Eficiência agronômica da ureia estabilizada com inibidores de urease e nitrificação na cultura do milho

Nitrogen (N) is the most required nutrient for corn plants and, in order to supply this demand in highly productive crops, mineral fertilizers are used, especially urea. The disadvantage of urea is the loss of N-NH3 to atmosphere. To reverse this situation, some technologies have been developed, such as nitrification and urease inhibitors, which are used as additives to urea. This work aimed at evaluating the agronomic efficiency of urea stabilized with urease and nitrification inhibitors applied to cover the 2013/2014 corn crop. We evaluated 11 nitrogen fertilizer applied in coverage: urea + PA (41.6% N, 3% Cu); urea + PA (41.6% N, 1.5% Cu); urea + PA (41.6% N, 3% Zn); urea + PA (41.6% N, 1.5% Zn); urea + PA (41.6% N, 0.34% Cu, 0.94% B); urea + PA (41.6% N, 0.25% Cu, 0.68% B); urea + PA (41.6% N); urea (44.3% N, 0.15% Cu, 0.4% B); urea (43% N, 0.1% Cu, 0.3% B, 0.05% Mo); pearled urea (46% N); urea + 0,8% DMPP (45% N) and the control, which did not receive nitrogen topdressing. The evaluations were: Nitrogen losses through volatilization, content and accumulation of N, boron (B), copper (Cu) and zinc (Zn) to the dry matter of aerial parts, grains, and in straw and grain productivity. Fertilizers stabilized with urease and nitrification inhibitors did not reduce the volatilization of ammonia volatilization, when compared to pearled urea. Urea with 0.8% of DMPP nitrification inhibitor (3,4-dimethylpyrazole phosphate) provided higher loss by volatilization, lower productivity and agronomic efficiency compared to pearled urea. The coating of urea with Cu, B and Zn did not increase the accumulation of these nutrients in grains and MSPA plants. The use of fertilizers stabilized and coated with micronutrients did not increase the productivity and agronomic efficiency compared to conventional urea.

Capacidade combinatória de linhagens e seleção de híbridos de sorgo sacarino

Sweet sorghum figure as an alternative feedstock for ethanol production. The establishment of this culture in Brazilian production chain depends on the development of more productive and adapted cultivars. The aim of this study was to evaluate the general combining ability (GCA) of sweet sorghum lines and specific combining ability (SCA) of hybrid combinations as the agronomic and technological traits, and additionally to identify promising hybrid combinations for evaluation in advanced trials. Five restorer lines (R) and four male-sterile lines (A) were used in a partial cross diallel yielding 20 hybrids. The parental lines, hybrids and one check were evaluated in experiments carried out in a rectangular lattice design 5x6 with three replicates in two locations. The following traits were measured: flowering time, plant height, green mass yield, dry matter percentage, dry matter yield, juice extraction, total soluble solids content, sucrose content, purity, reducing sugars content, fiber content, sugars reducing total content, total recoverable sugars, hydrous ethanol, tons of per hectare, and ethanol production. There were differences between locations and genotypes for the traits. There was a significant effect of the genotype by environment interaction for most characters, except juice extraction, purity and reducing sugars content. There were a significant effect of GCA and SCA for most traits, indicating that additive and non-additive effects affect the phenotypic expression. Considering the effects of the GCA, the A line 201402B022-A, and R lines BRS 511, CMSXS643, and CMSXS646 were considered promising for exploration as parents in breeding programs of sweet sorghum in order to increase the ethanol production and the quality of the feedstock.The hybrids 201402B010-A x BRS 511, 201402B010-A x BRS 508, 201402B010-A x CMSXS646, 201402B022-A x BRS 511, 201402B022-A x CMSXS643, 201402B022-A x CMSXS646, 201402B022-A x CMSXS647 were the most promising for ethanol yield.

Arginina para matrizes suínas primíparas em lactação

With the emergence of new genetic lines due to intense breeding improvement on swine production in recent years, there is the need to adapt more accurately diets for the current sows, which have higher nutritional demands. The use of functional amino acids aimsto optimize the sows production and among these amino acids arginine has excelled. Arginine is involved in several important metabolic pathways, for example, it serves as a substrate forsynthesis of protein, creatine, nitric oxide, polyamines, citrulline, agmatine, ornithine, proline, and glutamate. It also helps to stimulate the secretion of some hormones such as insulin, prolactin, and growth hormone.As arginine plays such important roles, its supplementation has been suggested in lactation feed once it may enhance the development of the mammary gland and milk nutritional profile, thus, providing a better piglet development.Thus, the objective was to evaluate the effect of lactation feed supplementation with L-Arginine on the productive performance of primiparoussows and their respective litter.One hundred forty sows from the same genetic lineage on a commercial farm, located in the city of Oliveira, MG were used in this study, in a completely randomized design with five treatments: control diet without amino acid supplementation and four diets with increasing levels of L-Arginine supplementation (containing 98.5% purity) - 0.5, 1.0, 1.5, and 2.0%. Each treatment hadtwenty-eight swine sows, and the experimental unit was the sowand its litter.It was used ‘on top’ amino acid supplementation.All data was submitted to variance analysis using the SAEG Software: version 9.1 (SAEG, 2005).The data relating to days of lactation were compared by Tukey test (5%). L-Arginine supplementation levels in lactation feed did not influence (P>0.05) average daily feed intake, body condition variables, and blood parameters of the sows (urea, creatinine, and non-esterified fatty acids) as well as it did not affect the dry matter, crude protein, and amino acid profile of milk and the litter performance. There was effect (P<0.05) of days of lactation on the percentage of crude protein and amino acids in milk, which reduced througout the days of lactation. The L-Arginine supplementation on the lactation diet at levels of 0.5, 1.0, 1.5, and 2.0% did not influence the sow and its respective litter performance.