Redistribution of B-10 absorbed by leaves and roots of cashew seedlings

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

Community-wide spatial and temporal discordances of seed-seedling shadows in a tropical rainforest

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

In vivo assessment of genotoxic, antigenotoxic and anticarcinogenic activities of Solanum lycocarpum fruits glycoalkaloidic extract

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

Optimization of extraction conditions and antioxidant activity of Solanum lycocarpum fruits

Antioxidants are substances that may protect cells from the damage caused by unstable molecules known as free radicals. The capacity of natural antioxidant from phytochemical has increase attention from researchers and public. However, the extraction process is affecting the activity and the bioavailability of bioactive compounds. The Solanum lycocarpum is a plant of the Brazilian “cerrado”, popularly used as a hypoglycemic, hypocholesterolemic and control of metabolic diseases. Its effects are attributed to the presence of several glycoalkaloids (solamargine, solasonina) and solasodine. Therefore, the purpose of this communication was, investigate the optimization of extraction condition and evaluation of antioxidant activity from fruits of Solanum lycocarpum. The extracts were obtained using different solvent systems, i.e., water, 50% ethanol, ethanol absolute and ethyl ether (1:10 and 1:20) and different extraction processes: maceration with constant agitation at room temperature, maceration with constant agitation and heating at 30°C and ultrasound. The extracts were characterized by the amount of material extracted (1, 6 and 24 h) and the action of antioxidant activity by DPPH method. The results showed that the polar solvent (50% ethanol) and extractive process maceration with agitation to ambient temperature showed higher contents of extractable of fruits of S. lycocarpum (3.4 g %) and also showed higher antioxidant activity (88.57±2.41% de inhibition). This action whether the presence of glycoalkaloids (solamargine, solasonine and solasodine) in fruits S. lycocarpum which are polar compounds and may explain this increased antioxidant action of this extract.

Allelopathic potential of Equisetum giganteum L. and Nephrolepis exaltata L. on germination and growth of cucumber and lettuce

Nephrolepis exaltata L. Schott "Bostoniensis" family Davalliaceae and Equisetum giganteum L. family Equisetaceae, Phylum Pteridophyta, exhibit a strong mechanism of dominance in the areas in which they live. Have secondary compounds with allelopathic activity. The objective of this article was evaluate allelopathic potential of two ferns species, using bioassay applying aqueous extracts of dried fronds, in cucumber and lettuce seeds, and observing germination and initial development. To observe the influence on germination was analyze the percentage of germinated seeds and germination speed index (GSI). To observe initial development was analyzed shoot and root growth of the seedlings. The bioassays revealed that no concentration significantly inhibited the germination, but germination speed was delayed gradually in two species tested, as increased the extract concentration. In initial development, all the extracts showed a tendency to inhibit the growth, and an increase in extract concentration decreasing growth of radicle and hypocotyl axis. We conclude that the aqueous extract has inhibitory activity more pronounced in early development than in seed germination, affecting the primary structures of the tested plants, corroborating with the observations of occurrences of the species in natural places where dominate and suppress the growth of other species.

Osmotic potentials on water uptake and germination of Guazuma ulmifolia Lam. (Sterculiaceae) seeds

Osmotic potentials on water uptake and germination of Guazuma Ulmifolia Lam. (Sterculiaceae) seeds. This work was carried out in the Germination Lab. of the Department of Botany, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo State, Brazil. The aims of this work were to determine the water uptake curve and to evaluate the germination of Guazuma ulmifolia seeds subjected to different water potentials. For the water uptake curve, seven replicates of 50 pre-scarified seeds were placed onto paper moistened with 15 mL PEG 6000 solution under the potentials 0 (control), -0.3 and -0.6 MPa at 25o C in the darkness. For the germination assay, four replicates of 50 seeds were subjected to the same above-described conditions; however, one lot of seeds was modified when there was variation in the refractometric index, whereas the remaining ones were kept in the same solutions until the end of the experiment. All three phases of water uptake were detected under 0 and -0.3 MPa; however, phase II was prolonged under -0.6 MPa and germination was not observed. For 0 and -0.3 MPa, the adopted statistical models consisted of asymptotic (phases I and II) and exponential (phase III) functions, y = a*[1 - b*exp (-c*t) + exp (-d + e*(t - t0)]. For -0.6MPa, only the asymptotic function y = a* [1 - b* exp (-c*t)] was used since there was no evidence of germination. The germination final percentage and speed index were lower under -0.3 MPa, mainly when solutions were not replaced; besides, germination was not detected under -0.6 MPa, with or without solution replacement.

Availability of nutrients, productive properties, and quality of sunflower ( L.) seeds in acid soils amended with different molar ratios between Ca and Mg

Liming is indispensable in acid soils for amending acidity; however, the technique may alter the cation balance in soil and, consequently, may limit the availability and uptake of nutrients. We aimed to evaluate different molar ratios between calcium (Ca) and magnesium (Mg) on the availability of soil nutrients and their influence on the productive properties of sunflower and seed quality. The experiment was carried out in a greenhouse under two types of contrasting soils and six molar combinations of CaCO3and MgCO3 in amendment of soil acidity to raise base saturation to 70%. After incubation, soil analysis was undertaken to verify the ratios obtained and nutrient availability. Morphological and production variables were analyzed at the end of the experiment, as well as accumulation of nutrients in the achenes and their physiological quality. In spite of equal base saturation between the types of soil, there were differences in the available contents of these cations. The increase in the Ca contents limited the Mg contents to the critical level of the sunflower. This result had a negative influence on the production properties of sunflower and physiological quality. In contrast, there was a compensation of the crop with greater accumulation of nutrients in the achenes under lower yield.

Influence of type and amount of straw cover on weed emergence

This research was undertaken during 2003-2004 growing season to evaluate the effects of type [forage sorghum hybrid Cober Exp (Sorghum bicolor x Sorghum sudanense), forage millet (Pennisetum americanum var. BN2), finger millet (Eleusine coracana), and St Lucia grass (Brachiaria brizantha)] and amount of straw cover (5.5 and 3.0 t ha(-1)) upon the emergence of Bidens pilosa, Chamaesyce spp., Amaranthus spp., and Commelina benghalensis, under field conditions of the Brazilian Cerrado, in the region of Uberlandia-MG. The control consisted additional treatment lacking the straw cover. Emergence of weed depended on the type and amount of straw cover, as well as the weed species. The lowest number of B. pilosa seedlings was found in the presence of forage sorghum straw; Chamaesyce spp. in the lack of straw; Amaranthus spp. in the presence of higher amount of forage sorghum and forage millet, and lower amounts of forage millet and Finger Millet. All the types and amounts of straw reduced the emergency of C. benghalensis, except at the lowest level of St Lucia grass and the lack of straw.

Seed anatomy and germination of Phoenix roebelenii O'Brien (Arecaceae)

O objetivo desse trabalho foi estudar a morfologia, anatomia e o processo germinativo de sementes de Phoenix roebelenii. Para o levantamento dos dados biométricos foram utilizadas 100 sementes de frutos recém-colhidos, deixados secar ao ar por um dia. Para a germinação, quatro repetições de 50 sementes tratadas com Vitavax-Thiran foram semeadas em bandejas de plástico, contendo Sphagnum sp. como substrato e mantidas sob condições ambientais de laboratório. Detalhes da morfologia da semente foram documentados com o uso de microscopia eletrônica de varredura e esquematizados com auxílio de câmara clara, acoplada ao estereomicroscópio. Foram confeccionadas lâminas permanentes com cortes do embrião, para o estudo de sua anatomia. As dimensões médias das sementes foram: 10,32mm comprimento, 5,21mm largura e 3,91mm espessura. O peso de 1000 sementes foi de 151,1g e 1kg continha 6600 unidades. O início da germinação variou entre 27 e 58 dias. As sementes são albuminosas, com endosperma duro e o embrião é pouco diferenciado, lateral e periférico. A germinação inicia-se pela abertura de um opérculo, através do qual é emitido o pecíolo cotiledonar com o eixo embrionário na extremidade. O pecíolo funciona, internamente, como um haustório, digerindo gradativamente o endosperma. Na sua parte posterior, desenvolve-se a plúmula, que emerge através de uma fenda. Nota-se o aparecimento de raízes secundárias na porção anterior da raiz primária.

Fresh and matured lamb meat quality fed with sunflower seeds and vitamin E

O objetivo deste estudo foi avaliar a qualidade da carne de cordeiros Ile de France alimentados com dietas contendo grãos de girassol e vitamina E. Trinta e dois cordeiros pesando inicialmente 15kg foram alojados em baias individuais e abatidos ao atingir 32kg de peso corporal. Os tratamentos consistiram de quatro dietas experimentais: D1) cana-de-açúcar + concentrado sem grãos de girassol; D2) cana-de-açúcar + concentrado com grãos de girassol; D3) cana-de-açúcar + concentrado grãos de girassol, mais 1000mg de vitamina E kg-1 de matéria seca (MS) da dieta; e D4) cana-de-açúcar + concentrado com grãos de girassol e 1000mg de vitamina E dieta kg-1 de MS. Os parâmetros temperatura, pH, cor, perda de peso ao cozimento, força de cisalhamento e capacidade de retenção de água foram determinados nos tempos de maturação de 0, 7 e 14 dias no músculo Longissimus dorsi. As características qualitativas da carne não foram afetadas pelas dietas contendo grãos de girassol combinado com vitamina E, no entanto, pH 24 horas foi afetado (P<0,05) pela dieta contendo grãos de girassol com vitamina E. A perda de peso por cozimento não foi influenciada (P>0,05) pelos tempos de dieta ou de maturação, por outro lado, a força de cisalhamento e capacidade de retenção de água foi significativamente afetada (P<0,05). O uso da vitamina E resultou em carne com maior capacidade de retenção de água. O tempo de maturação influenciou nos parâmetros pH, cor e força de cisalhamento. Carne de cordeiro com 7 dias de maturação apresentou menor força de cisalhamento.

Mechanism and control of Genipa americana seed germination

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sewage sludge levels on the development and nutrition of sunflower plants

This study aimed to evaluate the effect of substituting chemical nitrogen (N) fertilization for equivalent N levels from sewage sludge of Wastewater Treatment Plant (WTP) on sunflower plant development. Nutrient levels in physiologically mature leaves and seeds, besides nutrient exportation during a 130-day assay, were also assessed. The experiment was carried out in 100 m(2) permanent plots at Sao Manuel Farm, which belongs to School of Agronomical Sciences, São Paulo State University-UNESP, Botncatu, São Paulo State, Brazil. The farm is located in the municipality of Sao Manuel, São Paulo State. Experimental design was in randomized blocks including 5 treatments and 5 replicates. Treatments were: T1 - chemical N fertilization according to the recommendation for the culture; T2 - 50% N from sewage sludge and 50% N from chemical fertilization; T3 - 100% N from sewage sludge; T4 - 150% N from sewage sludge; T5 - 200% N from sewage sludge. For all treatments, equal amounts of P and K fertilization were applied. Treatments differed for plant height from 21 to 64 days, stern diameter from 28 to 57 days, and leaf number from 21 to 38 days. Seed nutrient levels slightly varied; however, the quantities of exported N, P, Mg, Fe and Zn varied as sewage sludge levels increased.

Allelopathy and phytotoxicity of Zanthoxylum rhoifolium Lam.

In Cerrado, Zanthoxylum rhoifolium Lam. stands out because it interferes with the growth and development of other plants. The preliminary phytochemical analyses showed the presence of polyphenols and flavonoids. The Z. rhoifolium extract inhibited the germination index (5 mg mL(-1)=0.5%; 10mg mL(-1)=37.(5%) and 20mg mL(-1)=85.5%) decreased the germination and the lettuce seedlings growth (roots and the hypocotyls) and reduced the mitotic index than control. The extract of 1000 mu g mL(-1)conc contained (165.20 mg and 45.74 mg, phenols and total flavonoids, respectively) and had higher antioxidant activity (80.52%). We concluded that Z. rhofolium possesses allelopathic potential.

Mutagenicity and antimutagenicity of (-)-hinokinin a trypanosomicidal compound measured by Salmonella microsome and comet assays

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

Imbibition of Swietenia macrophylla (Meliaceae) seeds: the role of stomata

Background and Aims the occurrence of stomata in seed coats is uncommon and there is limited information about their function(s). The aim of this study was to verify the distribution of stomata in seed coats of Swietenia macrophylla and to relate it to the imbibition process and aspects of the structure of the outer integument layers.Methods For the structural and ultrastructural studies, the seeds were processed using the usual techniques and studied under light and scanning electron microscopes. Histochemical tests were employed to identify the cell wall composition in the different seed coat portions. To assess the role of the stomata in the imbibition, non-impervious seeds were compared with partially impervious ones, in which only the embryo, median or hilar regions were left free. Further, the apoplastic pathway marker was employed to confirm the role of the stomata as sites of water passage during imbibition.Key Results A positive relationship was observed between seed coat thickness and stomata density. The stomata were devoid of movement, with a large pore. They occurred in large numbers in the embryo region and extended with lower frequency towards the wing. Imbibition rates were related to stomata density, suggesting that the stomata act as preferential sites for water entry in the S. macrophylla seeds.Conclusions At maturity, the stomata in the seed coat play a significant role in seed imbibition. The data may also infer that these permanently opened stomata have an important role in gas exchange during seed development, aiding embryo respiration.