PHYSIOLOGICAL AND ENZYME ACTIVITY CHANGES IN STORED SEEDS OF Melanoxylon brauna Schott.

Temperature and relative humidity set the basic conditions for the preservation of recalcitrant and orthodox seeds. The seed conservation of braúna under relative humidities of 55, 75 and 93% at 20°C was performed with the aim of evaluating germination and vigor responses, relating them to the membrane permeability, enzyme activity, content and lipid peroxidation. Increasing environment water content decreases seed quality and also decreases the activity of the enzymes superoxide dismutase and catalase, and increases activity of glucose-6-phosphate dehydrogenase. The membrane permeability increases with increasing deterioration of the seeds. There is no relationship between the changes in lipids content and peroxidation and seed deterioration.

温度与相对湿度是顽拗型（recalcitrant）种子与正常型（orthodox）种子保存的基础条件。本研究于20℃、相对湿度分别为55%、75%与93%的条件下开展braúna种子的保存实验，旨在评估其发芽与活力响应，并将该响应与细胞膜透性（membrane permeability）、酶活性、脂质含量及脂质过氧化（lipid peroxidation）相关联。环境含水量升高会降低种子品质，同时抑制超氧化物歧化酶（superoxide dismutase）与过氧化氢酶（catalase）的活性，并提升葡萄糖-6-磷酸脱氢酶（glucose-6-phosphate dehydrogenase）的活性。细胞膜透性随种子劣变程度加剧而升高。脂质含量与过氧化反应的变化与种子劣变之间并无关联。