菜心采后褪黑素处理的低温保鲜效果分析

为了延长采后菜心的货架期,保持低温下的贮藏品质,用褪黑素对菜心进行了采后处理。将菜心采后分别喷洒50、100 mg/L褪黑素水溶液,以清水处理作为对照,在4 ℃下进行低温贮藏,观察菜心外观品质变化并测定品质相关的生理生化指标。结果表明：4 ℃条件下,褪黑素延缓了菜心叶片叶绿素降解,使茎、叶组织保持了较高可溶性糖和可溶性蛋白含量,减少丙二醛积累,提高了采后菜心组织内超氧化物歧化酶和过氧化物酶活性,同时褪黑素处理降低了采后菜心木质素含量,抑制了肉桂醇脱氢酶BcCAD4和BcCAD5基因的表达,推测褪黑素的作用效果可能与抑制肉桂醇脱氢酶基因的表达相关。

Effect of Melatonin Treatment on the Preservation of the Flower Stalk of Brassica campestris L. ssp. chinesis var. utilis Tsen et Lee after Harvest Under Low Temperature

In order to extend the shelf-life and maintain the postharvest quality of flowering Chinese cabbage (FCC)(Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) under low temperature, the flower stalks harvested of FCC were treated with 50, 100 mg/L melatonin respectively, stored at 4 ℃, then the appearance quality was observed, physiological and biochemical indexes related to stored quality were evaluated during storage. The degradation of chlorophyll of the leaves was delayed by melatonin treatment. Much higher levels of soluble sugar and soluble protein content were maintained than the control. Activities of superoxide dismutase and peroxidase were improved under at storage temperature 4 ℃. Meanwhile the content of lignin of the stalk and the expression of cinnamyl alcohol dehydrogenase gene BcCAD4 and BcCAD5 related to lignin synthesis was suppressed by the melatonin treatment. It indicated that the effect of melatonin treatment may be related to the inhibition of the expression of cinnamol dehydrogenase genes.