Page 80 - 《广西植物》2026年第1期
P. 80

7 6                                    广  西  植  物                                         46 卷
               ( 1. Guangxi Forestry Research Instituteꎬ Guangxi Key Laboratory of Superior Timber Trees Resource Cultivationꎬ Nanning 530002ꎬ Chinaꎻ
                            2. Guangxi Zhuang Autonomous Region State ̄Owned Qipo Forest Farmꎬ Nanning 530034ꎬ China )

                 Abstract: In order to investigate the seed germination characteristics and physiological and biochemical characteristics of
                 Horsfieldia hainanensis seeds under high temperature and humidity ( HTH) stressꎬ in this paperꎬ the seeds of H.
                 hainanensis were used as the research objectsꎬ the seeds of H. hainanensis were treated with different high temperature
                 and humidity stress time (0ꎬ 1ꎬ 3ꎬ 5ꎬ 7 d). Then the indexes of seed germination and seedling growth were measuredꎬ
                 and the seed intracelluar substance and antioxidant enzyme activities of seeds were studied. The results were as follows:
                 (1) Compared with CKꎬ high temperature and humidity stress significantly inhibited seed germination percentage
                 (GP )ꎬ germination energy ( GE)ꎬ germination index ( GI) and vitality index ( VI)ꎬ and prolonged the mean
                 germination time ( MGT) of seeds. The cumulative germination rates of CKꎬ HTH ̄1ꎬ HTH ̄3ꎬ HTH ̄5 and HTH ̄7
                 treatments were 63.3%ꎬ 40.0%ꎬ 33.3%ꎬ 31.7% and 26.7%ꎬ respectively. High temperature and humidity significantly
                 inhibited plant height (PH)ꎬ root length (RL) and basal diameter (BD) growthꎬ and aboveground biomass (AB)ꎬ
                 underground biomass(UB) and root ̄shoot ratio(RSR) of seedlingsꎬ and HTH ̄7 was the lowest. (2) With the increase
                 of stress timeꎬ the contents of starch (St)ꎬ soluble sugar (SS)ꎬ soluble protein(SP)ꎬ and superoxide dismutase (SOD)
                 activity were significantly decreased compared with CKꎬ while the contents of peroxidase ( POD ) activityꎬ
                 malondialdehyde (MDA) and proline (Pro) were significantly increasedꎬ implying heightened oxidative stress and
                 membrane lipid peroxidationꎬ as well as an upregulated osmotic adjustment mechanism in response to stress. ( 3)
                 Correlation analysis showed that seed germination parameters (GPꎬ GEꎬ GIꎬ VI) and seedling growth indexes (PHꎬ
                 RLꎬ BDꎬ ABꎬ UBꎬ RSR) were positively correlated with SSꎬ SP and SODꎬ and negatively correlated with PODꎬ MDA
                 and Pro under high temperature and humidity stressꎬ indicating that oxidative damage and osmotic stress play crucial
                 roles in limiting seed vigor and seedling establishment. In conclusionꎬ with the prolongation of stress timeꎬ the
                 decomposition of seed intracelluar substancesꎬ the content of osmotic adjustment substancesꎬ the membrane lipid
                 peroxidation and the activity of antioxidant enzymes are increasedꎬ and the seed vitality and seedling growth are
                 inhibitedꎬ which provides a theoretical basis for the protection of H. hainanensis germplasm resources and the selection of
                 wilderness return environments return environment.
                 Key words: Horsfieldia hainanensisꎬ high temperature and humidityꎬ seed germinationꎬ antioxidant enzymeꎬ
                 intracelluar substancesꎬ osmotic adjustment substances




                温室气体排放导致全球气候变暖已被联合国                            humidityꎬHTH) 环境对植物种子的萌发具有重要
            政府 间 气 候 变 化 专 门 委 员 会 ( Intergovernmental         影响ꎮ 高温高湿环境加速种子老化进程ꎬ老化的
            Panel on Climate ChangeꎬIPCC)报道ꎮ 全球变暖不             种子 失 去 活 力ꎬ 表 现 出 低 萌 发 率 ( germination
            但增加 了 平 均 温 度ꎬ 而 且 缩 短 了 昼 间 温 度 范 围               percentageꎬGP)、萌发指数( germination indexꎬGI)
            (Footitt et al.ꎬ2018)ꎬ这导致极端高温天气频繁出                 和活力指数( vitality indexꎬVI) ( 贾梅花等ꎬ2021)ꎬ
            现ꎬ气候的这种变化将驱动植物种子休眠深度和                              并且对萌发胁迫的敏感性增加ꎬ这也反映在增加
            萌发时间变化ꎮ 植物生命的早期阶段ꎬ如萌发、幼                            的 种 子 平 均 萌 发 时 间 ( mean germination timeꎬ
            苗发育和早期生长ꎬ同时受到内部生理生化调控                              MGT)上ꎬ从而导致幼苗个体更小( Gokdas et al.ꎬ
            和外部环境因素的影响ꎬ是植物生长对外界刺激                              2022)ꎮ 此外ꎬ种子的老化还可能导致不可逆的代
            最为敏感的阶段( Ma et al.ꎬ2024)ꎮ 大量研究表                    谢和细胞变化ꎬ如抗氧化能力降低、质膜损伤、营
            明ꎬ温度和湿度是影响种子萌发的重要环境因子                              养物质耗尽和遗传物质的破坏( McDonaldꎬ1999)
            (Bore et al.ꎬ2023ꎻ孙宜等ꎬ2023)ꎮ 温度和湿度通                等ꎮ 在热带或亚热带地区ꎬ高温高湿不仅出现长
            过调控萌发过程中各种生理活动的酶活性、膜稳                              时间季节性波动ꎬ短时胁迫(0 ~ 7 d)ꎬ也会影响植
            定性以及通透性等直接影响种子萌发进程ꎮ 在热                             物生长ꎬ特别是种子萌发的敏感时期ꎮ 研究表明ꎬ
            带或亚热带生境中ꎬ高温高湿(high temperature and                 随胁迫时间延长ꎬ种子活力降低( 宋丽媛ꎬ2023)ꎬ
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