Letícia Winke Dias

Seedling length in wheat determined by image processing using mathematical tools

Seed vigour is determined by a series of laboratory tests, many of these laborious and time-consuming. In view of this, the present study aimed to compare the determination of seedling length in wheat using image processing, with the traditional method, as well as the ability of the method to determine seed vigour. The experimental design was completely randomised, with five replications comprising a single-factor experimental scheme. The data were analysed for normality by the Shapiro-Wilk test and variance analysis using ANOVA at 5% probability. The response variables were correlated using Pearsons test, and the methodologies for determining the length of the shoots and roots, by measuring with a graduated rule and by image processing, were compared using the F-test at 5% probability. To compare mean values between cultivars, Tukeys test at 5% probability was used. The length of the shoots and roots of wheat seedlings, determined by image processing using the Matlab ® mathematical tool, is efficient in separating the cultivars

Accelerated aging test in amaranth (Amaranthus cruentus L.) seeds.

The use of vigor tests for assessing seed lot quality is an important tool for production and commercialization. However, research on evaluating the quality of amaranth seeds is still scarce. The objective of this work was to evaluate procedures for conducting the accelerated aging test, aiming at the identification of different levels of vigour among lots of amaranth (Amaranthus cruentus L.) seeds cultivar BRS Alegria. Five seed lots were used and submitted to tests of germination, first count of germination, seedling emergence and accelerated aging, using the aging periods of 24, 48 and 72 hours and adopting the traditional methodology with water and the use of saturated (40g NaCl in 100mL of water) and unsaturated (11g NaCl in 100mL of water) sodium chloride (NaCl) solution. The accelerated aging test at 41oC and periods of 24, 48 and 72 hours of conditioning saturated NaCl solution allowed the stratification of the lots at vigour levels, similar to the results obtained by the seedling emergence test and the first count of germination. The accelerated aging test, using saturated saline solution (40g NaCl in 100mL of water) for 24 hours at 41°C, is therefore suitable for evaluating the physiological potential of amaranth seeds.

TRATAMENTO DE SEMENTES DE SOJA COM ZINCO: EFEITO NA QUALIDADE FISIOLÓGICA E PRODUTIVIDADE

Objetivou-se avaliar o efeito do tratamento de sementes de soja com zinco na qualidade fisiologica das sementes tratadas e produzidas bem como nas caracteristicas agronomicas. O delineamento experimental adotado foi inteiramente casualizado, em esquema fatorial 2 X 5 (Lotes: A e B; e doses da fonte: 0, 2, 4, 6 e 8 mL kg-1 de semente). Apos o tratamento das sementes, foi analisada a qualidade fisiologica das mesmas, avaliadas pelo teste de germinacao, primeira contagem de germinacao, teste frio, envelhecimento acelerado, comprimento da parte aerea e de raiz. Na sequencia foi realizada a semeadura das sementes tratadas em vasos, conduzindo o experimento ate a fase de maturacao de campo. Apos a colheita, foram avaliados as caracteristicas agronomicas e a qualidade fisiologica das sementes produzidas. As caracteristicas agronomicas foram avaliadas atraves do numero de sementes por planta, numero de legumes por planta, peso de sementes por planta. A qualidade das sementes produzidas foi avaliada pelos testes acima citados mais o teste de emergencia a campo. O tratamento das sementes de soja nas doses entre 2 a 6 mL kg de sementes-1 apresentou os melhores resultados para a qualidade fisiologica e caracteristicas agronomicas. O numero de sementes por planta, numero de legumes por planta e peso de sementes por planta apresentam incrementos com o aumento das doses de zinco. O tratamento das sementes de soja com zinco nao influencia a qualidade fisiologica das sementes produzidas. Os lotes apresentam comportamentos diferentes em resposta ao tratamento das sementes com zinco.