低温贮藏对琯溪蜜柚汁胞粒化与木质素代谢的影响

Effects of Low Temperature on the Relationship Between Granulation and Lignin Metabolism in Pummelo Fruit During Storage

以琯溪蜜柚果实为材料,分别在1、4、7℃和室温下贮藏琯溪蜜柚果实,探讨贮藏温度对汁胞粒化、木质素含量以及汁胞木质素代谢相关酶活性的影响。结果表明：木质素合成相关酶的活性在整个贮藏过程中逐渐升高,汁胞粒化指数和木质素含量也均随着贮藏时间的延长而增高;在4、7℃下贮藏时,汁胞木质素含量、粒化指数以及木质素合成相关酶PAL、CAD、PPO和POD的活性均显著低于室温和1℃;在不同的贮藏温度下,琯溪蜜柚汁胞粒化程度与汁胞中木质素含量均呈正相关的关系。因此,1℃的低温不适宜琯溪蜜柚的贮藏,而4~7℃较适宜琯溪蜜柚的贮藏。

To probe the effects of storage temperature on granulation index,lignin content and the enzymes activity,Guanximiyou [ Citrus grandis（L.） Osbeck cv.Guanximiyou] fruits stored at 1、 4、 7 ℃ and room temperature were used in the study.The index of granulation,contents of lignin and key enzymes of lignin biosynthesis including PAL,CAD,PPO and POD were detected.The results showed that the key enzymes of lignin biosynthesis,granulation index and lignin content were all increased during storage.The activities of PAL,CAD,PPO and POD stored in 4 ℃ and 7 ℃ were significantly lower than those stored in 1 ℃ and room temperature.The contents of lignin and granulation indices were also significantly lower than those under low temperature storage.According to the results,it was suggested that there was a positive correlation between granulation level and lignin content,the granulation was prevented through inhibiting the activities of key enzymes participated in lignin biosynthesis to reduce lignin content under 4 ℃ and 7 ℃ storage,but 1 ℃ was not suitable for pummelo storage.