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Resistance of maize inbred lines to major leaf diseases should be characterized for the development of new hybrids in breeding programs. Thus, this study aimed to assess the severity of leaf diseases in maize inbredlines with different kernel hardnessand two sowingseasons. We assessed four inbred lines and one check hybrid with dent kernels and four inbred lines and a check hybrid with flint kernels. Treatments were conducted in two sowing seasons, one in October, and another in December 2013. The symptoms of gray leaf spot (Cercospora zeae-maydis), northern leaf blight (Exserohilum turcicum), and white leaf spot (a complex of Phaeosphaeria maydis and Pantoea ananatis) were assessed every 10 days from flowering. The area under the disease progress curve was also calculated. Severity level of the diseases was higher in inbred lines when compared to the check hybrds (AG8041 PRO and P30R50YH), regardless of kernel hardness. Dent-kernel inbred lines showed a higher severity of northern leaf blight symptoms when compared to flint-kernelones. It is worth mentioning that disease severity increased as sowing was delayed.

RESUMO - O experimento teve como objetivo avaliar a producao de biomassa, a composicao fisica e quimica da planta de milho para forragem. O delineamento experimental foi em blocos inteiramente casualizados com arranjo fatorial de tratamentos com esquema de parcelas subdivididas no tempo. O hibrido foi cultivado em cinco densidades de semeadura (80, 160, 240, 320 e 400 mil plantas ha-1) e colhido em cinco epocas (40, 50, 60, 70 e 80 dias apos a emergencia). Foram avaliados a composicao percentual das estruturas anatomicas da planta pela segmentacao dos componentes colmo e folhas e o potencial produtivo de biomassa verde e de biomassa seca (kg ha-1). O aumento da densidade populacional afetou a distribuicao dos componentes da materia seca total das folhas em detrimento do colmo. As variaveis avaliadas apresentaram diferenca significativa para o fator epoca de colheita, havendo diminuicao linear na relacao folha colmo (fo/co), teor de proteina bruta (% PB) e de minerais (cinzas) e aumento no teor de materia seca da planta inteira, folha e colmo (% MS), producao de materia seca total (kg de MS ha-1), teor de fibra em detergente neutro (% FDN), teor de fibra em detergente acido (% FDA) e dos nutrientes digestiveis totais (% NDT). O milho forragem apresenta-se como uma tecnica de grande potencial de producao de materia seca, fonte de fibra de alta qualidade para ruminantes com rapido ciclo de crescimento, independentemente da densidade testada, com possibilidade da manipulacao da composicao bromatologica em funcao da epoca de corte variando de 40 a 80 dias apos a emergencia. Palavras-chave: Zea mays L, composicao bromatologica, forragem, producao de biomassa. CORN FORRAGE PRODUCTION, CULTIVATED IN DIFFERENT PLANTING DENSITIES ABSTRACT - The experiment has the objective to evaluate biomass production and the physical and chemical of plant composition, as forage. The experimental design was randomized complete block split plot. The hybrid was grown in five seeding densities (80; 160; 240; 320 and 400 thousand plants ha-1) and harvested in five times (40, 50, 60, 70 and 80 days after emergence). The anatomical structure composition by segmentation of stem and leaf and the productive potential of biomass produce were evaluated. The increase in plant population affected the distribution of the components of total dry mass with an increase in leaf against the stem. All measured response variables showed a significant difference to the harvest time factor, with linear decrease proportion between leaf and stem (fo/co), crude protein (%CP), and minerals (ash) and increase of dry matter in biomass, leaf and stem (%DM), total production of nature matter (kg of MN ha-1), total production of dry matter (kg of MS ha-1), neutral detergent fiber (%NDF), acid detergent fiber (%ADF) and total digestible nutrients (%TDN). The forage corn can be a technique of great potential dry matter production, highly fiber quality for ruminants, rapid growth cycle, regardless of tested density, with possibility of manipulation of composition bromatological, according to the cutting time ranging from 40 to 80 days after emergence. Keywords: Zea mays L, bromatological composition, forage, biomass production.

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.

The aim of this study was to evaluate the effect of inclusion of probiotic Saccharomyces cerevisiae based on carcass characteristics of Holstein steers finished in feedlot. The experiment was conducted at the Midwest State University in the Center of Animal Production (NUPRAN). 24 Holstein steers were used with initial age of 192 days and initial body weight of 221 kg with a standard deviation of 7 kg. The experiment had a 210 days duration. The inclusion of probiotic containing the yeast Saccharomyces cerevisiae KA500 (2x1010 CFU g-1) was provided at the order of 10 g animal-1 day-1. At the end of the feedlot, following a fasting period of 12 hours, the animals were weighed before loading to the fridge. The slaughter followed the normal flow of a slaughterhouse. The probiotic containing live yeast resulted in no significant effect (p> 0.05) on the features and components that are not part of the carcass.

O experimento foi conduzido no Nucleo de Producao Animal (NUPRAN) da Universidade Estadual do Centro Oeste (UNICENTRO), com o objetivo de avaliar o efeito da colheita da planta de milho em diferentes estadios reprodutivos e com diferentes processamentos de graos sobre as perdas e o valor nutritivo das silagens. Diferencas (P