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Bento Gonçalves, Brazil

This study aimed to estimate the coefficients of repeatability (r), determination or degree of predictability (R2) of clones characteristics of wine grapes varities, and determine the number of measurements required, capable to provide levels of certainty (80, 90 and 95%) of the real prediction l value of individuals for each character. The study was conducted from average data of eight characteristics from two experiments on the behavior of clones from two grape varieties, evaluated between the years 1989 and 1992. Based on the average of two experiments of each harvest, it was obtained estimates of the repeatability coefficient () and the coefficient of determination or degree of predictability (R2) for all traits. In the estimation of the repeatability coefficient, the method of analysis of variance was used. Coefficient of repeatability obtained for the two varieties have values very similar magnitude. Repeatability estimates for the eight characteristics are superior to 0.60, demonstrating constancy of clones performance in several crops and reliable genotypic discrimination more than 80%. The use of three crops is suitable for the selection to be accomplished with predictability of the real value of above 80% genotype. © 2015, Universidade Federal de Santa Maria. All Rights Reserved. Source

Berenschot A.S.,Instituto Agronomico | Quecini V.,Embrapa Uva e Vinho
Physiology and Molecular Biology of Plants | Year: 2014

Flower color and plant architecture are important commercially valuable features for ornamental petunias (Petunia x hybrida Vilm.). Photoperception and light signaling are the major environmental factors controlling anthocyanin and chlorophyll biosynthesis and shade-avoidance responses in higher plants. The genetic regulators of these processes were investigated in petunia by in silico analyses and the sequence information was used to devise a reverse genetics approach to probe mutant populations. Petunia orthologs of photoreceptor, light-signaling components and anthocyanin metabolism genes were identified and investigated for functional conservation by phylogenetic and protein motif analyses. The expression profiles of photoreceptor gene families and of transcription factors regulating anthocyanin biosynthesis were obtained by bioinformatic tools. Two mutant populations, generated by an alkalyting agent and by gamma irradiation, were screened using a phenotype-independent, sequence-based method by high-throughput PCR-based assay. The strategy allowed the identification of novel mutant alleles for anthocyanin biosynthesis (CHALCONE SYNTHASE) and regulation (PH4), and for light signaling (CONSTANS) genes. © 2013 Prof. H.S. Srivastava Foundation for Science and Society. Source

The protected cultivation of grapes is an alternative to reduce the incidence of fungal diseases in regions with excess rainfall. The use of plastic covering on vine planting rows produces changes in the microclimate around the plant, due mainly to the absence of freely available water on leaves and berries. These changes hinder the development of fungal diseases, such as bunch rot - currently one of the biggest challenges in disease control in traditional grape growing regions like Serra Gaúcha - and reduce fungicide use. However, powdery mildew, whose incidence under high relative humidity conditions is usually low, must be closely monitored in protected cultivation. Also, fungicides must be used with caution as plastic covering reduces the incidence of ultraviolet radiation and rainfall on clusters, thereby increasing the residual effect of fungicides. The higher accumulation of fungicide on grapes directly affects their in natura consumption and compromises yeast fermentation during the winemaking process. In general, plastic covering is efficient in controlling fungal diseases and in reducing fungicide use, but it must be regarded as a new cultivation system as it requires distinct disease control compared to conventional cultivation. The used plastic covering must be regarded as crop residues, demanding specific precautions against environmental contamination. Source

Sprayers handling pads, among other designations, are described as sites intended for the preparation of pesticides and load of agricultural pulverization equipments. By the environmental and labour legislation, these points are seen as environmental security equipment in the rural surroundings (environment). There is enough technical bibliography that describes the constructive and handling processes of such sites, but there is insufficient clarity about how this consensual manner was reached, with little scientific basis about its collective advantages and risks. Some aspects such as the impermeabilization, material formation, management of floor and residue of agrochemicals, interfere in the capacity of preventing possible polluters reaching the soil, surface and groundwater, also influencing its final disposal. Some functional aspects still require answers, such as possibility of the floor retaining and storing the pollutant and becoming a emitter in long-term, the definition lifetime equipment, amongst others. Recently there have been advances in the constructive philosophy of sprayers handling pads, with the introduction of residue redressing in situ, through biodegradation which became known as biobeds, amongst others. The objective of this revision is to discuss the different types of floor bads and management of these places, its risks and possibilities of becoming environmental liabilities. Source

The amount of water used in irrigation systems is usually calculated using the local reference evapotranspiration (ETo) values. Several methods can be used for ETo calculation, and Hargreaves method is one of the most popular. This method uses estimated values of global solar radiation (Rs), based on the difference between the maximum (Tmax) and minimum (Tmin) air temperature. However, the Rs may be calculated by other methods, such as the Bristow-Campbell, which also is based on the difference between Tmax and Tmin. In this study were estimated daily values of ETo by the method of Hargreaves in Jales - SP, Brazil, with and without the use of the Bristow-Campbell equation to calculate the Rs. These values were compared with those from the Penman-Monteith method, which is considered standard for the estimation of ETo. The evaluations had considered the wet and dry periods in the region. The use of the Bristow-Campbell equation improved the performance of the Hargreaves method, in relation to the Penman-Monteith, and the performance during the dry period of the year was higher than that of the wet season. Source

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