Análise de imagens na avaliação do potencial fisiológico de sementes de milho

Abstract

Image analysis of seedlings is a technique with potential for fast assessment of physiological seed quality, with accurate and often non-destructive results. The Seed Analysis System (SAS) is image analysis equipment for seeds and seedlings with potential use in quality control of seeds as a vigor test. The aim of this study was to define an optimal methodology for image analysis of corn seedlings using the SAS equipment and to verify potential use of the equipment in evaluation of the physiological potential of maize seeds. We used 9 lots of seeds from 2 maize hybrids characterized by the following tests: first germination count, germination, accelerated aging test, cold test, seedling emergence test at the controlled temperatures of 25ºC and 30ºC, and the seedling emergence speed index. The image analysis experiment was performed in a 9 x 4 factorial arrangement (9 lots x 4 methods of image analysis of seedlings -with and without the blue TNT substrate, and with and without manual image correction). The seedlings were evaluated by mean length of the coleoptile, root and and the seedling itself, and by indexes of automatic and manual vigor, uniformity and growth, provided by the SAS equipment. The use of blue TNT as an image contrast in the germination test interferes in the initial development of maize seedlings. Maize seed vigor may be evaluated from seedlings obtained from sowing on a white paper towel at a temperature of 25°C on the third day. Image analysis should be performed with automatic calibration using SAS software, without the need for correction of seedling images. SAS is a promising piece of equipment for assessing the physiological potential of maize seeds.