Índices de crescimento e componentes da produção do milho e soja em sistemas agrossilvipastoris.

Orientador: Prof. Dr. JOADIL GONÇALVES DE ABREU; Co-orientador: Dr. ROBERTO GIOLO DE ALMEID

Silagem de milho safrinha com níveis crescentes de forragem de guandu.

Resumo: Objetivou-se avaliar o efeito de níveis crescentes de adição de guandu na composição bromatológica da silagem de milho safrinha. Utilizou-se delineamento inteiramente casualizado, com quatro repetições. O corte das forrageiras para ensilagem foi realizado a 20 cm do nível do solo. Os silos experimentais utilizados eram de PVC com 10 cm de diâmetro e 50 cm de comprimento, com capacidade para 2,50 kg de silagem (600 kg m-3 ). As silagens foram analisadas quanto às variáveis: pH, proteína bruta (PB), FDA e NDT. Os resultados demonstram que para os quatro níveis de adição de guandu (10%, 20%, 30% e 40%) na silagem de milho, o pH ficou dentro da faixa adequada, de 3,8 a 4,2. O teor de PB variou de 9,05% a 15,08%, do nível 0 a 40% de inclusão de guandu na silagem de milho. Para FDA e NDT, o nível de 10% de inclusão de guandu proporciona silagem semelhante à de milho puro. A inclusão de forragem de guandu até o nível de 20% é uma alternativa indicada para a melhoria do valor nutritivo da silagem de milho. [Maize silage with increasing proportions of Cajanus cajan cv. Mandarim forage] Abstract: Goal of the work was to evaluate the effect of different proportions of added Cajanus cajan cv. Mandarim forage over nutritional composition of inter-seasonal maize silage (in Brazil called . Experimental design was random blocks with four repetitions. Plants for silage were harvested 20 cm above soil. Experimental silos were PVC tubes with 10 cm diameter and 50 cm lenght, bearing 2.50 kg silage which (600 kg m-3 ). Variables analized were: pH, crude protein (CP), ADF and TDN. Results showed that for the four Cajanus addition levels (10%, 20%, 30% and 40%) in the maize silage, pH kept within normal range (3.8 to 4.2). PB content varied from 9.05% to 15.08%, from 0 to 40% Cajanus proportion in the silage. For ADF and TDN, 10% Cajanus inclusion level resulted in silage similar to plain maize, while above 20% silage quality might be compromised. Therefore, inclusion of up to 20% Cajanus forage showed to be a recommendable alternative to improve maize silage nutritional valu

Production and nutritive value of piatã grass and hybrid sorghum at different cutting ages.

The influence of cutting age on production and nutritive value of piatã grass (Brachiaria brizantha cv. BRS Piatã) and hybrid sorghum (Sorghum spp. cv. BRS 801) under an integrated croplivestock system was evaluated. The trial was carried out at the Embrapa Beef Cattle (20º27' S; 54º37' W) in Campo Grande, Mato Grosso do Sul State, Brazil, between April and October 2009. Experimental design consisted of randomized blocks with four replicates. Treatments were distributed across a split-plot design, which included three production systems (single piatã grass; single hybrid sorghum; mixed cultivation of sorghum and piatã grass). Half-plots consisted of three forage ages at harvest (with 70, 90 and 110 days after seeding). Variables included agronomical characteristics, productivity and nutrition value. Regardless of the evaluated systems, cutting age affected agronomical characteristics and in vitro digestibility of organic matter (IVDOM). Production was highest (4,048 kg ha-1) within the integrated system. Regardless of cutting age, monoculture sorghum had the highest crude protein level. Results showed that integrated sorghum and piatã grasses were an asset for forage productivity. Forages had higher values in crude protein and in in vitro digestibility of organic matter on the 70th day after seeding.Título em português: Produtividade e valor nutritivo de capim-piatã e sorgo de corte e pastejo em diferentes idades de corte

Agronomic, economic and energy performance of cassava genotypes in the southwestern Amazon region.

Cassava is an important crop in many parts of the world. It is a staple food for millions of people, and it is also used in a variety of other applications. Cassava is a rich source of carbohydrates and can be used to produce fuel-grade ethanol. The purpose of this study was to evaluate the agronomic, economic, and energy performance of several cassava genotypes in the southwest region of the Brazilian Amazon. Root productivity, flour yield, dry mass, starch content, number of roots per plant, number of rotten roots per plant, plant and first branch height, gross and net costs and income, and the crop's energy balance were evaluated. The genotypes affected all evaluated characteristics. The BRS Kiriris genotype excelled in terms of flour yields, root productivity, and absence of rot disease. The highest net revenues were observed for the most productive genotypes. The research disclosed an average energy demand of 9.78 GJ ha-1. BRS Kiriris (252,7 GJ ha-1) produced the most favorable energy balance, with an energy efficiency of 26.9. The greatest demand for direct energy costs for root production was for nitrogen fertilization (37,9%), followed by the use of herbicides (27,9%), which have a high energy charge associated with their manufacture. Cassava is a valuable source of biofuel feed in the Brazilian Amazon's southwest region. The selection of the appropriate cassava genotype is crucial for achieving adequate levels of activity sustainability

Benthic estuarine communities in Brazil: moving forward to long term studies to assess climate change impacts

Abstract Estuaries are unique coastal ecosystems that sustain and provide essential ecological services for mankind. Estuarine ecosystems include a variety of habitats with their own sediment-fauna dynamics, all of them globally undergoing alteration or threatened by human activities. Mangrove forests, saltmarshes, tidal flats and other confined estuarine systems are under increasing stress due to human activities leading to habitat and species loss. Combined changes in estuarine hydromorphology and in climate pose severe threats to estuarine ecosystems on a global scale. The ReBentos network is the first integrated attempt in Brazil to monitor estuarine changes in the long term to detect and assess the effects of global warming. This paper is an initial effort of ReBentos to review current knowledge on benthic estuarine ecology in Brazil. We herein present and synthesize all published work on Brazilian estuaries that has focused on the description of benthic communities and related ecological processes. We then use current data on Brazilian estuaries and present recommendations for future studies to address climate change effects, suggesting trends for possible future research and stressing the need for long-term datasets and international partnerships

Produtividade de milho em sistema de integração lavoura-pecuária-floresta

Comissão organizadora: Denise Baptaglin Montagner, Grácia Maria Soares Rosinha, Rodrigo Carvalho Alva