Condição corpórea e hormônios de estresse como indicadores do status fisiológicos de três espécies de morcegos em resposta à fragmentação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Níveis de vitamina “e” em dietas de frangos sobre o desempenho, características da carcaça e da carne e resposta imune

Pós-graduação em Zootecnia - FMVZ

Papel do TLR-4 na resposta inflamatória e resistência à insulina no tecido adiposo em condições de sobrecarga nutricional crônica

Pós-graduação em Patologia - FMB

Desempenho de novilhos de corte em pastos de capim-tanzânia sob quatro alturas de desfolha

This study was carried out to evaluate the effects of four grazing heights under continuous stocking of Tanzânia grass (Panicum maximum Jacq. Cv. Tanzânia) on the stocking rate, performance and beef production per hectare. The experimental area was 12 hectares, divided into paddocks with one hectare each, with three replicates each (20, 40, 60 and 80 cm). There were three male Nellore bovines per paddock, adding animals as needed to adjust the desired heights in a completely randomized design. The stocking rate had a negative linear function of grazing heights in all seasons regarding yield per hectare, while the average daily gain showed opposite behavior. Apparently, Tanzânia grass heights between 40 and 60cm under continuous stocking enable good average daily weight gain in beef cattle, and high yield per hectare.

Características produtivas, morfogênicas e estruturais do capim Piatã submetido à adubação orgânica

The organic fertilizer can be a viable alternative in the production of forage grasses, however there is little information regarding doses and composition of the major organic fertilizers. The aim of this paper was to verify the influence of the different doses of organic compost produced from two types of poultry litter on the structural, morphogenetic and productive characteristics of Brachiaria brizantha cv 'Piatã'. The experiment was conducted in a greenhouse in a completely randomized design in a factorial scheme l with parcel subdivided in time. The parcels were composed by six treatments: two types of compost (poultry litter based in sugar cane and napier grass) in three doses (100, 200 and 300kg ha-1 equivalent N.) and the subparcels by the four different periods of cut. The composts were applied in a unique dose, after the uniformization cut, at the quantities: 11,36 and 11,83, 22,73 and 23,67, 34,09 and 35,50 g pot-1 for the poultry litter based in sugar cane and napier grass, respectively which are equivalent to the rates of 0, 100, 200 and 300kg ha-1 of N. The variables measured were: dry matter production (DMP), leaf appearance rate (LApR), phyllochron, leaf elongation dose (LER) and shoots elongation rate (SER), number of green leaves (NGL), final size of the leaf (FSL). No significant difference between the types of composts and in the interaction compost x doses was observed, thus, both could be used without the risk of loss in the use of the nutrients by the plants evaluated in the experiment. There was a significant difference between the DMP, LApR, phyllochron, LER, SER, NGL and FSL because of the increasing rates of nitrogen, followed by a linear model of prediction. The effect of the periods of slaughter was also observed, where the slaughters carried out in the summer presented a better performance over the morphogenetic and structural features evaluated.

Número e peso de perfilhos no pasto de capim-braquiária sob lotação contínua

The experiment was conducted to study the relationship between the number and weight of tiller categories in Brachiaria decumbens cv. Basilisk pasture managed under continuous stocking with cattle. The pasture was managed with an average height of about 25 cm. Plants of four different heights (10, 20, 30 and 40 cm) were evaluated by means of the randomized block design with two replications. The number of vegetative tillers, both live and total, reduced linearly according to the plant height. The number of reproductive tillers increased linearly according to pasture plant height (from 8 to 84 tillers m-2 when comparing plants 10 to 40 cm high). Vegetative and reproductive tiller weight increased linearly according to pasture plant height. Vegetative tiller weight (0.316 g average) was lower than the reproductive tiller weight (0.401 g average). A linear and negative relationship was found between the number and weight of the vegetative tillers, whereas a linear and positive one was found for the reproductive tillers. There are fewer vegetative tillers, and a greater number of reproductive and dead tillers in places with tall plants. At the places with high B. decumbens plants, tillers are heavier.

Defoliation patterns in signal grass tillers with varying heights in the same pasture

The experiment was carried out to evaluate the patterns of defoliation in plants of various heights in the same pasture of Brachiaria decumbens cv. Basilisk under continuous stocking with cattle. Four plant heights were evaluated (10, 20, 30 and 40 cm) in the same managed sward, with mean height equal to 25 cm. A randomized blocks design was used, with two replications. Defoliation frequency increased linearly along with plant height in the same pasture. Defoliation intensity, number of defoliations in leaf blade and percentage of leaf blade grazed per tiller also increased linearly along with plant height. The defoliation interval decreased linearly according to plant height. The quadratic model was adequately fitted into grazing efficiency data, reaching the highest value (98%) at the sward site with 35 cm plants. The percentage variation in signal grass height showed a negative linear response with initial plant height. The structure of the pasture, characterized by the diversity in plant heights, is simultaneously the cause and consequence of the variability in defoliation patterns in individual tillers, which occur on the horizontal plane of the pasture.

Translocação dos herbicidas glyphosate e imazamox em plantas de aguapé

Eichhornia crassipes is one of the main weeds found in aquatic environments, being undesirable for many activities. The aim of this study was to evaluate the translocation of glyphosate and imazamox in E. crassipes. Eight intervals were studied for cutting leaves that received herbicides: 2, 4, 6, 8, 12 and 24 hours after application (HAA), and a treatment with no cutting (untreated). The glyphosate dose was 2,160 g a.e. ha-1 (commercial product - Rodeo) + 0.5% v v-1 Aterbane adhesive spreader and imazamox at 290.4 g i.a. ha-1 (commercial product - Clearcast). The treatments were installed in a completely randomized design with four replications. Glyphosate showed a bad control for all the periods of leaf cutting. The imazamox did not provide control within 12 HAA, while from 24 HAA onward the control was effective. There was not a great mobility of the glyphosate molecule in water hyacinth plants, a period above 24 hours being needed for a satisfactory translocation. For imazamox at least 24 hours were needed after herbicide application for the translocation to occur along with subsequent control.

Emissão de CO2, características do dossel e acúmulo de forragem em pastos de capim-pensacola sob frequências de desfolhação

The aim of this study was to evaluate CO2 emission, canopy characteristics and herbage accumulation in pastures of pensacola bahiagrass under frequencies of defoliation. The experiment was conducted at the Universidade Estadual Paulista Julio de Mesquita Filho, Faculty of Agrarian Sciences and Veterinary of UNESP, Jaboticabal, São Paulo, Brasil. The experimental period was from May 3rd to July 26th 2012. The experimental area comprised 28 m² of pensacola bahiagrass (Paspalum notatum Flügge), divided into 10 plots for allocation of treatment (frequencies of defoliation = 2 or 4 weeks). The following variables were studied: canopy height, light interception, leaf area index, herbage accumulation, tiller density, CO2 emissions, soil temperature and moisture. The frequencies of defoliation in the months of May, June and July slightly affect pensacola bahiagrass characteristics. CO2, soil temperature and moisture are more associated to environmental conditions (months of evaluation) than to the frequencies of defoliation imposed to the canopies.

Evolução de CO2 e atividades enzimáticas em amostras de solo tratado com herbicidas

Effects of bentazon, metolachlor, trifluralin, imazethapyr, imazethapyr+lactofen, haloxyfop-methyl, glyphosate and chlorimuron-ethyl at rates of 2 and 10 times the equivalent commercial dose on soil microbial activity was evaluated in soil samples extracted from a field never treated before. Global soil microbe respiration, estimated by CO2 production at 2, 4, 8, 12, 16, 20, 24 and 28 days of soil incubation and enzymatic activities (dehydrogenase and fluorescein diacetate hydrolysis) at 8 and 28 days were used as bioindicators. Bentazon and mixture imazethapyr+lactofen at the highest rate and haloxyfop-methyl at both rates, inhibited soil respiration although with differences in timing and duration. None of the herbicides affected FDA hydrolysis. Dehydrogenase activity was inhibited at 8 days of incubation with bentazon and imazethapyr at high rates but it was stimulated by metolachlor and imazethapyr at low rate and glyphosate at the highest rate. Herbicide effects on soil microbial activity was detected with higher sensitivity by global soil microbe respiration and dehydrogenase activity than by FDA hydrolysis. Only dehydrogenase activity and soil respiration estimations at 8 days of soil incubation had significant correlation. Results indicated the need of multiple estimations when evaluating herbicides effects on soil microbiota

Molecular characterization of accessions of crabgrass (Digitaria nuda) and response to ametryn

Digitaria species are sugar cane crop weeds in Brazil and are being controlled with herbicides, although there are some reports of control failure, notably to the triazine group. Molecular techniques are recommended to analyze the genetic variability in weeds. RAPD (Random Amplified Polymorphic DNA), PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism) and, in combination with sequencing, allow the localization of resistance genes, as well as possible mutations related to the onset of resistant individuals in some species. Thus, the objective of this work was to characterize ten accessions of Digitaria spp. by RAPD and PCR-RFLP markers, to sequence a conserved region of the psbA gene and evaluate the accessions response to ametryn. As showed by molecular analysis there was high genetic similarity among the accessions, all of them presented similar genetics profiles and were susceptible to ametryn.

Fontes e doses de nitrogênio na cultura da Brachiaria brizantha cv. xaraés sob condições edafoclimáticas de cerrado

Pós-graduação em Agronomia - FEIS

Adubação nitrogenada e aplicação de herbicidas como reguladores de crescimento em grama esmeralda

Pós-graduação em Agronomia - FEIS

Biomarcadores cardioinflamatórios em repouso e o efeito do exercício físico aeróbio agudo na resposta glicêmica e do lactato sanguíneo em adultos diabéticos do tipo 1

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)