Tereza Cristina de Carvalho

Tetrazolium test adjustment for wheat seeds

The assessment of the germination test in wheat seeds varies from 4 to 15 days, because the species normally presents dormancy in freshly harvested seeds. The tetrazolium test can characterize seed viability in less than 24 hours including lots with dormancy seeds. The objective of this study was to develop a practical and efficient procedure for evaluating the viability of wheat seeds using the tetrazolium test. Five seed lots of the BRS 208 cultivar were used, where the following were tested: a) pre-conditioning between moist paper towels or direct immersion in water for 18 hours, at 20 °C; b) longitudinal section of the embryo and the endosperm; c) coloration on paper or by immersion for 2 and 3 hours, at 30 and 40 °C; and d) concentrations of tetrazolium solution at 0.075%, 0.1%, 0.5% and 1.0%. The tetrazolium test may be efficiently used to evaluate wheat seed viability by pre-conditioning the seeds between paper towels (18 hours, at 20 °C) and adopting the following combinations of preparation and coloration: coloration of both halves of the seed on paper (2 hours, at 30 °C), in a 1.0% tetrazolium solution; or coloration of one half of the seed by immersion (3 hours, at 30 °C), in a 0.1% tetrazolium solution; or coloration of one half of the seed by immersion (2 hours, at 40 °C), in a 0.075% tetrazolium solution. This latter procedure is recommended for identifying and discarding lots with lower viability.

Electrical conductivity of different common bean seeds genotypes

The electrical conductivity test is a fast and non-subjective method used to assess seed physiological potential. Thus, the objective of this study was adapting the methodology for conducting the electrical conductivity test in common bean seeds and investigate effects of genotype in results of the test, comparing cultivars of the two trade groups: Carioca and Black. The study was conducted in two phases: 1- tests with combinations of different temperatures (20, 25, 30, and 35 °C) and five different inhibition periods (4, 8, 16, 20 and 24 h); and 2- assessment of influence of genotype by comparing results obtained on the seeds of both groups. Tests of accelerated aging and seedling emergence in field were also performed. It was concluded that, for seeds of common beans, electrical conductivity test may be performed with samples of 50 seeds per replication, soaked into 75 mL deionized water, incubated at 25 °C, and performing reading of results after 20 or 24 h. It was also concluded that test efficiency is variable according to genotype, and that for the trade group Carioca, there is not genotype effect; although the same results have not occurred for results obtained for the trade group Black.

Germinação de sementes de Physalis angulata L.: estádio de maturação do cálice e forma de armazenamento

The harvest stage of Physalis angulata L. aiming human consumption is set in literature. However, there are no criteria for harvesting fruits for seed propagation. This study aimed to determine the harvest stage of P. angulata L. seeds according to the fruit calyx color, as well as evaluating their storage viability. For that, fruits were harvested from matrix plants, considering three maturity stages, according to the calyx color (green, yellow and yellow-brownish). A completely randomized design was used, in a factorial arrangement comprising two kinds of package (paper bag and glass container) and four evaluation periods (after harvesting and at 45, 90 and 135 days after storage - DAS), being isolated the factor storage environment. It was concluded that P. angulata seeds should be collected from fruits with a green calyx and used soon after being harvested, since seed germination sharply decreases after 45 DAS, both in the storage chamber and in the refrigerated environment, regardless of whether glass or paper is used.

Comparação da qualidade fisiológica de sementes de soja convencional e de sua derivada transgênica

Os avancos na pesquisa tem resultado em varias opcoes praticas ao agricultor moderno, como o surgimento da soja transgenica. No entanto, vem sendo levantada a hipotese de que sementes de soja convencional, e sua versao transgenica RR, apresentam diferencas quanto a qualidade fisiologica. Dessa maneira, objetivou-se comparar a qualidade fisiologica de sementes de soja convencional e sua derivada transgenica RR, por meio de varios testes empregados na analise de sementes. Para isso, foram utilizados oito lotes de sementes de soja, sendo quatro lotes da cultivar CD 206 e quatro da cultivar CD 206 RR, produzidas no Estado do Parana. As sementes foram avaliadas quanto ao grau de umidade, curva de embebicao e comportamento nos testes de germinacao, emergencia de plântulas em casa de vegetacao, tetrazolio (viabilidade e vigor), envelhecimento acelerado e pelos indices de velocidade de germinacao e velocidade de emergencia. Com base nos resultados obtidos, concluiu-se que as sementes de soja convencional apresentaram potencial fisiologico superior em relacao as da derivada transgenica.

Methods for assessment of pre-harvest sprouting in wheat cultivars

The objective of this work was to test methods for pre-harvest sprouting assessment in wheat cultivars. Fourteen wheat cultivars were grown in Londrina and Ponta Grossa municipalities, Parana state, Brazil. They were sampled at 10 and 17 days after physiological maturity and evaluated using the methods of germination by rainfall simulation (in a greenhouse), in-ear grain sprouting, and grains removed from the ears. The in-ear grain sprouting method allowed the differentiation of cultivars, but showed different resistance levels from the available description of cultivars. The sprouting of grain removed from the ears did not allow a reliable distinction of data on germination in any harvest date or location. The method of rainfall simulation is the most suitable for the assessment of cultivars as to pre-harvest sprouting, regardless of the sampling date and evaluated location.

Efeito de fungicidas para controle da ferrugem asiática na qualidade de sementes de soja

The residual effect was assessed of fungicides to control Asian rust (Phakopsora pachyrhizi) in soybean seeds of the BRS-133 cultivar using 13 treatments (without fungicide, Priori + Nimbus, Aproach + Nimbus, Priori Xtra + Nimbus, Sphere + Aureo, Opera, Stratego + Aureo, Nativo + Aureo, Impact Duo + Oppa, Celeiro + Iharol, Battle + Oppa, Aproach Prima + Nimbus, Folicur ). The residual effect of the fungicides was analyzed by the germination test, accelerated aging, germination in sand and the seed health test. The treatments did not change the quality of the seeds and the treatment Battle + Oppa was efficient to control the pathogen Cercospora kikuchii on the seeds.

Germinação e desenvolvimento inicial de plântulas de soja convencional e sua derivada transgênica RR em condições de estresse salino

Brazil stands out as the largest worldwide producer of transgenic soybeans and has extended its production mainly to regions with saline soils, where there is accumulation of salts that interferes in seed germination and seedling development. The object of this research was to evaluate the effect of saline stress on the germination and initial development of soybean conventional seedling and its transgenic derivatives Roundup Ready (RR) submitted to different salinity conditions. For that purpose two lots of soybean seeds were used (CD 206 and CD 206 RR), the treatments consisted of the following levels of NaCl: 0, 5, 15, 30, 60 and 120mmol L-1. The evaluation of physiological seed quality was obtained by germination test, root and seedling length, seedling dry mass and volume of roots. The salt stress reduced germination of seeds of both genotypes, and the development of seedling of genotype transgenic RR is less sensitive in conditions of greater salinity (60 to 120mmol L-1 of NaCl).

Cloud Distributed Processing Using Trade Wind

This paper presents the distributed processing feature for Trade Wind, a cloud deployment and management solution. The main objective of this research is to evaluate performance and feasibility of this feature for big data applications. A prototype has been created and tested in the calculation of monthly average temperature and humidity based on data from a public data set. Preliminary results show great improvement in terms of time reduction, speedup, and efficiency.

Distributed Processing from Large Scale Sensor Network Using Hadoop

Big data refers to large amounts of data, normally in unstructured forms, such as text, sensor data, audio, video, log files, and more. When collecting from a large number of nodes, sensor networks can produce large data sets. Climate and sensor network data are applied to assist the decision making process in agricultural production. In this paper we present the main aspects of a prototype to test Hadoop framework applied to process climate related data sets in a cloud computing infrastructure.

Teste de condutividade elétrica para avaliação do potencial fisiológico de sementes de aveia preta

Electrical conductivity test for assessing the physiological potential of black oat seeds Companies have been increasingly seeking to improve the internal control of seeds quality and, faster methods to assess seeds vigor, such as electrical conductivity test, is a useful tool in decision making about the final destination of the lots. Thus, the objective of the present study was to evaluate the electrical conductivity test to estimate the vigor of black oat seeds, in order to establish an ef ficient methodology for implementation. Were used four lots of black oats cultivar ‘IAPAR 61 (Ibipora)’, being assessed: a) number of seeds: 50 to 100 seeds in shell, b) soaking volumes: 50, 75 and 100 mL of deionized water, c) soaking periods: 4, 8, 16 and 20 hours, under constant germinator temperature at 20 °C. At the same time, moisture content of seeds and the conduct of germination and seedling emer gence were evaluated in the field. Data were analyzed in completely randomized design, with four replicates. The electrical conductivity test for black oat seeds can be achieved by using 100 seeds in shell, soaked in 100 mL of deionized water, at 20 °C, for 16 or 20 hours.