ABSTRACT The objective of this study was to determine the effect of Azospirillum brasilense inoculation and different nitrogen (N) rates applied as topdressing on the productivity of a maize crop and the nutritional value of maize silage. Two experiments were conducted in the 2012/2013 and 2013/2014 harvests. Treatments were distributed in a randomized block design in a factorial arrangement, which consisted of two maize hybrids (AS 1572 and Defender) coupled with nitrogen rates (0, 60, 120, 240, and 480 kg ha-1), inoculated or uninoculated with A. brasilense. Inoculated seeds were treated with the A. brasilense strains Ab-V5 and Ab-V6. Inoculation with A. brasilense showed interaction with the hybrids, agricultural years, and nitrogen rates for the maize plant yield. In the 2012/2013 agricultural year, inoculation increased the AS 1572 hybrid silage yield by 6.16% and, in the 2013/2014 harvest, A. brasilense inoculation produced an increase of 16.15% for the Defender hybrid. Nitrogen fertilization applied at 0, 60, and 120 kg ha-1 N benefited the plants inoculated with A. brasilense. The statistical equations revealed that N rates between 0 and 184 kg ha-1 in A. brasilense inoculated plants raised the plant productivity for silage when compared with the control plants. Regarding the nutritional value of the silage, inoculation with A. brasilense increased the ether extract levels and total digestible nutrients and reduced the amount of acid detergent fiber. For all this, positive results with inoculation for silage yield are dependent on nitrogen fertilization rate. Inoculation with A. brasilense can promote changes in the maize silage quality, but with obtained results it is not possible to definitely conclude upon nutritive value of maize silage.

This experiment was carried out to evaluate the effects of the row spacing between corn plants on silage quality. Different spacing between corn rows (40, 60, and 80 cm) was used, but the population of plants was maintained around 65,000/ha in all treatments. Analysis of variance was carried out and means were compared by Tukey's test at 5% of probability. A reduction in row spacing provided better spatial distribution of plants, but did not alter morphological composition or dry matter production. The corn with most equidistant spatial distribution (lowest row spacing) showed an increase in lignin concentration, neutral detergent fiber, and total carbohydrates, and showed a decrease in total digestible nutrients when compared with 80 cm row spacing. However, the organic digestibility matter was not affected by the treatments. The content and quality of protein were higher for 80 cm row spacing compared with the other levels; also, protein content was reduced as the spacing between rows became smaller. The only mineral affected was calcium, which had the lowest value at higher levels of spacing. Although differences were detected for many variables, the most appropriate spacing between rows should also take into account economic and practical aspects when choosing the best plant arrangement.

O trabalho objetivou avaliar a dinâmica do nitrogênio (N) no azevém consorciado com diferentes espécies forrageiras, em função do acúmulo de matéria seca (MS), em um sistema de transição agroecológica. Foram avaliados os consórcios de azevém anual cv. Comum, com aveia preta (AZ + AV), trevo branco (AZ + TB) e amendoim forrageiro (AZ + AF). O delineamento experimental foi o inteiramente casualizado, com três repetições. Utilizou-se o modelo de diluição do N no tecido vegetal, o qual utiliza comparativamente os fatores modificáveis do meio ambiente em um nível ótimo. O modelo descreve o declínio da concentração do N em função do acúmulo de forragem de pastagens temperadas. Os dados de campo foram confrontados ao modelo utilizando-se a análise do desvio da raiz do quadrado médio. O valor do coeficiente de diluição (β) em todas as pastagens foi inferior a -0,60. O declínio mais intenso da concentração de N no tecido vegetal em função do acúmulo de MS ocorreu na pastagem de AZ + TB (β = -0,94), seguido das pastagens de AZ + AF (β = -0,86) e AZ + AV (β = -0,67), respectivamente. O azevém consorciado com trevo branco apresentou maior conteúdo de N no tecido vegetal, com índice de nutrição nitrogenada mais próxima ao modelo estudado.

The dynamics of nitrogen (N) in ryegrass intercropped with different forage species with regard to dry matter (DM) accumulation within an agroecological transition system was evaluated. Annual ryegrass was intercropped with black oats (RY + BO), white clover (RY + WC) and forage peanut (RY + FP). The experimental design was completely randomized, with three replications. The study applied the N dilution model for plant tissue which comparatively uses modifiable factors of the environment at optimal levels. The model shows decline in N concentration due to the DM accumulation of temperate grass pastures. Data were compared to model by the root mean square deviation analysis. Dilution coefficient (β), used in all pasture samples, was lower than -0.60. Highest N concentration decline in plant tissues, due to DM accumulation, occurred in RY + WC pastures (β = -0.94), followed by RY + FP (β = - 0.86) and RY + BO (β = - 0.67), respectively. Ryegrass intercropped with white clover showed the highest N content in plant tissue, with a nitrogen nutrition index close to the proposed model.

Neste trabalho objetivou-se avaliar a influência de espécies em consórcio com azevém sobre a composição botânica e estrutural e o valor nutritivo dos pastos em um sistema de transição agroecológica. Foi avaliada a cultura do azevém (Lolium multiflorum Lam.) consorciada com aveia-preta (Avena strigosa Schreb.), trevo-branco (Trifolium repens L.) e amendoim-forrageiro (Arachis pintoi Krapov. & Gregory). O delineamento experimental foi o inteiramente casualizado, com três tratamentos e três repetições. O primeiro pastejo foi realizado 21 dias após a emergência das plantas nas pastagens de azevém + aveia-preta e azevém + amendoim-forrageiro e 28 dias após a emergência na pastagem de azevém + trevo-branco. O segundo pastejo na pastagem de azevém + aveia-preta ocorreu 30 dias após o primeiro pastejo, enquanto nas demais pastagens ocorreu 37 dias depois. As taxas de acúmulo de matéria seca (MS) do início do período de exclusão até o pico de produção de MS foram de 77,7; 75,0 e 71,3 kg/ha/dia de MS para as pastagens consorciadas com trevo-branco, amendoim-forrageiro e aveia-preta, respectivamente. A razão folha/colmo até o segundo pastejo foi elevada em todas as pastagens. A redução dos teores de PB conforme os dias de exclusão no pasto de azevém + aveia-preta é menor que nos pastos de azevém consorciado com trevo-branco ou amendoim-forrageiro.

The objective of this work was to evaluate the influence of species intercropped with ryegrass on the botanical and structural composition and the nutritional values of pastures in an agroecological transition system. It was evaluated ryegrass (Lolium multiflorum Lam.) intercropped with black oats (Avena strigosa Schreb.), white clover (Trifolium repens L.) and forage peanut (Arachis pintoi Krapov. & Gregory). It was used a complete random design with three treatments and three repetitions. The first grazing was done 21 days after emergence of the plants on the pastures with ryegrass and black oats and ryegrass and forage peanuts and 28 days after emergence on the pasture of ryegrass + white clover. The second grazing, on the pasture with ryegras + black oats, occurred 30 days after the first one, whereas on the other pastures, grazing occurred 37 days later. The rates of dry matter (DM) accumulation, from the beginning of period of exclusion until maximal production of dry matter were: 77.7; 75.0 and 71.3 kg/ha/day of DM for the pastures intercropped with white clover, forage peanut and black cover, respectively. Leaf/culm ratio until second grazing, was high on all pastures. Reduction on contents of crude protein according to exclusion days on ryegrass + black oat pasture is lower than on pastures of ryegrass intercropped with white clover or forage peanut.

Avaliaram- se a produção das culturas, a qualidade fermentativa e o valor nutricional da silagem de cultivares de aveia- branca (Avena Sativa L.) e aveia- preta (Avena Strigosa Schreb) submetidas ao corte em dois estádios de maturação. O delineamento experimental foi de blocos ao acaso, num arranjo fatorial 4 x 2, composto por quatro cultivares de aveia (dois de aveia- preta: Comum e UTFP 971; e dois de aveia- branca: ER 91156- 121 e SI 98105- b), com quatro repetições. Os cultivares foram ensilados nos estádios de floração e grão pastoso. O corte da aveia no estádio de grão pastoso, sobretudo dos genótipos de aveia- branca, possibilita obter silagem de maior qualidade, tanto produtiva quanto qualitativa. O cultivar, o genótipo e o estádio de maturação influenciam o fracionamento das proteínas e dos carboidratos de silagens de aveia.

It was evaluated in this work, crop yield, fermentative quality and nutritional value of the silage of cultivars of white (Avena Sativa L.) and black (Avena Strigosa Schreb) oats cut at two development stages. It was used an experimental randomized block design in a 4 x 2 factorial scheme, consisting of four oat cultivars (two cultivars of black oats: Aveia Preta Comum and UTFP 971; and two cultivars of white oats: ER 91156- 1- 2- 1 and SI 98105- b), with four replicates. The cultivars were ensiled at flowering and dough grain stages. Oat cut at dough grain stage, especially genotypes from white oat, allows the obtainment of a more productive and qualitative silage. Cultivar, genotype, and maturation stage affect protein fractioning and oat silage carbohydrates.

O objetivo nesta pesquisa foi avaliar a produção de forragem e a carga animal de quatro pastagens: Coastcross (Cynodon dactylon L. Pers.) sobressemeada com azevém (Lolium multiflorum Lam. cv. Comum); Coastcross sobressemeada com azevém e trevo-branco (Trifolium repens L., cv. Yi); azevém e trevo branco; e azevém. O experimento foi realizado no período entre 15 de maio e 24 de outubro de 2006, quando foram realizados cinco ciclos de pastejo. Utilizaram-se vacas da raça Holandesa recebendo concentrado (3,5 kg/dia) como suplemento alimentar. Nos períodos pré e pós-pastejo, foram avaliadas a massa de forragem, as composições botânica e estrutural da pastagem e a carga animal. O delineamento experimental foi inteiramente casualizado com quatro tratamentos (pastagens), duas repetições (piquetes) e cinco períodos de avaliação (pastejos). Não foram detectadas diferenças entre pastagens para as médias de massa de forragem e carga animal. As pastagens exclusivamente de azevém tiveram maiores produções de lâminas foliares de azevém. As pastagens sobressemeadas apresentaram maior produção de forragem. A sobressemeadura do azevém e do trevo-branco em Coastcross permite estender o período de utilização da pastagem anual e aumenta a produção de forragem.

The objective of this research was to evaluate the forage production and stocking rate (SR) of four Coastcross (Cynodon dactylon L. Pers.) pastures overseeded with ryegrass (Lolium multiflorum Lam. cv. Common); ryegrass plus white clover (Trifolium repens L., cv. Yi) over bermudagrass; ryegrass plus white clover and ryegrass. The experiment was carried out from May 15 to October 24, 2006, in five grazing periods. Holstein cows receiving 3.5 kg/daily complementary concentrate feed were used in the evaluation. In the pre and post grazing periods, the forage mass, botanical and structural pasture composition and the stocking rate were assessed. A randomized complete design was used, with four treatments (pastures) and two replications (paddocks), in five grazing cycles. No differences in herbage mass and stocking rate averages were detected among pastures. The ryegrass pastures had larger ryegrass leaf blade herbage mass production. The overseeded pastures had larger forage production. Overseeding with ryegrass and white clover on Coastcross extend the use period of annual grass and increase forage production.

Este trabalho teve por objetivo avaliar os parâmetros microbiológicos e físico-químicos do grão de soja (Glycine max L.) desativado, tratado com três diferentes dosagens (2, 4 e 6L t-1) de uma mistura de ácidos orgânicos e seus sais (AOS), com a função de aditivo antifúngico. O ensaio teve uma duração de 90 dias, em que foram feitas a contagem de bolores e leveduras (UFC g-1), e a identificação dos gêneros fúngicos, da umidade (U), da atividade de água (AA), do índice de peróxido (IP) e do índice de acidez (IA). As análises foram realizadas em triplicata, em intervalos de 15 dias entre cada análise, até o 60o dia de avaliação e depois no 90o dia do experimento. Verificou-se aumento na UFC g-1 nas doses de 2 e 4L t-1, bem como mudança nos gêneros fúngicos encontradas nestes tratamentos a cada avaliação, diferentemente da baixa UFC g-1 e da identificação de gêneros na dose de 6L t-1. Os valores de U e AA mantiveram-se acima dos padrões recomendados de 14% e 0,70, respectivamente em todos os tratamentos e avaliações. O IP aumentou significativamente a partir do 45o dia de avaliação no controle e a partir do 60o dia nos demais tratamentos. O IA não variou significativamente durante o período de avaliação. Conclui-se que a dosagem de 6L t-1 foi eficiente na proteção antifúngica desta matéria-prima.

This research had the objective to evaluate microbiological and physical-chemical parameters of deactivated soybean grain (Glycine max L.) treated with three different dosages (2, 4 and 6L t-1) of organic acids and their salts mixture (AOS), as an antifungical additive. The assay had a duration of 90 days, where executed fungi count (UFC g-1), fungi specie identification, humidity (U), activity of water (AA), peroxide value (IP) and acidity value (IA). The analyses were carried out in triplicate, in intervals of 15 days among analysis, until 60th day of evaluation and, at the 90th day of evaluation. There were increases in the UFC g-1 in dosages of 2 and 4L t-1, as well a change in fungi species found in these treatment at each evaluation, distinguished of low UFC g-1 and fungi species in dosage of 6L t-1. The values of U and AA were above of recommended patterns of 14% and 0.70, respectively for all treatments and evaluations. The IP increased significative from 45th day of evaluation in control and from 60th day in other treatments. The IA had no significative variation during the period of evaluation. The dosage of 6L t-1 was efficient in the antifungical protection of this raw material.