10 research outputs found

    A reference high-pressure CH<sub>4</sub> adsorption isotherm for zeolite Y: results of an interlaboratory study

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    This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess methane adsorption isotherms on NIST Reference Material RM 8850 (Zeolite Y), at 25 °C up to 7.5 MPa. Twenty laboratories participated in the study and contributed over one-hundred adsorption isotherms of methane on Zeolite Y. From these data, an empirical reference equation was determined, along with a 95% uncertainty interval (Uk=2). By requiring participants to replicate a high-pressure reference isotherm for carbon dioxide adsorption on NIST Reference Material RM 8852 (ZSM-5), this interlaboratory study also demonstrated the usefulness of reference isotherms in evaluating the performance of high-pressure adsorption experiments

    Genomics-assisted breeding in four major pulse crops of developing countries: present status and prospects

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    The global population is continuously increasing and is expected to reach nine billion by 2050. This huge population pressure will lead to severe shortage of food, natural resources and arable land. Such an alarming situation is most likely to arise in developing countries due to increase in the proportion of people suffering from protein and micronutrient malnutrition. Pulses being a primary and affordable source of proteins and minerals play a key role in alleviating the protein calorie malnutrition, micronutrient deficiencies and other undernourishment-related issues. Additionally, pulses are a vital source of livelihood generation for millions of resource-poor farmers practising agriculture in the semi-arid and sub-tropical regions. Limited success achieved through conventional breeding so far in most of the pulse crops will not be enough to feed the ever increasing population. In this context, genomics-assisted breeding (GAB) holds promise in enhancing the genetic gains. Though pulses have long been considered as orphan crops, recent advances in the area of pulse genomics are noteworthy, e.g. discovery of genome-wide genetic markers, high-throughput genotyping and sequencing platforms, high-density genetic linkage/QTL maps and, more importantly, the availability of whole-genome sequence. With genome sequence in hand, there is a great scope to apply genome-wide methods for trait mapping using association studies and to choose desirable genotypes via genomic selection. It is anticipated that GAB will speed up the progress of genetic improvement of pulses, leading to the rapid development of cultivars with higher yield, enhanced stress tolerance and wider adaptability

    Avaliação da capacidade de produzir fitotoxinas in vitro por parte de fungos com propriedades antagônicas a nematóides In vitro evaluation of the phytotoxin production ability by fungi with antagonic properties to nematodes

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    Em trabalho preliminar foram obtidos 24 isolados fúngicos com propriedades antagônicas a nematóides parasitas de plantas segundo experimentos realizados em laboratório. Para dar continuidade a tal trabalho, tornou-se desejável dispor de metodologia simples e de baixo custo para selecionar aqueles sem capacidade de produção de substâncias fitotóxicas, para serem empregados em experimentos em casa-de-vegetação com fitonematóides. Conseqüentemente, cultivaram-se os fungos em meio líquido e, após filtração, as fases líquidas foram liofilizadas e extraídas com acetato de etila/metanol. Os extratos foram concentrados sob vácuo e dissolvidos em água e solução de sacarose para serem submetidos a testes in vitro com sementes de alface (Lactuca sativa L.) e com coleóptilos de trigo (Triticum aestivum L.), respectivamente. Vinte e três isolados pertencentes aos gêneros Arthrobotrys, Aspergillus, Coniothyrium, Cunninghamella, Cylindrocarpon, Fusarium, Monacrosporium, Mortierella, Paecilomyces, Penicillium, Sclerotinia, Trichoderma e Verticillium, apresentaram atividade tóxica contra os coleóptilos de trigo. Apenas os isolados de Cylindrocarpon magnusianum (Sacc.) Wollenw., Fusarium moniliforme Shelden, Mortierella sp., Paecilomyces lilacinus (Thom.) Samson e Penicillium sp. apresentaram atividade fitotóxica no teste com sementes de alface. Somente um isolado de F. moniliforme se mostrou inativo em ambos os testes, o que sugere que não seja produtor de fitotoxinas.<br>In a previous work 24 fungi cultures were selected due to their antagonic properties to phytonematodes in laboratory experiments. To proceed to further studies, it became desirable to use a simple and inexpensive methodology to identify those fungi able to produce phytotoxic substances, so that only the non phytotoxin producers could be used in green-house experiments with plant parasite nematodes. Thus, fungi were grown in liquid medium and the resulting mixtures were submitted to filtration. The liquid phases were freeze-dried and extracted with ethyl acetate/methanol. After extracts concentration under vacuum, the remaining substances were dissolved in water and aqueous saccharose solution to be submitted to in vitro assays with lettuce seeds (Lactuca sativa L.) and wheat coleoptile (Triticum aestivum L.), respectively. Twenty three isolates from genera Arthrobotrys, Aspergillus, Coniothyrium, Cunninghamella, Cylindrocarpon, Fusarium, Monacrosporium, Mortierella, Paecilomyces, Penicillium, Sclerotinia, Trichoderma and Verticillium, presented toxic activity against wheat coleoptile, though only isolates of Cylindrocarpon magnusianum (Sacc.) Wollenw., Fusarium moniliforme Shelden, Mortierella sp., Paecilomyces lilacinus (Thom.) Samson and Penicillium sp., presented phytotoxic effects in the lettuce seeds assay. Only one isolate of F. moniliforme was inactive in both assays, what suggests that this fungus is not able to produce phytotoxins
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