气候变暖背景下亚热带地区三种常绿阔叶植物越冬策略研究 —— 基于叶绿体能量代谢

常绿植物冬季面临低温强光胁迫，导致叶绿体光能吸收和利用之间存在潜在能量失衡风险。目前，常绿植物越冬策略研究主要集中于温带及以北地区，主要是增强耐冻性或耐冷性。随着气候变暖，亚热带地区呈现冬季以零上低温为主，并伴随多次短期升温的气候现象，而对于气候变暖背景下生长于亚热带地区的常绿阔叶植物越冬策略研究较少。本项目针对气候变暖背景下亚热带地区气候特点，以广玉兰（冬季生长停滞，耐冷性强）、榕树（冬季生长停滞，冷敏感）、红叶石楠（冬季生长，耐冷性强）三种常绿阔叶植物为材料，从叶绿体能量代谢角度出发，分析越冬期前后季节变化、越冬期首次剧烈降温和越冬期内短期升温三种温度变化情况下，叶片捕光色素分子内禀特性、叶绿体光能吸收与电子传递、能量耗散途径和光合碳同化能力的响应规律，阐明这三种常绿阔叶植物在亚热带地区的越冬光保护机制及其对气候变暖的适应策略。

Evergreen are faced with the challenge of low temperatures in combination with high light exposure during winter. This combination of conditions can lead to a potentially dangerous imbalance between light absorption and its utilization via photosynthetic carbon assimilation in chloroplast. The researches of adaptive strategies in overwintering evergreens was focused on temperate-zone and its northern region perennials, which overwintering adpative strategies were mainly based on freeze tolerance or cold tolerance. Under the background of climate warming, the atmosphere of winter in the subtropical region is generally low temperature above zero degrees centigrade, and several short warming periods during winter are occurred. However, the overwintering adaptive strategies of evergreens in subtropical region under the background of climate warming have not been fully elucidated. In this project, we will take Magnolia grandiflora (winter dormancy type, cold-tolerance) , Ficus microcarpa (winter dormancy type, cold-sensitive) , and Photiniax fraseri (winter growth type, cold-tolerance) ,as materials to examine the changes of intrinsic characteristics of light-harvesting pigment molecules, chloroplastic light absorption and photosynthetic electron transport, energy dissipation pathways and carbon assimilation during winter period and winter before or after. The objective of the study is to investigate the overwintering adaptive strategies based on the chloroplastic energy metabolism of evergreens under the background of climate warming.