《植物生理学报》 2018, 54(5): 895-903

水分胁迫下嫁接对杭白菊渗透调节物质及相关代谢酶基因表达的影响

陈月, 孙宪芝^*, 杨景慧, 张胜, 郑成淑

山东农业大学园艺科学与工程学院/作物生物学国家重点实验室, 山东泰安271018

通信作者：孙宪芝；E-mail: sunxianzhi@126.com

摘　要：

以盆栽的杭白菊嫁接苗与扦插苗为材料, 采用自然干旱的方法, 研究水分胁迫下嫁接对杭白菊叶片渗透调节物质及其代谢关键酶相关基因的表达规律。结果表明, 水分胁迫抑制了杭白菊的生长, 但嫁接苗可保持较高根系生长量, 进而保持较高的叶片含水量和叶片干重, 缓解水分胁迫对植株生长的抑制程度。在水分胁迫下, 杭白菊叶片活性氧含量、相对电导率和丙二醛含量呈上升趋势, 而嫁接苗缓解活性氧胁迫, 减轻细胞膜脂质过氧化, 降低细胞膜受伤害程度。水分胁迫前期, 扦插苗CmP5CR、CmP5CS和Cmδ-OAT基因表达量上调, 促进脯氨酸较早积累; 同时CmNI、CmAI和CmSPS基因表达量上调, 导致可溶性糖含量增加, 进而说明杭白菊扦插苗对水分胁迫更加敏感。极度水分胁迫下, 与扦插苗相比, 嫁接苗CmP5CS基因表达上调, 抑制CmProDH基因表达, 保持相对较高的CmNI和CmSPS基因表达量, 以维持较高的可溶性糖和脯氨酸合成能力, 保证渗透调节的正常进行。短期水分胁迫条件下, 嫁接有利于提高杭白菊的耐旱性。

关键词：嫁接; 杭白菊; 水分胁迫; 渗透调节; 基因表达

收稿：2017-11-03   修定：2018-04-20

资助：国家自然科学基金(31101564)。

Effect of grafting on osmolytes and expression of related metabolic enzyme genes in chrysanthemum under water stress

CHEN Yue, SUN Xian-Zhi^*, YANG Jing-Hui, ZHANG Sheng, ZHENG Cheng-Shu

College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an, Shandong 271018, China

Corresponding author: SUN Xian-Zhi; E-mail: sunxianzhi@126.com

Abstract:

The effects of grafting on osmoregulation substances and the expression of metabolic-related genes in chrysanthemum were investigated with potted grafted and cutting plants under natural water stress. The results suggested that the growth of the plants were inhibited under water stress. The grafted plants exhibited higher roots growth, leaf water content and leaf dry weight, suggesting that the grafting could alleviate growth inhibition under water stress. Water stress induced a significant increase in the content of active oxygen, the relative conductivity and malondialdehyde, but these effects were alleviated by the grafting. The grafted plants could relieve the reactive oxygen stress and reduce lipid peroxidation of cell membrane against the damage of cell membrane by water stress. In the cutting plants, the increased proline content was apparently associated with increased mRNA levels of CmP5CR, CmP5CS and Cmδ-OAT at early period of water stress. Meanwhile, the expression of CmNI, CmAI and CmSPS were higher than those in the grafted plants which prompted the accumulation of the soluble sugar. It showed that the cutting plants were more sensitive to water stress. Compared with cutting plants, a significant up-regulation in the expression of CmP5CS, CmNI and CmSPS, as well as a significant inhibition in the expression of CmProDH were observed in grafted plants. It is inferred that higher osmotic regulation in the grafted plants owed to the higher soluble sugar and proline synthesis capacity. These results suggest that grafting is beneficial to improve the drought resistance of chrysanthemum under short-term water stress.

Key words: grafted; chrysanthemum; water stress; osmolytes; genes expression