摘要
为了探究长期干旱胁迫下连翘不同器官的非结构性碳水化合物(NSC)含量与水力特性的协调及响应机制。以连续3年不同水分条件处理后的连翘幼苗为研究对象,设置3个水分处理(适宜供水、中度干旱胁迫和重度干旱胁迫),研究长期干旱胁迫后连翘幼苗的光合特性、生物量的分配、NSC各组分含量、水力特性的变化及其碳水两者之间的相关关系。结果表明:(1)适宜供水、中度干旱、重度干旱胁迫下,枝条的栓塞程度分别为30.7%、41.8%和42.3%,枝条导水率分别为0.95、0.71、0.65 kg m^(-1)s-1MPa^(-1)。(2)重度干旱胁迫显著降低了净光合速率、蒸腾速率、气孔导度、水分利用效率。(3)重度干旱胁迫导致地上和粗根生物量显著降低,细根生物量和根冠比显著增加。此外,各器官的NSC含量显著降低,其根系NSC消耗量最高,根系的可溶性总糖和淀粉含量显著降低,枝条的可溶性总糖、葡萄糖和蔗糖含量增加了12.9%、31.1%和45.7%,而淀粉含量降低了40.7%。(4)枝条栓塞程度和导水率与可溶性总糖、淀粉、蔗糖和葡萄糖含量显著相关,其栓塞程度与可溶性总糖、葡萄糖和蔗糖呈正相关,而与淀粉呈负相关(P<0.01)。综上所述,干旱导致连翘枝条木质部的栓塞程度增加,导水率、光合作用和水分运输效率均显著降低,但连翘通过提高枝条内可溶性总糖、葡萄糖、蔗糖含量和降低淀粉、NSC含量以提高植物在干旱条件下的存活机率及旱后水分恢复能力,研究为半干旱区连翘培育和经营提供理论依据。
This paper aims to investigate the coordination and response mechanism of non-structural carbohydrate(NSC)content and its hydraulic characteristics in various organs of F.suspensa seedings during a prolonged period of drought stress.We exposed F.suspensa seedings to various degrees of drought treatments(CK,appropriate water supply;MS,moderate drought stress;and SS,severe drought stress)for three consecutive years.The changes in photosynthetic characteristics,the accumulation of biomass,the distribution of NSC,and the function of hydraulics in the various organs were measured under a prolonged period of drought stress.The carbon-water coordination of those indicators was also discussion in this paper.The results found that:(1)the‘native’embolism of branches was 30.7%,41.8%and 42.3%,respectively,under appropriate water supply,moderate drought stress,and severe drought stress.While the hydraulic conductivity of branches was 0.95,0.71 and 0.65kg m^(-1) s-1 MPa^(-1),respectively.(2)The net photosynthetic rate,transpiration rate,stomatal conductance,and water usage efficiency were all dramatically decreased after a prolonged period of severe drought stress.(3)Under severe drought stress,the fine root biomass and the root-to-shoot ratio significantly increased,while aboveground and coarse root biomass decreased significantly.In addition,the content of NSC each organ decreased significantly,with the highest NSC consumption in root system.The total soluble sugar and starch content of the root system significantly dropped,while the total soluble sugar glucose and sucrose content of the branches significantly increased by 12.9%,31.1%and 45.7%,while the starch content significantly decreased by 40.7%.(4)The‘native’embolism and hydraulic conductivity of branches was significantly correlated with the content of total soluble sugar,starch,sucrose,and glucose content(P<0.01),and the‘native’of embolism of branches was a significant positive correlation with total soluble sugar,glucose,and sucrose content.In additional
作者
王云霞
刘莹
付雨辰
李欣诺
刘青
马辉珍
何俐蓉
王国梁
WANG Yunxia;LIU Ying;FU Yuchen;LI Xinnuo;LIU Qing;MA Huizhen;HE Lirong;WANG Guoliang(College of Soil and Water Conservation Science and Engineering,Northwest Agriculture and Forestry University,Yangling 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,China;College of Resources and Environment,Northwest Agriculture and Forestry University,Yangling 712100,China;College of Life Sciences,Northwest Agriculture and Forestry University,Yangling 712100,China)
出处
《生态学报》
CAS
CSCD
北大核心
2024年第11期4698-4707,共10页
Acta Ecologica Sinica
基金
国家重点研发计划项目(2022YFF1300400)
国家自然科学基金项目(42130717)
国家自然科学基金项目(42007062)。
关键词
干旱
渗透调节
非结构碳水化合物
水力特性
drought
osmotic regulation
non-structural carbohydrate
hydraulic characteristics
