达乌里胡枝子(Lespedeza davurica)混播下叶绿素荧光特性对水分变化的响应  

Response of Chlorophyll Fluorescence Characteristics of Lespedeza davurica to Water Change in Mixtures

作　　者：黄瑾[1] 徐伟洲[2] 王智 孟令超 马威 Huang Jin;Xu Weizhou;Wang Zhi;Meng Lingchao;Ma Wei(Institute of Soil and Water Conservation,Northwest A&F University,Yangling,712100;College of Life Science,Yulin University,Yulin,719000)

机构地区：[1]西北农林科技大学,水土保持研究所,杨凌712100 [2]榆林学院生命科学学院,榆林719000

出　　处：《分子植物育种》2019年第20期6918-6930,共13页Molecular Plant Breeding

基　　金：国家自然科学基金青年科学基金项目(41701602);榆林学院博士科研启动基金项目(16GK04)共同资助

摘　　要：为研究黄土丘陵区白羊草植物群落优势种叶绿素荧光动态变化特性对土壤水分变化的响应,采用盆栽控制试验,设置7个组合比例(白羊草∶达乌里胡枝子, 0∶12, 2∶10, 4∶8, 6∶6, 8∶4, 10∶2和12∶0)和3种水分水平(高水(HW),中水(MW)和低水(LW),对应为田间持水量的80%±5%, 60%±5%和40%±5%),并分别在达乌里胡枝子现蕾期、开花期与结实期将土壤水分从高水降到中水(H-MW)和低水(H-LW),测定了达乌里胡枝子在水分降低后第0天、第1天、第3天、第7天的叶绿素荧光参数。结果表明:在土壤水分阶段干旱胁迫后,最大光化学效率(Fv/Fm)和实际光化学效率(ФPSⅡ)总体上在开花期显著最高、结实期显著最低,且Fv/Fm变化范围为0.767~0.829,表明达乌里胡枝子具有更为稳定的光化学效率;现蕾期和开花期的ФPSⅡ均以H-MW显著高于H-LW,表明土壤水分降低幅度较大显著削弱PSⅡ反应中心的实际光能捕获效率;开花期的非光化学淬灭系数(NPQ)为H-LW显著高于H-MW,表明达乌里胡枝子开花期通过耗散过剩激发能以减轻重度水分胁迫对叶片光合结构的损伤;单播下的Fv/Fm、ФPSⅡ和光化学淬灭系数(q P)显著高于或与混播无显著差异,表明混播对土壤水分阶段降低后达乌里胡枝子的光合反应过程产生抑制作用。本研究为阐明土壤水分变化条件下两草种竞争与共生的生理生态机制提供理论依据。In order to clarify the dynamic changes of chlorophyll fluorescence characteristics of dominant species in response to soil water periodical change in Bothriochloa ischaemum communities, seven mixture ratios(B.ischaemum∶ L. davurica, 0∶12, 2∶10, 4∶8, 6∶6, 8∶4, 10∶2 and 12∶0) and three soil water regimes(HW 80%±5% of field capacity(FC), MW 60%±5% of FC, LW 40%±5% of FC) were set in the pot experiment, and soil water content was reduced separately from HW to MW(H-MW) or from HW to LW(H-LW) during the budding period, flowering period and mature period of L. davurica, respectively. Chlorophyll fluorescence parameters of L. davurica were measured in 0, 1 d, 3 d, 5 d, 7 d after soil water reduced. The results showed that under the soil water periodical drought conditions, the maximum photochemical efficiency(Fv/Fm) and active photochemical efficiency(ФPSⅡ) of L. davurica in the budding period, flowering period were significantly higher than mature period, and the values of Fv/Fm ranged from 0.767 to 0.829, which indicated that L. davurica had more stable photochemical efficiency.ФPSⅡ of L. davurica in the budding period and flowering period were significantly higher under H-MW than H-LW regime, indicate that the active photochemical efficiency of the PSⅡ reaction center has been weakened when the soil water reduce intensity was stronger. NPQ of L. davurica in the flowering period was significantly higher under H-LW than H-MW regime, which illustrated that L. davurica in the flowering period protected the photosynthetic apparatus by dissipating the excess solar energy under sever water stress. Generally, Fv/Fm, ФPS Ⅱand qP of L.davurica in monoculture were higher or comparable than in mixtures, which suggested that mixture planting limited the photosynthetic reaction process of L. davurica after soil water periodical reduced. The results of the study will contribute to identify the co-existence and competition mechanisms of both co-occurring species under soil water periodical change condit

关 键 词：达乌里胡枝子(Lespedeza davurica) 混播 叶绿素荧光特性 水分变化 

分 类 号：S51[农业科学—作物学]