Resumo:A avaliação da velocidade e intensidade de germinação de lotes de sementes têm providenciado oportunidades sem precedentes para a comunidade científica. Pesquisadores requerem tais informações para rapidamente determinar a velocidade de emergência da plântula. Entretanto, uma quantidade extensa de dados é analisada para se alcançar este propósito. Neste artigo, introduzimos um software desenhado para facilitar o entendimento dos processos de germinação e a análise dos dados. O GerminaQuant 1.0 foi escrito em linguagem de programação C++ e apresenta uma interface amigável. A precisão do software foi testada a partir de cinquenta diferentes matrizes, cujos valores de saída foram comparados com outras planilhas de cálculo disponíveis na web. Com a análise dos dados foi mostrado que o GerminaQuant é capaz de gerar cálculos matemáticos com extrema precisão, além de apresentar uma performance amigável, com ampla facilidade de uso em qualquer computador. Ademais, o novo software foi testado para oitenta usuários, os quais compararam a sua funcionalidade design e precisão. Em todas as variáveis, o GerminaQuant foi avaliado como sendo superior quando comparado às demais planilhas disponíveis na web. O GerminaQuant (disponível para Windows(r), Macintosh(r) e Linux(r)) está disponível gratuitamente para download por toda a comunidade científica, através do endereço http://www.ufpe.br/lev.

Abstract:The seed technologies related with germination and seed research has provided unprecedented opportunities for the biologic research community. Researchers require such information to rapidly determine the speed of seedling emergence. However, an immense amount of data must be analyzed to achieve this goal. In this paper, we introduce a computer software designed for broad use to facilitate the understanding of germination processes and their analysis. GerminaQuant 1.0 was written in the C++ programming language and presents a user-friendly interface. The accuracy of the software was tested using fifty different matrices, whose output values were compared with other spreadsheets available on the web. With data analysis, we showed that the GerminaQuant is capable of generating mathematical calculations with extreme accuracy, besides have a good performance and wide ease of use in any kind of computer. In addition, the new software has been tested by at least eighty users, which compared functionality, designer and accuracy of the output data. In all variables, the GerminaQuant was evaluated as superior compared to other spreadsheets available on the web. The full GerminaQuant package (for Windows(r), Macintosh(r) and Linux(r)) is freely available to the scientific community and can be easily downloaded from the website (http://www.ufpe.br/lev).

Biodiesel is an alternative to petroleum diesel fuel. It is a renewable, biodegradable, and nontoxic biofuel. Interest in the production of biodiesel from Jatropha curcas L. seeds has increased in recent years, but the ability of J. curcas to grow in salt-prone areas, such as the Caatinga semiarid region, has received considerably meager attention. The aim of this study was to identify the main physiological processes that can elucidate the pattern of responses of J. curcas irrigated with saline water, which commonly occurs in the semiarid Caatinga region. This study measured the activity of the antioxidant enzymes involved in the scavenging of reactive oxygen species, which include catalase (CAT) and ascorbate peroxidase (APX), as well as malondialdehyde (MDA) levels. The levels of chlorophyll (Chl), carotenoids, amino acids, proline, and soluble proteins were also analyzed. The net carbon assimilation rate (P N), stomata conductance (g s), and transpiration rate (E) decreased with salt stress. The activities of CAT and APX were decreased, while H2O2 and MDA levels as well as electrolyte leakage were significantly increased in salt-stressed plants compared to the untreated ones. These observations suggest that the ability of J. curcas plants resist to salt stress is associated with the activities of protective enzymes and their defensive functions. However, our results indicate that the reactive oxygen species scavenging system is not sufficient to protect J. curcas leaves against oxidative damage caused by salt stress, and, therefore, it cannot be treated as a salt tolerant plant species.