Jailson Lara Fagundes

Respostas de genótipos de palma forrageira a diferentes densidades de cultivo

Considering the importance of cactus pear as an alimentary alternative for the herd of cattle of the Brazilian semiarid region and the effect of crop spacing among plants, this study aimed to evaluate the morphometry, yield and chemical-bromatological composition of cactus pear genotypes, under different cropping densities. The experimental design was completely randomized blocks, in a 3x4 factorial scheme. Treatments consisted of a combination of three cactus pear genotypes (Gigante, Redonda and Miuda) and four cropping densities (10,000 plants ha -1 ; 20,000 plants ha -1 ; 40,000 plants ha -1 ; and 80,000 plants ha -1 ), with three replications. The cactus pear genotypes reacted differently, regarding morphometry, yield and chemical-bromatological composition, and, regardless of the species, the denser planting increased yield (tons ha -1 ). The Miuda palm presented the highest dry matter yield and consequently the greater accumulation of total digestible nutrients, raw protein and water per hectare, as well as the highest in vitro dry matter digestibility.

Valor nutritivo da silagem de maniçoba ("Manihot pseudoglaziovii") com e sem fubá de milho como aditivo

O estudo foi conduzido com o objetivo de estudar o valor nutritivo da Manicoba sob a forma de silagem, com ou sem fuba de milho como aditivo. Os tratamentos utilizados foram: silagem de manicoba (SM) com quatro niveis (0; 10; 20 e 30%) de adicao de fuba de milho como aditivo, sendo cinco repeticoes por tratamento. O pH das silagens se manteve entre 4,1 e 4,3 tanto para silagens com e sem aditivo, indicando que ocorreu uma boa fermentacao lactica independente da adicao de fuba de milho. Para DIVMS ocorreram valores crescentes e significativos (P<0,05) a medida que houve aumento da adicao de fuba de milho, sendo que a inclusao de 20 % de fuba foi responsavel pelo maior valor deste parâmetro (65,1 %). As concentracoes de acido acetico e butirico foram reduzidas na medida em que foram adicionados niveis crescentes de aditivo. As concentracoes de acido lactico foram consideradas satisfatorias em todos os tratamentos. Ocorreu decrescimo significativo (p< 0,05) nos teores de FDN e FDA com a inclusao do fuba de milho, sendo encontrado o menor valor para o tratamento com 20 % de aditivo. Conclui-se que a silagem de manicoba e uma alternativa alimentar de bom valor nutricional, principalmente quando adicionado de fuba de milho como aditivo. O melhor nivel de inclusao de fuba de milho na silagem da manicoba e de 20%.

Brachiaria sp YIELD AND NUTRIENT CONTENTS AFTER NITROGEN AND SULPHUR FERTILIZATION

Among the production factors, adequate fertilization is an important tool to raise the productivity of pastoral systems and consequently increase the share of Brazil in the supply chain of primary agricultural products at the global level. The objective of this study was to evaluate the interaction of nitrogen and sulfur fertilization in BRACHIARIA DECUMBENS: Stapf. The experiment in pots with Dystrophic Oxisol was evaluated in a completely randomized design with four replications in a 5 x 3 factorial arrangement, involving five N doses (0, 100, 200, 400, and 800 mg dm-3) in the form of ammonium nitrate and three S doses (0, 20 and 80 mg dm-3) in the form of calcium sulfate, with a total of 15 treatments. In the treatments with low S dose, calcium was provided as calcium chloride, to ensure a homogeneous Ca supply in all treatments. The results showed that the tiller production and dry weight of green leaves and of stems + sheaths and total dry weight were favored by the combination of N and S fertilizer, while the proportion of dry leaves was reduced. Nitrogen fertilization raised the N contents in green leaves and stems + sheaths and reduced K contents in fresh and dry leaves. The response to S rates in the N content of green leaves was quadratic.

Nitrogen and carbohydrate fractions on Tifton-85 pastures overseeded with annual winter and summer forage species in different seasons

An experiment was conducted during the 2001-2002 winter-spring-summer to determine the nitrogen and carbohydrate fractions in Tifton-85 pastures exclusively or overseeded with oats, millet and sorghum-sudangrass hybrids. The treatments were Tifton-85 overseeded with millet + bristle oat; sorghum-sudangrass + bristle oat, on 06/19/2002 and 07/02/2002, respectively; and Tifton-85 (Control). The experiment was conducted in a randomized block design with three replications. Nitrogen and carbohydrate fractions were affected by the nitrogen and total carbohydrate contents observed in the pasture overseeded at different seeding times, and by the different growth periods. The highest nitrogen fractions (A + B1) were observed in the early growth periods. Overseeding affected the forage nitrogen and carbohydrate fraction contents positively. The high solubility of both carbohydrate and protein from millet + bristle oat and bristle oat + sorghum-sudangrass mixtures indicates the quality of these forages and their potential use as an important supplement in forage systems based on tropical pastures.

Morphogenetical, structural and access to productive buffel grass

O objetivo deste trabalho foi avaliar as caracteristicas morfogenicas, estruturais e produtivas de acessos de capim-buffel (Cenchrus ciliaris L.). O experimento foi realizado no Departamento de Tecnologia e Ciencias Sociais (DTCS) da Universidade do Estado da Bahia (UNEB), em Juazeiro-BA, no periodo de novembro de 2008 a janeiro de 2009. O delineamento experimental utilizado foi inteiramente casualizado com seis acessos de capim-buffel (Tanzânia, Pusa Giant, Aridus, Buchuma, Ira e Biloela) e cinco repeticoes, totalizando 30 unidades experimentais. Os acessos diferiram estatisticamente (P<0,05) na maior parte das variaveis analisadas, principalmente nas variaveis morfogenicas e estruturais. Entretanto essas diferencas morfogenicas e estruturais nao influenciaram nos parâmetros produtivos. Observou-se que o capim-buffel apresenta uma taxa de aparecimento media de uma folha a cada quatro dias em cada perfilho, com um tempo de vida da folha de 17 dias, mantendo dez folhas vivas por perfilho.