甘肃农业大学干旱生境作物学重点实验室开放基金课题资助(GSCS-2021-04)；甘肃省自然科学基金重点项目(21JR7RA803)。

探究不同钙水平对娃娃菜生长发育和活性氧代谢的影响，为揭示娃娃菜的需钙特性、生态适应性和养分管理提供理论依据。以钙敏型‘秋玉黄’和钙耐受型‘华耐B1102’两个品种作为试材，采用基质（蛭石∶珍珠岩=3∶1）盆栽方法，共设置5个钙水平（0 mmol/L、2 mmol/L、4 mmol/L、6 mmol/L、8 mmol/L），研究不同钙水平对两种娃娃菜生长、干物质积累、ROS含量、丙二醛(MDA)含量以及相关抗氧化酶活性的影响。两种娃娃菜对钙水平的响应程度不同，‘秋玉黄’的叶宽、根鲜质量、地上部鲜质量、结球率、单球质量、总根表面积和根系活力均在6 mmol/L的钙水平下达到最大，其中根鲜质量和地上部鲜质量较不施钙显著增加37.9% 和29.8%，与8 mmol/L的钙水平之间无显著差异。叶片中MDA、H₂O₂和O^-·₂含量在6 mmol/L的钙水平下最低，但是SOD、POD和CAT等抗氧化酶活性最高，说明缺钙和高钙均会对娃娃菜造成不同程度的胁迫。‘华耐B1102’的叶宽、根鲜质量、地上部鲜质量、结球率、单球质量、总根表面积和根系活力均在4 mmol/L 的钙水平下达到最大，地上部鲜质量显著增加，较无钙处理增加64.33%。叶片中MDA、H₂O₂和O^-·₂含量在4、6 mmol/L的钙水平下最低，但是SOD、POD和CAT等抗氧化酶活性最高，也说明缺钙和高钙均会对娃娃菜造成不同程度的胁迫。娃娃菜对钙的需求量高，缺钙会导致干烧心，无法结球。缺钙或供钙水平过高会降低娃娃菜细胞保护酶活性及根系活力，但对高钙具有一定的适应能力。不同品种对钙水平的适应性不同，6 mmol/L钙水平适宜敏感型品种‘秋玉黄’的生长，4 mmol/L钙水平适宜耐受型品种‘华耐B1102’的生长。

Effects of Different Calcium Levels on Growth and Active Oxygen Metabolism of Mini Chinese Cabbage

To investigate the effects of different calcium levels on the growth,development,and metabolism of active oxygen of mini Chinese cabbage,this study aims to provide a theoretical basis for understanding calcium demand characteristics, ecological adaptability and nutrient management of mini Chinese cabbage.Two varieties,namely the calcium-sensitive ‘Qiuyuhuang’ and the calcium-tolerant ‘Huanai B1102,’ were selected as materials.In a pot culture with a substrate mix of vermiculite and perlite in a 3∶1 ratio, five different calcium levels(0 mmol/L,2 mmol/L,4 mmol/L, 6 mmol/L, and 8 mmol/L) were established..The study explored the effects of different calcium levels on the growth, dry matter accumulation, ROS content, malondialdehyde content and the activities of related antioxidant enzymes in these two mini Chinese cabbage varieties .The results showed that the response of the two varieties of mini Chinese cabbage to the calcium level was different.The leaf width, root fresh mass , shoot fresh mass , heading rate, single head mass , total root surface area and root activity of the ‘Qiuyuhuang’ reached the maximum at the calcium level of 6 mmol/L.The root fresh mass and shoot fresh mass significantly increased by 37.9% and 29.8%,respectively, compared with the calcium level without calcium application, and there was no significant difference between the calcium level of 8 mmol/L.The contents of MDA, H₂O₂ and O^-·₂ in leaves were the lowest at the calcium level of 6 mmol/L, but the activities of antioxidant enzymes such as SOD, POD and CAT were the highest, indicating that calcium deficiency and high calcium will cause different degrees of stress on the leaf width, root fresh mass , shoot fresh mass , heading rate, single head mass , total root surface area and root activity in‘Huanai B1102’ ,which reached the maximum at the calcium level of 4 mmol/L .The shoot fresh mass increased significantly, which was 64.33% higher than that of non-calcium treatment.The contents of MDA, H₂O₂ and O^-·₂ in leaves were the lowest at the calcium level of 4 and 6 mmol/L, but the activities of antioxidant enzymes such as SOD, POD and CAT were the highest, the calcium deficiency and high calcium would cause different degrees of stress on mini Chinese cabbage.Mini Chinese cabbage has a high demand for calcium, and lack of calcium will lead to dry heartburn, unable to form balls, and has a certain adaptability to high calcium.Calcium deficiency or too high calcium supply level reduces the activity of cytoprotective enzymes and reduces the activity of root system.Different varieties have different adaptability to calcium level.6 mmol/L calcium level is suitable for the growth of sensitive variety ‘Qiuyuhuang’, and 4 mmol/L calcium level is suitable for the growth of tolerant variety ‘Huanai B1102’.The results provide a theoretical foundation for the calcium requirement characteristics and calcium fertilizer management of mini Chinese vegetable.