文献类型： 外文期刊

作者： Peng, Ying ¹ ; Tong, Hui ¹ ; Yuan, Ye ² ; Yuan, Zuhua ¹ ; Hu, Xinjun ¹ ; Yin, Wuping ¹ ;

作者机构： 1.Hunan Acad Agr Sci, Hunan Vegetable Res Inst, Changsha 410125, Peoples R China

2.Yuelushan Lab, Changsha 410128, Peoples R China

3.Hunan Acad Agr Sci, Hunan Inst Agr Environm & Ecol, Changsha 410125, Peoples R China

关键词： antioxidant enzyme activity; bitter gourd; chlorophyll fl uorescence; grafting; low-temperature stress; pumpkin rootstock

期刊名称：HORTSCIENCE （ 影响因子：1.6； 五年影响因子：1.9 ）

ISSN： 0018-5345

年卷期： 2025 年 60 卷 1 期

页码：

收录情况： SCI

摘要： Bitter gourd (Momordica charantia L.) is one of the Cucurbitaceae species that is sensitive to low temperatures. Grafting onto pumpkin rootstock is an effective technique to increase the chilling tolerance of the Cucurbitaceae species upon exposure to lowtemperature stress. However, research on the mechanism by which pumpkin rootstock increases chilling tolerance of bitter gourd remains limited. In this study, bitter gourd 'Baoyu No.2' was used as the scion, and pumpkin 'Dongfang Changsheng' served as the rootstock; self-rooted seedlings are used as a control. The grafted and self-rooted bitter gourd seedlings were exposed to low-temperature stress (10 degrees C) for 10 days and allowed to recover stance contents, antioxidant enzyme activity, and chlorophyll fluorescence induction kinetics were determined. We found that the malondialdehyde (MDA) and proline (PRO) levels in the leaves of both self-rooted and grafted bitter gourd seedlings, as well as the activity of antioxidant enzymes, including superoxide dismutase (SOD) and peroxidase (POD), tended to increase overall with increasing duration of low-temperature stress. After 10 days of low-temperature stress, the PRO content of grafted seedlings increased by 312.77% compared with the self-rooted seedlings. The SOD activity increased by 46.19%, and the POD activity increased by 4.66%. Under low-temperature stress, the chlorophyll fluorescence induction kinetics (OJIP) curves of both self-rooted and grafted seedlings clearly changed. As the low-temperature stress duration increased, the maximum fluorescence intensity (P) decreased compared with 0 day, and the J-I-P curve tended to flatten. However, the decline and flattening for grafted seedlings were weaker than those for self-rooted seedlings. After 3 days of low-temperature stress, the Fv/Fm of the self-rooted seedlings reached its lowest point of 0.63, which was 24.10% lower and 18.18% lower than that noted at 0 day and for the grafted seedlings, respectively. The PIABS of the self-rooted seedlings reached its lowest point of 0.61, which was 86.76% lower than that noted at 0 day and 68.88% lower than the grafted seedlings. Furthermore, after 3 days of low-temperature stress, the absorption per active reaction center (ABS/RC) of the self-rooted seedlings increased by 25.19% compared with 0 day and 26.54% compared with the grafted seedlings. Moreover, the dissipation energy per active reaction center (DIo/RC) of the self-rooted seedlings was 179.43% of that noted at 0 day and 108.45% greater than that of the grafted seedlings.