BRS Umbu Research Articles

Eficácia da piraclostrobina sobre a produção, a morfologia e o valor nutricional da forragem de cereais de inverno em cortes sucessivos

ABSTRACT This study aimed to evaluate the forage yield, morphology, and nutritional value of three winter cereal wheat (Triticum aestivum cv. BRS Umbu), white oats (Avena sativa cv. URS Guará), and black oats (Avena strigosa cv. Embrapa 139), harvested in two successive cuts, at the vegetative and full vegetative stages, applied or not with fungicide pyraclostrobin. Pyraclostrobin was sprayed two times during the vegetative stage, the first application at the phenological stage V5, and the second, 12 days after the first cut of each forage species. In general, the application of pyraclostrobin resulted in an increase in the participation of leaves in the plant structure, from 72.2% to 86.9% in the second cut; and crude protein increased, and lignin decreased (from 22.75% and 9.89% to 25.60% and 6.30%, respectively) in the first cut and (from 20.82% and 11.73% to 22.28% and 9.20%, respectively) in the second cut. Black and white oats had a higher cumulative biomass production, 3,698 kg ha-1, and 3,277kg ha-1, respectively, and white oats had the lowest content of acid detergent fiber (27.90%) at the second cut.

Technological Quality of Dual-purpose Wheat Stored

Defoliation may interfere in the sink-source relationship and influence the technological quality of wheat flour. This study aimed to confirm the effects of plant cutting heights and number of cuttings on the technological wheat flour quality of BRS Umbu and BRS Tarumã cultivars after six months of storage. A completely randomized design was used and treatments consisted of a combination of cutting heights (20 and 30 cm) and number of cuttings (no cutting, 1, 2 and 3 cuttings), resulting in the following treatments: 20/1, 20/2, 20/3 30/1, 30/2, 30/3 and controls with no cuttings. Grain moisture, crude protein, hectoliter weight, gluten strength, falling number and wet gluten were determined. It was observed the behavior for both cultivars and number of cuts was similar, and it was found that the defoliation height of 30 cm resulted in greater decreases in PH and W values of 2.5 and 25.5% respectively. The results indicate that defoliation does not lead to the evolution of the stored wheat evaluated technological properties and with storage, properties such as W and WG of both cultivars showed a reduction.

Influência do regime de cortes sobre a produção e valor nutricional de trigo cv. BRS Umbu para forragem

A otimização do manejo de pastagens é essencial para que se obtenha níveis produtivos superiores, e os cereais de duplo propósito têm se destacado, podendo ser utilizado visando diferentes objetivos dentro da propriedade através de diversas estratégias de manejo. Objetivou-se avaliar a produção de biomassa e o valor nutricional da forragem do trigo (Triticum aestivum L. cv. BRS Umbu) sob influência de regime de cortes sucessivos simulando situações de pastejo. O delineamento experimental utilizado foi em blocos ao acaso, composto por três tratamentos (sem corte - controle; um corte realizado; e dois cortes realizados) com cinco repetições. Para produção de biomassa seca acumulada foram observados valores médios de 10.926 kg ha-1 para o tratamento sem corte, 7.989 kg ha-1 para o tratamento com um corte e 3.514 kg ha-1 para o tratamento com dois cortes. Houve diferença entre a relação folha:colmo, sendo este fator reduzido de acordo com o aumento no número de cortes (4,14; 2,36 e 2,24 para os sistemas sem corte, com um e com dois cortes, respectivamente). Na composição bromatológica não foram encontradas diferenças significativas para os teores de proteína bruta, fibra em detergente ácido e fibra em detergente neutro. O aumento no número de cortes não reduz o rendimento de biomassa verde acumulado, mas, uma diminuição expressiva no percentual de folhas pode levar a menores produções de biomassa seca. Como a bromatologia não foi alterada pelo regime de cortes, percebe-se melhores resultados produtivos em sistema de um corte e/ou pastejo.

Sowing density and clipping management: effects on the architecture and yield of dual-purpose wheat

The dual-purpose wheat stands out as a complementary alternative for forage supply during the winter period. Therefore, this work had the objective of evaluate the performance characteristics in five genotypes of dual-purpose wheat submitted to different sowing densities and different clipping managements. The experiment was carried out during the 2016 and 2017 harvests. The experimental design was a randomized block design, organized in a factorial scheme, with five dual-purpose wheat genotypes (BRS Tarumã, BRS Umbu, BRS Figueira, BRS Guatambu and BRS 277) x five sowing densities (75, 150, 225, 300 and 375 seeds m²) x four clipping operations (zero, one, two and three clippings), arranged in three replicates. The measuring of characters were number of fertile tillers, seeds yield, angle of flag leaf, chlorophyll content and flowering. The genotype BRS Tarumâ is superior in number of fertile tillers and chlorophyll index for all the sowing densities, as well, the flowering is influenced direct by clipping managements. The sowing density of 75 seeds m-2 is not indicated for dual-purpose wheat independent of the clipping management. The seeds yield is amplified thought the increase in sowing density, however, advancing in clipping levels there is a decrease in forage yield.

Technological Quality of Dual-purpose Wheat Submitted to Successive Defoliations

Defoliation may interfere in the sink-source relationship and influence grain production and the respective technological quality of wheat flour, particularly in cultivars with potential as forage and in subsequent grain production. This study aimed to determine the effects of plant cutting heights and number of cuttings on the technological wheat flour quality of BRS Umbu and BRS Tarumã cultivars. A completely randomized design with four repetitions was used and treatments consisted of a combination of cutting heights (20 and 30 cm) and number of cuttings (no cutting, 1, 2 and 3 cuttings), resulting in the following treatments: 20/1, 20/2, 20/3 30/1, 30/2, 30/3 and controls with no cuttings. Hectoliter weight, grain crude protein, tenacity: extensibility ratio, gluten strength, falling number and wet gluten were measured. Regardless of the cutting height used, and after defoliation, the variables exhibited higher values than in non-defoliated plants, with protein content increasing by 6 and 11.3% for the BRS Tarumã and BRS Umbu cultivars, respectively. As such, it can be inferred that defoliation does not negatively affect the technological quality of wheat flour grown in a dual-purpose system.

Agronomic traits of dual-purpose wheat with different plant architectures under defoliation strategies

Crop-livestock system implies in the balance of appropriate animal foraging, minimizing effects on grain production on the same crop season. This study aims to assess canopy heights (20 and 30 cm) and cuts number (no cut, 1, 2 and 3 cuts) effects on wheat productivity and bromatological composition of forage, and grain yield of BRS Umbu and BRS Tarumã cultivars. Regardless cuts number and cultivars, 30 cm provided higher forage productivity (1032 and 1348 kg DM ha-1) than 20 cm (554 and 909 kg DM ha-1), for BRS Umbu and Tarumã, respectively, in average crop seasons. For both cultivars and crop seasons, mean values of 26% crude protein, 55% neutral detergent fiber and 26% acid detergent fiber were obtained. At 20 cm no difference in grain yield was observed as a function of cuts number with 3780 kg ha-1 for BRS Umbu, in average crop seasons and 4306 kg ha-1 in 2014, for BRS Tarumã. However, at 30 cm, the grain yield was penalized at least in 30% as a result only third cut. These results indicate that wheat as dual-purpose can be employed in southern Brazil in grazing systems in forage shortage times and then produce grains without yield penalties as a function to the management used.

Efficacy of pyraclostrobin on the production and chemical composition of forage and silage of wheat (Triticum aestivum cv. BRS Umbu) and oats (Avena strigosa cv. Embrapa 139) preceded by successive cuts in the hard dough grain stage

The objective of the experiment was to evaluate the productivity, nutritional value and degradability of forage and silage of wheat (Triticum aestivum cv. BRS Umbu) and black oats (Avena strigosa cv. Embrapa 139), preceded by successive cuts, harvested at the hard dough stage, subjected or not to treatment with pyraclostrobin fungicide. Plants were harvested manually with a height of 0.08 m from the ground surface, at the hard dough stage, after two cuts at the vegetative stage; two applications of pyraclostrobin, 0.6 L ha-1 were made, before the first and the second cut. Pyraclostobin decreased the dry matter losses from 21.1% of the control system to 7.7% for the system with pyraclostrobin, reduced the neutral detergent fiber from 70.05% to 66.73%, decreased detergent fiber acid from 43.37% to 39.96%, decreased lignin from 14.37% to 10.13% and increased the relative value of the food from 75.27% to 82.72%, all in the forage, which resulted in changes in silage, with a decrease in neutral detergent fiber from 64.00% to 58.46%, acid detergent fiber from 38.76% to 35.87%, lignin from 10.11% to 6.78% and an increase in the relative value of the food from 85.87 to 97.26. In the evaluation of the forages, wheat presented the best productivity, with 10,068 kg ha-1 vs. 8,238 kg ha-1 black oats, lower neutral detergent fiber (60.32% vs. 76.46%), lower acid detergent fiber (34.49% vs. 48.84%) and higher relative value of the food (96.04 vs. 61.95), these data were from the forage, which were reflected in the resulting silage. It is recommended to use pyraclostrobin as it reduces losses during fermentation, changes fiber composition and improves the degradability of the food. Among the forages, the wheat was more promising, than black oats, due to its productivity, combined with its better chemical composition and degradability.

Criteria for Decision Making and Economic Threshold Level for Wild Radish in Wheat Crop

ABSTRACT: Weed competition limits wheat yield by reducing the availability of essential resources for its growth and development. In this sense, this study aimed to estimate the economic threshold level (ETL) of wild radish (Raphanus raphanistrum) in competition with wheat cultivars. Treatments were arranged in a factorial scheme. The factor wheat cultivar consisted of early (BRS 328), medium (BRS 177), and late (BRS Umbu) cycles and the factor wild radish population ranged from 0 to 564 plants m-2 (10 populations) for the cultivar BRS 328, 0 to 472 plants m-2 for the cultivar BRS 177 (11 populations), and 0 to 724 plants m-2 for the cultivar BRS Umbu (10 populations). The early-cycle BRS 328 presented a higher competitive ability when compared to the medium-cycle BRS 177 and late-cycle BRS Umbu. Yield losses of wheat grains due to wild radish interference can be satisfactorily estimated by the rectangular hyperbola model using the variables plant population, shoot dry matter, soil cover, and leaf area of the weed. ETL values varied as a function of the cultivar cycle, being higher for the cultivar BRS 328 (early) > BRS 177 (medium) > BRS Umbu (late). Wild radish is competitive in wheat crop, requiring at least 1.6 plants m-2 for control to be justified.

Qualidade da silagem de trigo produzida sob níveis de adubação nitrogenada em dois estádios fenológicos

O objetivo do trabalho foi avaliar os efeitos de dois níveis de adubação nitrogenada em cobertura (88 kg ha-1 e 148 kg ha-1) na produção de silagem do trigo cultivar BRS Umbu, colhido em dois estádios fenológicos (pré-florescimento e grão farináceo). Foram avaliadas as produções de fitomassa fresca e seca, composição morfológica e bromatológica das silagens. O delineamento experimental foi de blocos ao acaso em esquema fatorial 2x2, sendo dois níveis de adubação nitrogenada em cobertura e dois estádios de colheita, com quatro repetições. Houve interação (p<0,05) entre os níveis de adubação nitrogenada e os estádios fenológicos de colheita para fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA) da silagem. O trigo cultivado com nível de 88 kg N ha-1 e colhido no estádio fenológico grão farináceo apresentou os menores teores de FDN (57,52%) e FDA (34,62%) comparativamente ao cultivo com nível de 148 kg N ha-1 no mesmo estádio de colheita. A colheita em pré-florescimento promoveu maior produção de fitomassa fresca (25.178 contra 20.646 kg ha-1), entretanto, houve maior produção de fitomassa seca no estádio de grão farináceo (9.792 contra 4.808 kg ha-1). Os teores de proteína bruta foram maiores na silagem colhida em estádio de pré-florescimento quando comparada a de grão farináceo, com 11,55 e 6,96%, respectivamente. Na avaliação conjunta dos resultados, é possível concluir que a silagem de trigo colhida em estádio de grão farináceo e com adubação nitrogenada de 88 kg ha-1 possibilitou os melhores resultados produtivos e nutricionais.

<b>Nutritional composition of pre-dried silage of different winter cereals

This study aimed to assess the chemical composition of the forage and pre-dried silage from twelve winter cereals harvested at pre-flowering. We used black oat (Avena strigosa) cv. EMB 139 and cv. IAPAR 61; white oat (Avena sativa) cv. IPR and 126 hp. URS Taura; barley (Hordeum vulgare) cv. BRS Brau and cv. BRS Cauê; wheat (Triticum aestivum) cv. BRS Umbu and cv. BRS Tarumã; rye (Secale cereale) cv. Temprano and cv. BRS Serrano; and triticale (X. Triticosecale) cv. IPR and 111 hp. BRS Saturno. Plants were harvested at pre-flowering, when they were pre-dried and ensiled. The analysis of variance evidenced nutritional differences between species and cultivars. Triticale cv. IPR 111 showed notorious chemical characteristics in relation to the other treatments, highest protein content (113.7 g kg-1) and lower content of NDF and ADF (657.9 and 380.9 g kg-1, respectively). Among the pre-dried silages, barley cv. BRS Cauê had the highest level of NDT (614.7 g kg-1). Triticale cv. IPR 111 was shown as a high-quality nutritional food as forage and kept these characteristics after conservation. On the other hand, the pre-dried silage of barley cv. BRS Cauê showed the highest potential for nutrient degradability.

PRODUTIVIDADE, QUALIDADE FISIOLÓGICA E RESÍDUO EM SEMENTES DE TRIGO EM FUNÇÃO DA DESSECAÇÃO COM HERBICIDAS

In the wheat crop,pre-harvest desiccation with herbicides caninfluencethe productivity and physiological seed quality.The study aimed to quantify the yield, physiological seed quality,andresidue in wheat seeds.The experimental design was a randomized block designina 2x2x6 factorial, being thefactor A constituting of wheat cultivars (BRS 177 e BRS Umbu),the factor B application stages (before and after physiological maturation) and, factor C desiccation with different herbicides (2,4-D, paraquat, glyphosate, ammonium glufosinate, metsulfuron-methyl, and control) with four replications.The variables analyzed were thethousand seedsweight, hectoliter weight, number of antheciumper spike, seed yield, physiological seed quality by the vigortestsand standard germination, and residue in wheat seeds after the application of herbicides in pre-harvest.The desiccation in pre-harvest herbicide held at a later stage after physiological maturity, in general, does not affect the physiological quality and seed yield of BRS Umbu and BRS 177 cultivars. The application of methyl-metsulfuronand paraquat does not show residual effects on the seed independent of the application stage, while the application of ammonium glufosinate, glyphosate, and 2,4-D,when applied before the physiological maturity result residue levels in wheat seed.

Adubação nitrogenada na produção de grãos e matéria seca de cultivares de trigo de duplo propósito

The dual-purpose wheat is intended to forage production and subsequently grain production. The objective was to evaluate BRS Taruma and BRS Umbu cultivars for forage mass production and grain yield under nitrogen (N) rates. The experiment was conducted in 2014, in experimental randomized blocks with split plot design, using two cultivars of dual-purpose wheat (BRS Umbu and BRS Taruma) and four nitrogen rates (0, 30, 60, and 120 kg N ha-1), adding a control (0 kg N ha-1),four replicates, the application was split. There was no interaction between cultivars and nitrogen rates. BRS Umbu cultivar was distinguished by plant height, ear length, number of grains per spike, and grain yield. In the dry mass production, the cultivars did not differ. There was linear and positive response with increasing N rates for all yield components and dry mass of forage. It was concluded that the N rate application up to 120 kg ha-1 provided the highest yield in all analyzed parameters, that in relation to yield components, as well as grain yield to BRS Umbu, stands out in relation to BRS Taruma.

Nutritional composition and aerobic stability of wheat and corn silages stored under different environmental conditions

We aimed to evaluate nutritional quality, fermentation profile, aerobic stability, and dry matter losses in corn (Zea mays) and wheat (Triticum aestivum 'BRS Umbu') silages. Treatments included uninoculated and inoculated (Lactobacillus plantarum and Pediococcus acidilactici, 1.0 × 105 UFC g-1) wheat silage, corn silage from a conventional hybrid and a transgenic hybrid. Nutritional quality and fermentation profile variables were tested in a completely randomized design. Means were compared using Tukey’s test at 5% significance. An aerobic stability trial was conducted in a factorial design with two silages (wheat × inoculated wheat; conventional hybrid corn × transgenic hybrid corn) and two temperatures (ambient temperature × controlled temperature at 24°C). Data were submitted to ANOVA and means were analyzed by the F test at 5% probability. Inoculation of wheat silage increased dry matter, organic matter, and total carbohydrates, but reduced crude protein by a dilution effect. Regarding the fermentation profile, inoculation reduced acetic acid and butyric acid content, whereas it increased propionic acid in wheat silage. Bt corn hybrid silage showed higher dry matter and lower neutral detergent fiber, whereas transgenic corn silage showed lower content of acetic acid, propionic acid, alcohol, and ammonia. Conversely, Bt hybrid silage showed higher butyric acid. Transgenic corn silage showed higher temperature than the conventional hybrid silage during aerobic exposure. Inoculated wheat silage experienced larger deterioration and dry matter losses during the aerobic stability trial. Temperature control worsened aerobic stability in all treatments, increasing dry matter losses and heating.

MÉTODO DE OBTENÇÃO DE MATÉRIA SECA E COMPOSIÇÃO QUÍMICA DE VOLUMOSOS

Resumo Objetivou-se avaliar a influência do método de secagem sobre a composição nutricional de diferentes volumosos. Foram utilizadas quatro gramíneas (Urochloa brizantha cv. Marandu, Urochloa brizantha cv. MG4, Cynodon dactylon cv. Coastcross e Panicum maximum cv. Áries), uma leguminosa forrageira, o estilosante (Stylosanthes cv. Campo Grande) e duas silagens (Zea mays e Triticum aestivum cv. BRS Umbu). Os métodos de secagem se basearam no uso da estufa de ventilação forçada e de forno de micro-ondas. O delineamento estatístico utilizado foi um arranjo fatorial 2 x 8 (2 métodos de secagem e 8 volumosos) com 4 repetições. O método de secagem não influenciou o conteúdo de matéria seca das forragens. A secagem em forno micro-ondas elevou os teores de fibra em detergente neutro nos volumosos avaliados. Houve interação entre o método de secagem e tipo de forragem avaliada, com relação à proteína bruta (estilosante), extrato etéreo (MG4, estilosante e Áries) e nitrogênio insolúvel em detergente neutro (Coastcross, MG4, Marandu e estilosante). O forno de micro-ondas pode ser utilizado como instrumento para obtenção da matéria seca em alimentos volumosos, porém, a técnica pode afetar a composição da forragem avaliada.

Fiber composition and degradability of cold season green forage and pre-dried silage harvested at pre-flowering

This study aimed to evaluate the contents of hemicellulose, cellulose, and lignin, as well as the rates of dry matter degradability in forage and pre-dried silage of different winter cereals harvested at pre-flowering. The experiment was conducted by the Animal Production Center (NUPRAN), Department of Agricultural and Environmental Sciences, State University of Midwest (UNICENTRO). It is located in Guarapuava – PR, Brazil. The study was part of the Master's Degree in Crop Production. As experimental materials, we used black oat (Avena strigosa) cv. EMB 139 and cv. IAPAR 61; white oat (Avena sativa) cv. IPR and 126 hp. URS Taura; barley (Hordeum vulgare) cv. BRS Brau and cv. BRS Cauê; wheat (Triticum aestivum) cv. BRS Umbu and cv. BRS Tarumã; rye (Secale cereale) cv. Temprano and cv. BRS Serrano; and triticale (X Triticosecale) cv. IPR and 111 hp. BRS Saturn. Dry matter degradability was measured by an in situ technique, arranged in a completely randomized block design with three replications (animal), subdivided in subplots. Treatments were the plots and subplots digestion times. The incubation times were 0, 6, 12, 24, and 48 hours. To that end, we used two 24-month rumen fistulated steers with 350 kg average weight. A similarity was observed in the results of both forage and pre-dried silage degradability, displaying the same trends. Barley cv. BRS Brau had the highest hemicellulose content in its composition; however, IPR 111 triticale was showed the highest degradability potential, both for green forage and pre-dried silage.

<b>Nutritional value of dual-purpose wheat genotypes pastures under grazing by dairy cows

In the south of Brazil, one of the major limitations to milk production is the low forage availability during autumn and early winter. The use of dual-purpose wheat genotypes is one alternative to minimize the impact of low forage availability in addition to produce grains. Therefore, this study aimed to evaluate the nutritional value of two dual-purpose wheat genotypes (BRS Tarumã and BRS Umbu). Structural composition and forage nitrogen uptake were evaluated. The nutritional value of the forage was analyzed for mineral matter (MM), organic matter (OM), neutral detergent fiber (NDF), crude protein (CP), total digestible nutrients (TDN), in situ organic matter digestibility (ISOMD) and in situ dry matter digestibility (ISDMD). Differences in NDF (49.03 vs. 46.44%), CP (24.4 vs. 27.4%), ISOMD (83.53 vs. 85.45%), ISDMD (83.59 vs. 86.65%) and TDN (75.37 vs. 78.39) for BRS Umbu and BRS Tarumã genotypes were detected, respectively. The BRS Umbu genotype had a lower leaf blade proportion and forage nitrogen uptake. The dual-purpose wheat genotype BRS Tarumã was superior in nutritive value.

Ecophysiological responses of dual-purpose wheat originating from different cutting management systems

Wheat is one of the most cultivated cereals worldwide. Some wheat genotypes may be used for dual purposes that is, in the production of animal fodder and grains. The objective of this study was to compare the growth, partitioning of assimilates, and seed vigor expression of dual-purpose wheat cultivars originating from seeds produced by plants subjected to different cutting management systems. Dual-purpose wheat seeds in the vegetative period were used for this study; these were obtained from the cultivar BRS Umbu produced by plants subjected to different cutting management systems. The experimental design was completely randomized in a factorial scheme, with four replications. The treatments comprised a combination of four seed production systems (one, two, and three cuts) and eight planting seasons (10, 20, 30, 40, 50, 60, 70, and 80 days after emergence [DAE]). Total dry-mass, dry-mass production rate, relative growth rate, net assimilation rate, leaf area index, solar energy conversion efficiency, dry-mass partitioning, seedling emergence in the field, and emergence speed index were evaluated. Data regarding seedling emergence and emergence speed index were adjusted by orthogonal polynomials. Primary growth data were evaluated from the simple logistic equation. From 60 DAE, an inversion of the values of total dry-mass was observed, and the maximum values were observed in plants from seeds produced without cutting management. The highest dry-mass production rates were noted for plants produced by seeds of plants not subjected to cutting management. The highest relative growth rates were noted among plants originating from seeds produced by plants subjected to three- and two-cut treatments. The net assimilation rate was higher in plants originating from seeds produced from plants subjected to cutting management systems. The highest values of emergence were observed for seeds obtained from the three-cut treatment. Similarly, an increase in the values of emergence speed index was observed in seeds from plants subjected to one-cut treatment. Dual-purpose wheat cultivars originating from seeds produced in the absence of cutting management presented higher total dry-mass, dry-mass production rate, and relative growth rate. The net assimilation rate was higher in plants from seeds produced with cutting management systems. Plants produced from seeds subjected to the three-cut production management resulted in more vigorous seeds.

Production and nutritional value of the wheat silage managed with different cutting systems

Winter cereals are mainly used for human and animal nutrition and several studies are now exploring their potential as conserved forage (hay and silage). Among the winter cereal species available for cultivation in the south of Brazil, which is major winter cereals producer in the country, the wheat cv. BRS Umbu has attracted special attention. However, few studies have investigated the potential of this cultivar for silage production. The aim of this study was to evaluate the production and quality of silage from the dual-purpose wheat, BRS Umbu, subjected to different cut managements treatments: T1 - without cut (control), T2 - one cut and T3 - two cuts. Each plot represented an experimental unit in a randomized block design, with 5 replicates per treatment. Two representative samples were collected from each plot to determine morphological segmentation (stem, leaf and ear) and dry matter (DM) content of the whole plant and its morphological components. At the time of opening of the silos, food chemical analysis and pH determination were performed. Forage mass production decreased by 26.88% and 67.82%, respectively, with one and two cuts, compared to control. The DM content of the ensiled plant was 49.9 g kg-1 for the control, 54.7 g kg-1 with one cut and 63.2 g kg-1 with two cuts, at the time of ensiling. Management cuts changed the morphological components of the plants, with a lower proportion of stem (28%) in plants subjected to two cuts. The control treatment showed fewer leaves in ensiled plant (9.6%) and intermediate amount of stalk (52.8%), and was significantly different (p < 0.05) to treatment of a cut. Regarding feed chemistry evaluations, no significant difference (p > 0.05) was observed for mineral matter (MM), crude protein (CP) and hemicellulose (HEM) between the different cutting regimens. However, neutral detergent fiber (NDF) and acid detergent fiber (ADF) decreased (p < 0.05) as the number of cuts increased. The control treatment showed higher NDF and ADF content (563.2 and 357.9 g kg-1 DM, respectively) and lower amount of total digestible nutrients (TDN) and net energy of lactation (NEL). However, the estimated milk production (EMP) was superior for this treatment (22,447 l ha-1), demonstrating the high impact of reduced forage mass production with increased number of cuts.

Physiological quality of dual-purpose wheat seeds from plants subjected to artificial defoliation

ABSTRACT: Defoliation may play a role in source-sink relationships and reduce the physiological quality of seeds. The main goal of this research was to investigate the effect of successive defoliations on physiological quality of wheat seeds in 'BRS Umbu' and 'BRS Tarumã' cultivars. Two experiments were carried out using a complete randomized design with four replications. Treatments included plants without defoliation (0), and those where 1, 2, and 3 consecutives defoliations were applied. Seeds from each treatment originated from four different lots. Data were analyzed with one-way analysis of variance and means compared by Tukey test at 5% statistical probability. Germination was not affected by defoliation, or the number of cuts, but an effect on vigor was reported.

DRY MATTER OBTAINIMENT METHOD AND CHEMICAL COMPOSITION OF ROUGHAGES

Abstract It was aimed determinate the influence of drying methods on nutritional composition of different roughages. The experimental material were four grass species (Urochloa brizantha cv. Marandu, Urochloa brizantha cv. MG4, Cynodon dactylon cv. Coastcross e Panicum maximum cv. Aries), one forage legume (Stylosanthes cv. Campo Grande) and two silages (Zea mays e Triticum aestivum cv. BRS Umbu). The drying methods were based on use of forced air oven or microwave oven. The experimental design were a 2 x 8 factorial arrangement (2 drying methods and 8 roughages) with 4 repetitions. There was no effect of drying method on roughages dry matter content. Microwave oven drying increased neutral detergent fiber. There was an interaction between drying method and evaluated roughage. Increased contents of crude protein (estilosante), neutral detergent insoluble nitrogen (Coastcross, MG4, Marandu e estilosante) and ether extract (MG4, estilosante e Aries) were observed when roughages were dried using microwave oven. The microwave oven usage is an alternative to obtain the dry matter content of roughages; however this technic may affect the sample composition.