Bromofhenol blue discoloration using peroxidase immobilized on highly activated corncob powder

The aim of the present study was to evaluate the efficacy of peroxidase immobilized on corncob powder for the discoloration of dye. Peroxidase was extracted from soybean seed coat, followed by amination of the surface of the tertiary structure. The aminated peroxidase was immobilized on highly activated corncob powder and employed for the discoloration of bromophenol blue. Amination was performed with 10 or 50 mmol.L-1 carbodiimide and 1 mol.L-1 ethylenediamine. The amount of protein in the extract was 0.235 ± 0.011 mg.mL-1 and specific peroxidase activity was 86.06 ± 1.52 µmol min-1 . mg-1, using 1 mmol.L-1 ABTS as substrate. Ten mmol.L-1 and 50 mmol.L-1 aminated peroxidase retained 88 and 100% of the initial activity. Following covalent immobilization on a corncob powder-glyoxyl support, 10 and 50 mmol.L-1 aminated peroxidase retained 74 and 86% of activity, respectively. Derivatives were used for the discoloration of 0.02 mmol.L-1 bromophenol blue solution. After 30 min, 93 and 89% discoloration was achieved with the 10 mmol.L-1 and 50 mmol.L-1 derivatives, respectively. Moreover, these derivatives retained 60% of the catalytic properties when used three times. Peroxidase extracted from soybean seed coat immobilized on a low-cost corncob powder support exhibited improved thermal stability.

Estudo genético de populações de soja com fonte de resistência à Heterodera glycines (raça 3) oriundas de topocruzamentos tipo alimento x tipo grão

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade de sementes de soja colhidas de forma manual e mecânica com diferentes teores de água

A colheita é uma das principais etapas no processo de produção de sementes de soja. O momento adequado para se efetuar a colheita pode variar em função do tipo de colheita e do grau de umidade das sementes. Neste sentido, o objetivo dessa pesquisa foi determinar as alterações fisiológicas de sementes de soja colhidas de forma manual e mecânica com diferentes teores de água. Para tanto, utilizaram-se sementes das cultivares Embrapa 48 e FTS Águia, que têm diferenças no teor de lignina do tegumento, colhidas de forma manual e mecanicamente com 18,0; 15,0 e 12,0% de água. Após a colheita, as sementes foram submetidas à secagem, e a qualidade das sementes foi avaliada pelos testes de germinação, emergência de plântulas, tetrazólio (viabilidade e vigor), envelhecimento acelerado e índice de velocidade de emergência de plântula. Em seguida, as sementes foram armazenadas (20 °C e 45% UR do ar) e analisadas logo após a colheita e aos seis meses de armazenamento. Os resultados obtidos indicam que o parâmetro fisiológico das sementes de soja, não é afetado, quando: se realiza colheita manual com grau de umidade das sementes de 11,4% a 18,4%; e para sementes colhidas à máquina, com grau de umidade entre 12,0% a 15,9%; mantendo a qualidade fisiológica mesmo após seis meses de armazenamento.

Tratamiento con ácido sulfúrico de semillas de la acacia blanca (Robinia pseudo acacia L.) cosechadas en Mendoza

The results obtained in germination test with seeds of "black locust" (Robinia Pseudo Acacia L) previously treated with sulphuric acid concentrated (d. 1.84) are given. Those test were made in order to get a good germination considering the water tight seed coat that those seeds have in a great percentage. The seeds were soaked in the solution for some minutes; the 180 and 210 minutes soaking (90 and 86.5 % respectively) gave the highest percentage and the fasted process of germination, which were higher than those obtained as efective by other researches. The test made would constitute another evidence of the effect of the locality of production upon the degree of water tightness of the Black locust seeds. The author suggests that the previous treatments of the seeds, the rusticity and quick growing of this species and the furrow system of irrigation so common in the zone will enable, perhaps with success the stablishment of woods of this valuable forestal species, by direct seeding.

20 movies of x-ray tomograms of different Alpinia fossils

The fossil floras described by Dieter MAI and Harald WALTHER are invaluable for understanding the past plant diversity in Europe, and provide important information on the occurrence of taxa in the fossil record that is critical for evolutionary studies. Among the taxa they recognized were seeds assigned to the extant genus Alpinia ROXB. (Zingiberaceae, Zingiberales). We reinvestigated 28 specimens that were assigned to Alpinia arnensis (CHANDLER) MAI, Alpinia cf. arnensis, and Alpinia bivascularis MAI from the Ypresian (lower Eocene) of the UK, upper Eocene of Germany, and lower Miocene of Germany using non-destructive synchrotron-based X-ray tomography to reveal internal anatomy. None of the samples studied show an anatomy consistent with extant Alpinia or even Zingiberales. The fossils lack the globose shape, often striate external surface, seed coat structure, operculum, and micropylar collar seen in all Alpinia, and lack the chalazal chamber seen in many Alpinia species. Two specimens from the lower Miocene of Germany showed the structure of fruits of Caricoidea CHANDLER (Cyperaceae) with a single-layered exocarp, thick mesocarp, and sclerified endocarp. The other specimens are recognized as Carpolithes albolutum nom. nov. (incertae sedis) from the Ypresian of the UK, C. phoenixnordensis sp. nov. (incertae sedis) from the upper Eocene of Germany, C. bivascularis comb. nov. (incertae sedis) from the lower Miocene of Germany as well as indeterminate tegmens from the lower Miocene of Germany. This reinvestigation demonstrates that there is, as yet, no confirmed fossil record for the extant genus Alpinia. Furthermore, at least four different taxa are recognized from what had been two extinct species, enhancing our understanding of these important European Cenozoic carpofloras.

Arginase Is Inoperative in Developing Soybean Embryos1

Arginase (EC 3.5.3.1) transcript level and activity were measured in soybean (Glycine max L.) embryos from the reserve deposition stage to postgermination. Using a cDNA probe for a small soybean arginase gene family, no transcript was detected in developing embryos. However, arginase transcripts increased sharply on germination, reaching a maximum at 3 to 5 d after germination. There was low but measurable in vitro arginase specific activity in developing embryos (less than 6% of seedling maximum). During germination arginase specific activity increased in parallel with the sharply increasing arginase transcript level. Seedling arginase activity was largely localized in cotyledons. Arginase activity was assayed in vivo by measuring urea accumulation in a urease-deficient mutant. No urea was detected in developing embryos, whereas accumulated urea paralleled arginase specific activity and transcript level in germinating seedlings. As in planta embryos, cultured cotyledons did not accumulate urea when arginine (Arg) was provided with other amino acids in a “mock” seed-coat exudate. Arg as the sole nitrogen source was converted to urea but did not support cotyledon growth. There appeared to be a lack of recruitment of the low-level arginase activity to hydrolyze free Arg in developing embryos, thus avoiding a futile urea cycle.

A mutation that allows endosperm development without fertilization.

The mechanisms that initiate reproductive development after fertilization are not understood. Reproduction in higher plants is unique because it is initiated by two fertilization events in the haploid female gametophyte. One sperm nucleus fertilizes the egg to form the embryo. A second sperm nucleus fertilizes the central cell to form the endosperm, a unique tissue that supports the growth of the embryo. Fertilization also activates maternal tissue differentiation, the ovule integuments form the seed coat, and the ovary forms the fruit. To investigate mechanisms that initiate reproductive development, a female-gametophytic mutation termed fie (fertilization-independent endosperm) has been isolated in Arabidopsis. The fie mutation specifically affects the central cell, allowing for replication of the central cell nucleus and endosperm development without fertilization. The fie mutation does not appear to affect the egg cell, suggesting that the processes that control the initiation of embryogenesis and endosperm development are different. FIE/fie seed coat and fruit undergo fertilization-independent differentiation, which shows that the fie female gametophyte is the source of signals that activates sporophytic fruit and seed coat development. The mutant fie allele is not transmitted by the female gametophyte. Inheritance of the mutant fie allele by the female gametophyte results in embryo abortion, even when the pollen bears the wild-type FIE allele. Thus, FIE carries out a novel, essential function for female reproductive development.

Improved germination of the Australian natives: Hibbertia commutata, Hibbertia amplexicaulis (Dilleniaceae), Chameascilla corymbosa (Liliaceae) and Leucopogon nutans (Epacridaceae)

Hibbertia commutata (Steudel), H. amplexicaulis (Steudel), Chameascilla corymbosa [(R.Br.) F.Muell. Ex Benth.] and Leucopogon nutans (E. Pritzel) are four Australian species that are difficult to germinate during mine-site rehabilitation. Laboratory germination trails were conducted to identify dormancy mechanisms and to improve germination response. Treatments applied to all species included scarification and scarification followed by soaking seeds in smoke water (1, 5 or 10%) or gibberellic-acid solution (50, 200 or 1000 muM). Additional treatments with kinetin solution (50, 200 or 1000 muM) and smoke water (50 or 100%) were applied to scarified or unscarified seeds of C. corymbosa. Thermal-shock treatment was applied to L. nutans fruit, some of which were subsequently scarified and subjected to both smoke water (10%) and gibberellic-acid solution (1000 muM). Significant germination increases were obtained by using dormancy-breaking treatments on H. commutata ( from 12.8 to 76.0%), H. amplexicaulis (from 6.8 to 55.1%) and C. corymbosa (from 48.5 to 86.4%). Scarification alone increased germination of both Hibbertia species, suggesting that these species display a physical seed coat-imposed dormancy mechanism. Germination of H. amplexicaulis was further increased by the application of gibberellic-acid solution, indicating a possible embryo-imposed dormancy mechanism. Scarification followed by the application of smoke water produced the highest germination response for C. corymbosa seeds. Scarification alone did not significantly increase germination, inferring the existence of a smoke-responsive embryo dormancy mechanism. Seeds of L. nutans, although viable, failed to germinate and are thought to display complex seed coat- and embryo-imposed dormancy mechanisms.

The effects of temperature and salinity on Acacia harpophylla (brigalow) (Mimosaceae) germination

Acacia harpophylla F. Muell. (brigalow) used to naturally occur over a range of about 50 000 km(2) in Queensland and New South Wales, Australia. Large scale clearing for agriculture has reduced the area to less than 20 000 km(2) and it is estimated that 20-25% of vertebrate fauna living in brigalow communities will become locally extinct as a result of the current clearing induced loss of habitat. Some coal mining companies in central Queensland have become interested in providing habitat for the endangered bridle nail-tailed wallaby that lives in brigalow vegetation. However, there is little known about establishment techniques for brigalow on mine sites and other disturbed ground; an understanding of brigalow biology and ecology is required to assist in the conservation of this threatened vegetation community and for re-creation of bridled nail-tail wallaby habitat in the post mining landscape. Brigalow is an unusual species of Acacia because it is not hard-seeded and germinates readily without the need to break seed-coat imposed dormancy. Germination trials were undertaken to test the ability of brigalow seed to germinate with a range of temperatures and salinity levels similar to those experienced in coal mine spoil. Optimum germination was found to occur at temperatures from 15 to 38 degrees C and no germination was recorded at 45 degrees C. Brigalow was very tolerant of high salt levels and germinated at percentages greater than 50% up to the highest salinity tested, 30 dS/m. Germination of greater than 90% occurred up to an electrical conductivity of 20 dS/m. The results indicate brigalow seed can be sown in summer when rains are most likely to occur, however, shading of the seed with extra soil or mulch may ensure the ground surface does not become too hot for germination. Because of its ability to germinate at high salinity levels, brigalow may be suitable for use in saline mine wastes which are common on sites to be rehabilitated after mining.

Qualidade fisiológica de sementes de Moringa oleifera lam. por meio da análise de imagens

Several tests that evaluate the quality of seeds are destructive and require time, which is considered long and expensive in the processes that involves the production and marketing of seed. Thus, techniques that allow reducing the time related to assess the quality of seed lots is very favorable, considering the technical, economic and scientific point of view. The techniques images of seed analyzed both by X-ray such as digital images, represent alternative for this sector, and are considered reproducible and fast, giving greater flexibility and autonomy to the activities of production systems. Summarily, the objective was to analyze the internal morphology of seeds of this species through x-rayed images and the efficiency of weed seed area increased during soaking through image analysis and compare them with the results of germination tests and force the evaluation of physiological seed quality. For X-ray tests, the seeds were exposed for 0.14 seconds at radiation 40kV and 2.0 mAs. Were analyzed images using the ImageJ program and subsequently put to germinate in B.O.D chamber at 27 ° C, in which there was the comparison of results for germination. To determine the test area increase (% IA), seeds were used with and without seed coat, maintained the B.O.D chamber at 15 ° to 20 ° C, the seeds were photographed before and after the soaking period, the results were compared to the germination rates. For the X-ray test, it was observed that seeds with empty area greater than 20%, showed a higher percentage of abnormal seedlings. And the area increment analysis showed that it is possible to rank the batch after 8 hours of imbibition at 15 ° C according to the germination and vigor tests

Nutrient content in aboveground biomass of Brazilian peanut cultivars in conservation tillage on sugarcane straw and pasture area.

Fields studies were conducted in 2004/2005 in order to evaluate the effects of tillage on nutrient content in aboveground biomass of two peanut cultivars, cultivated in rotation after mechanical harvested sugarcane and pastures. These trials were carried out in two types of soils; Oxisol and Ultisol, respectively in Ribeir?ao Preto and Mirassol, S?ao Paulo State, Brazil. The experimental design was split-plot with four replications. Tillage treatments (conventional, minimum and no-tillage) were main plots while sub-plots were peanut genotypes IAC-Tatu ST (Valencia market-type, erect growth habit, red seed coat, maturity range around 100 days after planting) and IAC-Caiap´o (Runner market-type, prostate growth habit, pink testa, maturity range more than 135 days). From 15 to 90 days after emergence, samples of leaves and stems were harvested, dried, weighted and ground to determine macro and micronutrient concentration. At 75 days after sowing, the cultivar IAC-Caiap´o showed higher contents of N, P, K, Cu, and Zn while IAC-Tatu presented higher concentrations of Ca, Mg, and S. Zn content was higher in conservation tillage than in conventional, mainly in Oxisoil for both of cultivars.

Seed biometry and the effect of pre germinative treatments, temperature, and light on seed germination and subsequent growth of three Stryphnodendron species

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Error, Bias, and Long-Branch Attraction in Data for Two Chloroplast Photosystem Genes in Seed Plants

Sequences of two chloroplast photosystem genes, psaA and psbB, together comprising about 3,500 bp, were obtained for all five major groups of extant seed plants and several outgroups among other vascular plants. Strongly supported, but significantly conflicting, phylogenetic signals were obtained in parsimony analyses from partitions of the data into first and second codon positions versus third positions. In the former, both genes agreed on a monophyletic gymnosperms, with Gnetales closely related to certain conifers. In the latter, Gnetales are inferred to be the sister group of all other seed plants, with gymnosperms paraphyletic. None of the data supported the modern ‘‘anthophyte hypothesis,’’ which places Gnetales as the sister group of flowering plants. A series of simulation studies were undertaken to examine the error rate for parsimony inference. Three kinds of errors were examined: random error, systematic bias (both properties of finite data sets), and statistical inconsistency owing to long-branch attraction (an asymptotic property). Parsimony reconstructions were extremely biased for third-position data for psbB. Regardless of the true underlying tree, a tree in which Gnetales are sister to all other seed plants was likely to be reconstructed for these data. None of the combinations of genes or partitions permits the anthophyte tree to be reconstructed with high probability. Simulations of progressively larger data sets indicate the existence of long-branch attraction (statistical inconsistency) for third-position psbB data if either the anthophyte tree or the gymnosperm tree is correct. This is also true for the anthophyte tree using either psaA third positions or psbB first and second positions. A factor contributing to bias and inconsistency is extremely short branches at the base of the seed plant radiation, coupled with extremely high rates in Gnetales and nonseed plant outgroups. M. J. Sanderson,* M. F. Wojciechowski,*† J.-M. Hu,* T. Sher Khan,* and S. G. Brady

Utilisation of seed resources by small mammals : a two-way interaction

Within the Australian wet tropics bioregion, only 900 000 hectares of once continuous rainforest habitat between Townsville and Cooktown now remains. While on the Atherton Tableland, only 4% of the rainforest that once occurred there remains today with remnant vegetation now forming a matrix of rainforest dispersed within agricultural land (sugarcane, banana, orchard crops, townships and pastoral land). Some biologists have suggested that remnants often support both faunal and floral communities that differ significantly from remaining continuous forest. Australian tropical forests possess a relatively high diversity of native small mammal species particularly rodents, which unlike larger mammalian and avian frugivores elsewhere, have been shown to be resilient to the effects of fragmentation, patch isolation and reduction in patch size. While small mammals often become the dominant mammalian frugivores, in terms of their relative abundance, the relationship that exists between habitat diversity and structure, and the impacts of small mammal foraging within fragmented habitat patches in Australia, is still poorly understood. The relationship between foraging behaviour and demography of two small mammal species, Rattus fuscipes and Melomys cervinipes, and food resources in fragmented rainforest sites, were investigated in the current study. Population densities of both species were strongly related with overall density of seed resources in all rainforest fragments. The distribution of both mammal species however, was found to be independent of the distribution of seed resources. Seed utilisation trials indicated that M.cervinipes and R.fuscipes had less impact on seed resources (extent of seed harvesting) than did other rainforest frugivores. Experimental feeding trials demonstrated that in 85% of fruit species tested, rodent feeding increased seed germination by a factor of 3.5 suggesting that in Australian tropical rainforest remnants, small mammals may play a significant role in enhancing germination of large seeded fruits. This study has emphasised the role of small mammals in tropical rainforest systems in north eastern Australia, in particular, the role that they play within isolated forest fragments where larger frugivorous species may be absent.