Asymmetrical Dependence Between a Neotropical Mistletoe and its Avian Seed Disperser

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Seed germination performances of Styrax species help understand their distribution in Cerrado areas in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ovule, fruit and seed development in Abolboda (Xyridaceae, Poales): implications for taxonomy and phylogeny

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

Frugivory and seed dispersal by tapirs: an insight on their ecological role

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Seed morphology of bladderworts: a survey on Utricularia sect. Foliosa and sect. Psyllosperma (Lentibulariaceae) with taxonomic implications

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Passion fruit seed meal at growing and finishing pig (30-90 kg) feeding

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

Tetrazolium test for assessment of seed viability of atemoya (Annona cherimola Mill. x A. squamosa L.)

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

Ecophysiology of seed germination in Digitaria insularis ((L.) Fedde)

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

Reconstructing past ecological networks: the reconfiguration of seed-dispersal interactions after megafaunal extinction

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

Different approaches on seed germination to look into global warming effects on Araucaria angustifolia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Rapid Assessment of Seed Removal and Frugivore Activity as a Tool for Monitoring the Health Status of Tropical Forests

Ecological processes in tropical forests are being affected at unprecedented rates by human activities. Yet, the continuity of ecological functions like seed dispersal is crucial for forest regeneration. It thus becomes increasingly urgent to be able to rapidly assess the health status of these processes in order to take appropriate management measures. We tested a method to rapidly evaluate seed removal rates on two animal-dispersed tree species, Virola kwatae and V.michelii (Myristicaceae), at three sites in French Guiana with increasing levels of anthropogenic disturbance. We counted fallen fruits, fruit valves, and seeds of each focal fruiting tree in a single 1m2 quadrat, and calculated two indices: the proportion of seeds removed and the proportion of fruits opened by mammals. They both provide an indirect and rapid assessment of frugivore activity. Our results showed a significant decrease in the proportion of removed seeds (16%) and fruits opened (19%) at the most impacted site in comparison with the other two sites (79% for seeds, 60% and 35% for fruits). This testifies to an increased impoverishment of the primate and toucan communities at the disturbed sites. This standardized protocol provides fast information about the health status of the community of seed dispersers and predators and of their seed removal services. It is time- and cost-effective and is not species-specific, allowing comparisons among sites or over time. We suggest using it with the pantropical Myristicaceae and any other capsule-producing family to rapidly assess the health status of seed removal processes across the tropics.

The community-level effect of light on germination timing in relation to seed mass: a source of regeneration niche differentiation

Within a community, species may germinate at different times so as to mitigate competition and to take advantage of different aspects of the seasonal environment (temporal niche differentiation). We illustrated a hypothesis of the combined effects of abiotic and biotic competitive factors on germination timing and the subsequent upscale effects on community assembly. We estimated the germination timing (GT) for 476 angiosperm species of the eastern Tibetan Plateau grasslands under two light treatments in the field: high (i.e. natural) light and low light. We also measured the shift in germination timing (SGT) across treatments for all species. Furthermore, we used phylogenetic comparative methods to test if GT and SGT were associated with seed mass, an important factor in competitive interactions. We found a significant positive correlation between GT and seed mass in both light treatments. Additionally, small seeds (early germinating seeds) tended to germinate later and large seeds (late germinating seeds) tended to germinate earlier under low light vs high light conditions. Low light availability can reduce temporal niche differentiation by increasing the overlap in germination time between small and large seeds. In turn, reduced temporal niche differentiation may increase competition in the process of community assembly.

FLUXOFENIM USED AS A SAFENER ON SORGHUM SEED FOR S-METOLACHLOR HERBICIDE

This study aimed to evaluate the efficiency of protective fluxofenim seed treatment of sorghum hybrids DKB510 and SCG340, in order to increase the selectivity to the herbicide S-metolachlor applied pre-emergence and to determine the activity of detoxification enzyme glutathione S-transferase (GST). This work was divided into two stages. The first step consisted of field evaluation of the effectiveness of the shield to reduce visual symptoms of plant injury caused by the herbicide and the second determined the activity of GST. It was compared the susceptibility of sorghum seeds to the herbicide by means of visual assessment of injuries at 3, 7, 15 and 30 days after emergence (DAE), root dry weight and shoot at 10 DAE, and determination of activity GST. The treatments were: application of the safener dose at 0 and 40 mL per 100 kg of seed, and spraying of the herbicide S-metolachlor at rates of 1,440 and 2,880 g a.i. ha(-1), and a control without herbicide. The safener use to seed treatment for both sorghum hybrids (DKB510 and SCG340) increased tolerance to the herbicide S-metolachlor in two doses, and the best results were obtained at a dose of 1,440 g ha(-1). The GST enzyme activity showed an increase when using the fluxofenim prior to application of the herbicide S-metolachlor at a dose of 1,440 g ha(-1) for the two hybrids.

Patch size, shape and edge distance influences seed predation in a keystone palm in tropical rainforests

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Avaliação da fermentação aeróbia para produção de etanol a partir da xilose por linhagem de leveduras isoladas da casca de uva (Vitis spp)

Isolate microorganisms that fermenting xylose to ethanol is a challenge to expand production of biofuels from lignocellulosic materials. For this work was tested fermentation of xylose by yeast strains isolated from grape skins (Vitis spp) in order to ethanol produce. The yeasts were grown in submerged fermentation with xylose as a carbohydrate source. Aliquots were taken every 24 hours to measure cell growth, sugar consumption and ethanol production. The yeast had an production ethanol average of 2.5 g / L and yield (Ye / s) 0.12 g / g, showing that they have the ability to produce ethanol from xylose.