Physiological and biochemical changes in lettuce seeds during storage at different temperatures

Resumo

Dormancy in lettuce seeds is a process that is not yet fully understood. High temperatures germination and storage can cause seed dormancy promoting physiological and enzymatic changes. The goal of this study was to investigate the influence of the period and storage environments on the quality and numbness of different lettuce cultivars. Also investigate the biochemical changes. A completely randomized experimental design was used in a 4x8x3 factorial arrangement to evaluate physiological quality in different storage periods and environments for lettuce seeds from eight cultivars. The biochemical activity was assessed by tetrazolium test and the activity of the endo-β-mannanase. There are physiological and biochemical changes in lettuce seeds under period and high temperatures storage environment. There is a reduction of seed quality at high storage temperatures mainly to 120 days. The tetrazolium test indicates that the seeds were viable. However there was no germination at high temperatures. There was a decrease in the expression of endo-β-mannanase enzyme being influenced by the environment and storage period. The Everglades cultivar is thermotolerant.