| 摘要: |
| 为探究不同红光/远红光（R/FR）比值对双断根西瓜嫁接苗生理及光合荧光特性的影响，提高西瓜嫁接苗种苗品质，对双断根西瓜嫁接苗进行不同光质处理，共设置4种光质组合：黑暗（D）、白光（W）、高比值R/FR（R/FR=3，H）和低比值R/FR（R/FR=0.3，L），以黑暗为对照，分析西瓜嫁接苗幼苗形态、渗透调节物质、抗氧化酶系统和光合荧光特性。结果表明：与对照相比，L处理显著提高了西瓜嫁接苗的成活率和生长指标，显著提高接穗叶片中的抗氧化酶活性（SOD和POD）、可溶性糖和可溶性蛋白质量分数，同时显著降低了O2-、H2O2和MDA的积累。L处理对西瓜嫁接苗光合系统也有一定影响：处理8 d时，嫁接苗光合特性指标、Fv/Fm、Fv'/Fm'和ФPSII显著升高，NPQ显著下降；而长时间处理（20 d）会导致叶绿素质量分数以及光合特性指标降低，Fv/Fm、Fv'/Fm'、ФPSII和qP下降，NPQ显著升高。综上，低比值R/FR处理能够通过增强西瓜嫁接苗抗氧化能力并影响光合作用的过程，最终促进双断根西瓜嫁接苗的成活及生长。 |
| 关键词: 双断根嫁接 西瓜 红光/远红光 抗氧化系统 光合系统 |
| DOI：10.11841/j.issn.1007-4333.2024.03.08 |
| 投稿时间：2023-07-06 |
| 基金项目:江苏省重点研发现代农业项目（BE2021379）；青海省重点研发与转化计划项目（2022NK121）；山西省重点研发计划项目（202102140601013）；山西省基础研究计划项目（202203021211263） |
|
| Effects of different R/FR ratios on physiological and photosynthetic fluorescence characteristics of double-root-cutting grafted watermelon seedlings |
|
WANG Yaya1,2, ZHANG Fan1, SHI Yu1, BAO Encai2, CAO Kai2, WU Xue2*, ZHANG Yi1*
|
| (1.College of Horticulture, Shanxi Agricultural University, Taigu 030801, China;2.Institute of Agricultural Facilities and Equipment, Jiangsu Academy of Agricultural Sciences/Key Laboratory of Facility Agricultural Engineering in the Middle and Lower reaches of Yangtze River, Ministry of Agriculture and Rural Affairs, Nanjing 210014, China) |
| Abstract: |
| To investigate the effects of different R/FR ratios on the growth and physiological indices and improve the quality of seedlings， different lights were used to illuminate double-root-cutting grafted watermelon seedlings. Four light quality combinations were set as follows： Dark （D）， White light （W）， High ratio R/FR （R/FR=3， H） and Low ratio R/FR （R/FR=0.3， L）. The morphology， osmoregulatory substances， antioxidant enzyme system and photosynthetic fluorescence characteristics of watermelon grafted seedlings were analyzed using darkness as a control. The results showed that compared with the controlL treatmentcould significantly improve the survival rate and growth indicators of grafted seedlings， significantly increasethe antioxidant enzyme activities （SOD and POD）， soluble sugar and soluble protein mass fractions in the scion leaves， and significantly reduce the accumulation of O2-， H2O2 and MDA. L treatment also had certain effects on the photosynthetic system of watermelon grafted seedlings. After 8 d of treatment， the photosynthetic characteristic indicators， Fv/Fm， Fv′/Fm′ and ФPSII of grafted seedlings were significantly increased and NPQ was significantly decreased. However， long-term treatment （20 d） can lead to a decrease inchlorophyll mass fraction and photosynthetic characteristic indicators including Fv/Fm， Fv′/Fm′， ФPSII and qP， while NPQ was significantly increased. In summary， low ratio R/FR treatment can enhance the antioxidant capacity of watermelon grafted seedlings and affect the process of photosynthesis， ultimately promoting the survival and growth of double-root-cutting grafted watermelon seedlings. |
| Key words: double-root-cutting grafting watermelon R/FR antioxidant system photosystem |
