甜菜碱处理对西葫芦冷害及品质的影响
毕业论文关键词：甜菜碱；西葫芦；冷害；品质
Effects of Glycine Betaine Treatments on Chilling Injury and Quality of Summer Squash
Abstract：Due to the active metabolism, it is easy to result in rapid senescence after summer squash being picked and been preserved at normal temperature. While adopting the improper preservation method may cause chilling injury, which will reduce commodity value of the fruits. This paper researched about the effect of glycine betaine at different concentrations on chilling injury and quality of summer squash. The result showed that 10 mmo/L glycine betaine can protect cells from electrolyte leakage of plasma membrane groups, and restrain the enlargement of plasma membrane permeability to reduce the relative electrolytic leakage of samples. Meanwhile, it can slow down the decomposition of pericarp chlorophyll and efficiently inhibit the respiratory intensity of summer squash. What’s more, glycine betaine treatment can increase the activity of protective enzymes such as APX, CAT and SOD which contented in cells of summer squash, and reduce the production of active oxygens like O2•—, H2O2, etc., so that to maintain the metabolic balance of cell active oxygens, protect cytomembrane system, restrain the chilling injury on summer squash, and maintain the quality.
Key words: Glycine betaine; Summer squash; Chilling injury; quality
目 录
摘要1
关键词1
Abstract1
Key words1
引言（或绪论）1
1 材料与方法2
1.1 材料及处理 2
1.1.1 实验材料2
1.1.2 处理方法2
1.2 实验方法 2
1.2.1 冷害指数的测定2
1.2.2 呼吸强度的测定2
1.2.3 果皮相对电导率的测定2
1.2.4 果皮叶绿素含量的测定3
1.2.5 超氧阴离子产生速率的测定3
1.2.6 抗坏血酸过氧化物酶（APX）活性的测定3
1.2.7 过氧化氢酶（CAT）活性的测定3
1.2.8 超氧化物歧化酶（SOD）活性的测定3
2 结果与分析4
2.1 GB处理对西葫芦冷害指数的影响4
2.2 GB处理对西葫芦呼吸强度的影响4
2.3 GB处理对西葫芦果皮相对电导率的影响5
2.4 GB处理对西葫芦果皮叶绿素含量的影响5
2.5 GB处理对西葫芦超氧阴离子产生速率的影响6
2.6 GB处理对西葫芦APX活性的影响6
2.7 GB处理对西葫芦CAT活性的影响7
2.8 GB处理对西葫芦SOD活性的影响7
3 讨论8
3.1 GB处理对西葫芦品质的影响8
3.2 GB处理对西葫芦活性氧代谢的影响8
致谢9
参考文献9
甜菜碱处理对西葫芦冷害及品质的影响
西葫芦（Cucurbita pepo L.）又叫美洲南瓜，具有很高的营养价值，是瓜类蔬菜中总产量列前的主要商品蔬菜。西葫芦生长期气温极高，采后新陈代谢旺盛，常温下贮藏易导致营养品质严重流失，衰老较快[1]。通常低温贮藏被认为是果蔬保鲜最有效的方法之一，丁天[2]、龚国强等[3]指出，低温不仅能够抑制果蔬采后体内的呼吸代谢，而且有利于保持果蔬生理代谢及其营养物质的稳定性，从而达到延缓衰老，延长果蔬贮藏期的目的。但西葫芦是冷敏感型蔬菜，不适宜的低温贮藏易导致冷害[1]，造成严重的果肉腐烂，降低果实抗病性，导致品质劣变，严重影响商品价值。目前果蔬冷害的控制措施主要有间歇升温、低温预贮等物理方法和1-MCP、茉莉酸甲酯和甜菜碱试剂处理等化学方法[4]。