposing litter to field-grown grapevines. Ryegrass and clover had a relatively rapid decomposition rate, with a loss of C approaching 80% in only 16 weeks. The release of nutrients was particularly fast for potassium (95% in 16 weeks) followed by nitrogen (80%), calcium (70-80%), phosphorous (65-85%), magnesium (70-75%), and sulfur (60-70%). In spite of the rapid release of N from decomposing material, the N uptake by grapevines was on average less than 4% of the initial amount of N present in the litter of ryegrass and clover. Even if N release during the decomposition of mowed perennial ryegrass and white clover little contributed to the N nutrition of grapevine in the same growing season, most N from mowed grassed was still recovered in the soil.

O nitrogênio (N) aplicado na superfície do solo em vinhedos pode ser perdido por volatilização ou lixiviação, sendo uma das possíveis explicações para o baixo aproveitamento de N pelas videiras. O trabalho objetivou avaliar as perdas de N por volatilização e lixiviação do N mineral em solo cultivado com videira submetida à adubação nitrogenada. Foram instalados dois experimentos em um vinhedo de Cabernet Sauvignon, em Rosário do Sul (RS), Brasil. No experimento 1, foram instalados lisímetros no solo que recebeu a aplicação de 0, 40, 80 e 120kg de N ha-1 ano-1 na forma de ureia e, durante o período de agosto a dezembro de 2009, foi coletada a solução do solo para a análise de N mineral. No experimento 2, foram instaladas câmaras coletoras no solo que recebeu, em agosto de 2010, a aplicação de 0, 20, 40, e 80kg de N ha-1 ano-1 na forma de ureia, 40kg de N ha-1 ano-1 de composto orgânico e 40kg de N ha-1 ano-1 de ureia revestida com polímeros, para avaliar a volatilização de N-NH3 do momento da aplicação até 80 horas depois da aplicação. As maiores concentrações de nitrogênio mineral na solução lixiviada foram encontradas nas doses mais elevadas de fertilizante mineral aplicado e ao longo da brotação e florescimento das videiras, o que pode diminuir o aproveitamento do nutriente pelas plantas. Os maiores fluxos e perdas de amônia do solo cultivado com videira para a atmosfera aconteceram nas doses mais elevadas de nitrogênio mineral aplicado, especialmente, depois de 44 horas da sua aplicação sobre a superfície do solo. A aplicação de ureia revestida com polímeros e composto orgânico promoveram as menores perdas de amônia por volatilização, o que pode estimular o aproveitamento de nitrogênio pelas videiras.

Heavy metal phytoremediation of vineyards by native cover crops. Intercropping decrease Cu þ2 in soil solution of Cu-contaminated soils. Native plants contribute to soil conservation and nutrient cycling in vineyards.

Produção e composição química da uva de videiras Cabernet Sauvignon submetidas à adubação nitrogenada Grapes yield and chemistry composition in Cabernet Sauvignon grapevine with nitrogen fertilization RESUMOA adubação nitrogenada em videiras é realizada para suprir a demanda da planta pelo nutriente. Porém, o nitrogênio (N)

The continuous use of cupric fungicides in vineyards, mainly copper sulfate (as a component of the bordeaux mixture), has increased Cu concentration in soils to levels near or even above the maximum established by the Commission of Soil Chemistry and Fertility of the States of Santa Catarina and Rio Grande do Sul, Brazil. Besides the total content, the fractions of the element along the soil profile must be known, because the total content of Cu in the soil is not sufficient to express its environmental impact. The objective of this study was to evaluate the variation of Cu contentes along the soil profile and its speciation and partitioning in 29 soil samples from vineyards in the state of Rio Grande do Sul, Brazil. Samples were collected in areas cropped with vineyards older than 15 years that had been frequently treated with the bordeaux mixture. These samples were from Nitosols, Acrisols, Cambisols and Leptosols and were analysed by sequential extractions and several chemical extractors. Soils had diverse chemical and physical attributes: clay content in the plowed layer (0-0.2 m) ranged from 120 to 610 g kg(-1), pH ranged from 5.3 to 7.3 and organic carbon contents varied from 2.9 to 51 g dm(-3). Among the 29 samples, 16 had the total Cu above the maximum limit allowed by the European Community regulations (140 mg kg(-1)). The average amount of Cu bonded to the oxide fraction accounted for 49.5% of the total Cu.

A significant quantity of nutrients in vineyards may return to the soil each year through decomposition of residues from cover plants. This study aimed to evaluate biomass decomposition and nutrient release from residues of black oats and hairy vetch deposited in the vines rows, with and without plastic shelter, and in the between-row areas throughout the vegetative and productive cycle of the plants. The study was conducted in a commercial vineyard in Bento Gonçalves, RS, Brazil, from October 2008 to February 2009. Black oat (Avena strigosa) and hairy vetch (Vicia villosa) residues were collected, subjected to chemical (C, N, P, K, Ca, and Mg) and biochemical (cellulose - Cel, hemicellulose - Hem, and lignin - Lig content) analyses, and placed in litter bags, which were deposited in vines rows without plastic shelter (VPRWS), in vines rows with plastic shelter (VPRS), and in the between-row areas (BR). We collected the residues at 0, 33, 58, 76, and 110 days after deposition of the litter bags, prepared the material, and subjected it to analysis of total N, P, K, Ca, and Mg content. The VPRS contained the largest quantities and percentages of dry matter and residual nutrients (except for Ca) in black oat residues from October to February, which coincides with the period from flowering up to grape harvest. This practice led to greater protection of the soil surface, avoiding surface runoff of the solution derived from between the rows, but it retarded nutrient cycling. The rate of biomass decomposition and nutrient release from hairy vetch residues from October to February was not affected by the position of deposition of the residues in the vineyard, which may especially be attributed to the lower values of the C/N and Lig/N ratios. Regardless of the type of residue, black oat or hairy vetch, the greatest decomposition and nutrient release mainly occurred up to 33 days after deposition of the residues on the soil surface, which coincided with the flowering of the grapevines, which is one of the phenological stages of greatest demand for nutrients.

The SPAD reading may be used in estimating total nitrogen content (N) in leaves and even in estimating grape yield in grapevines. The objective of this study was to estimate total N content in leaves and grape yield using the SPAD-502 in grapevines submitted to nitrogen fertilization in soils with clayey and sandy texture. In 2008, two experiments were installed in the Southern region of Brazil. In experiment 1, Cabernet Sauvignon grapevines were planted in a soil with clayey texture and with application of 10, 20, 40 and 80 kg·N·ha^-1·year^-1. In experiment 2, Cabernet Sauvignon grapevines were planted in a soil with sandy texture and with the application of 0, 10, 15, 20, 40, 80 and 120 kg·N·ha^-1·year^-1. In the grapevines of the two experiments and during the period from 2008 to 2010, SPAD readings were made on leaves throughout the flowering period and at change in color of the berries using the portable chlorophyll meter Minolta-SPAD-502. The leaves were collected, dried, ground and submitted to analysis of the total N content. In addition, grape yield per hectare was evaluated. The SPAD-502 readings estimated the total N content in flowering and at change in color of the berries in the Cabernet Sauvignon grapevines grown on soils with clayey texture and sandy texture, especially in the first year of evaluation. However, the precision of the SPAD-502 readings is low, with there being no relationship between the SPAD-502 readings and grape yield

RESUMO -No Rio Grande do Sul, o teor de N na folha inteira ou pecíolo e a expectativa de produção têm sido usados tanto para a tomada de decisão quanto no estabelecimento da dose de N a ser aplicada na cultura da videira. Entretanto, se carece de conhecimentos sobre a utilização, a distribuição e a acumulação na planta do N aplicado. O presente trabalho objetivou estimar o destino do N em videiras produtivas quando aplicado na época do inchamento das gemas. O experimento foi conduzido na safra 2002-2003 em um vinhedo de viníferas, cvs. Chardonnay e Riesling Renano, na Embrapa Uva e Vinho, em Bento Gonçalves -RS, sobre um Neossolo Litólico. As videiras receberam a aplicação de 15,91g N planta -1 no inchamento das gemas, correspondendo a 40 kg N ha -1 , enriquecido com 4% de átomos 15 N em excesso. Foram coletadas gemas brotadas e folhas na parte central do ramo emitido no ano, em oito épocas na cv. Chardonnay e sete épocas na cv. Riesling Renano. Na última coleta das folhas, as videiras foram cortadas e separadas em cachos, folhas, ramos do ano, ramos dos anos anteriores e caule. Foram secadas, determinada a produção de matéria seca e os teores de N total e 15 N. Os resultados mostraram que a maior porcentagem de N nas folhas das videiras, cvs. Chardonnay e Riesling Renano, na brotação até a colheita da uva, é derivada de formas diferentes de N aplicado no inchamento das gemas. Na colheita da uva, a maior quantidade do N acumulado nas partes anuais e perenes das videiras é derivada do N do solo, sendo muito pequenas as quantidades de N aplicado no inchamento das gemas armazenado nas partes perenes. Termos de Indexação: Adubação nitrogenada, absorção N, distribuição N, isótopo 15 N, videira. NITROGEN DESTINY IN 'CHARDONNAY' AND 'RIESLING RENANO' GRAPEVINES, WHEN APPLIED IN BUD BREAKABSTRACT -The grapevines N fertilization levels in Southern Brazil use to be accounted as function of N leaf and leaf petioles rates for a limit yield expectation, without any information about the inner N dynamics in the grapevines. This experiment was carried out in 2002/03, to estimate the N destiny as N broadcasted on the vineyard soil with Chardonnay and Riesling Renano grapevines, at a Udorthent soil in, Bento Gonçalves, Southern Brazil. The vines received the application of 15.91g N plant -1 , 40 kg N ha -1 , with 4% atoms 15 N, in bud break. The buds and leaves were collected in the central parts of the year branch eight different times in the Chardonnay grapes and seven times in the Riesling Renano grapes. The grapevines in the last collection of the leaves were separated in leaves, fruits, year branches, branches with two years and stem, and then were oven-dried, weighted and analyzed total N and 15 N contents. The results showed that the larger percentage of N in the leaves of the Chardonnay and the Riesling Renano grapevines, since the beginning of the bud break until harvest is derived of different forms of N from those applied in the bud break. The highest quantity of N accumulated in the annual and perennial part of the...