Qualidade fisiológica de sementes de trigo em resposta aos efeitos de anos e épocas de semeadura

the objective of this study was to evaluate the physiological quality of wheat seeds in response to the effects of years and sowing dates. in 2006 and 2007 seeds of the wheat cultivars cd 104, cd 105, cd 108, cd 110, cd 111 and cd 114 were sown on march 22nd, april 7th and 20th, may 4th and 18th, in the palotina region, paraná state. it was analysed the following traits: germination, seedling vigor classification and accelerated ageing. the data were subjected to joint variance analysis between the two years of the experiment and cultivars, sowing dates and years, for all combinations. the germination of the cultivars cd 105 and cd 108 were less influenced by sowing dates in both crop years. the results from germination tests, classification of seedling vigor and accelerated ageing showed that the sowing periods of march 22nd, april 7th and may 18th, in 2006, were not ideal for cultivars cd 110, cd 111 and cd 114. most sowing dates and cultivars in 2007 showed higher percentages of normal seedlings than for 2006. furthermore, most of the cultivars showed greater similarity between the years for the april 20th sowing date according to the results of the tests for germination and classification of seedling vigor.