干旱对不同种源花榈木幼苗生长及生理生化的影响  

Effects of drought on growth and physiological and biochemical characteristics of seedlings of Ormosia henryi from different provenances

作　　者：李天翔 肖亚琴 曹基武[1] 吴琴香[1] 杨骏[2] 吴小丽[2] LI Tianxiang;XIAO Yaqin;CAO Jiwu;WU Qinxiang;YANG Jun;WU Xiaoli(Central South University of Forestry&Technology,Changsha 410004,Hunan,China;Hunan Academy of Forestry,Changsha 410004,Hunan,China)

机构地区：[1]中南林业科技大学,湖南长沙410004 [2]湖南省林业科学院,湖南长沙410004

出　　处：《中南林业科技大学学报》2024年第12期86-96,共11页Journal of Central South University of Forestry & Technology

基　　金：中央财政林业草原生态保护恢复资金项目“国家珍稀树种花榈木等红豆树属种质资源收集及保育”(BH2023A001)。

摘　　要：【目的】研究干旱胁迫下不同种源花榈木幼苗生长和生理指标的响应机制,并对不同种源的抗旱性进行综合评价,以期为抗旱种源的筛选提供理论基础。【方法】收集3个不同地理种源的花榈木2年生实生苗:杭州市西湖区种源(XH)、宁波市余姚市种源(YY)、株洲市攸县种源(YX),设置4种干旱梯度进行为期1月的干旱胁迫试验:以田间最大持水量的80%~85%为水分对照组(CK),60%~65%为轻度干旱(LD),40%~45%为中度干旱(MD),30%~35%为重度干旱(HD),测定干旱胁迫下花榈木幼苗生长、生理生化等指标,并对不同种源花榈木抗旱性进行综合评价。【结果】1)在同一花榈木种源中,LD处理下幼苗株高和地径增量均比其他处理组大,其中余姚(YY)种源在LD处理条件下苗高增量和地径增量最大,分别为1.21 cm、1.57 mm;干旱条件下花榈木叶片比叶重及根冠比随干旱时间的延长呈增大的趋势,叶片含水率呈下降的趋势;2)花榈木叶片叶绿素a、叶绿素b及叶绿素总量随干旱胁迫的加重而逐渐降低,在干旱处理第10 d以后,叶绿素总含量下降幅度逐渐减小,变动范围为0.56~2.64 mg/g。干旱胁迫抑制花榈木的光合作用,降低其净光合速率和蒸腾速率,水分利用效率呈现先增大后减小的趋势,其中攸县(YX)种源在HD处理条件下水分利用效率最低,为0.14 mmol·m^(-2)·s^(-1);3)随着干旱胁迫的加重和持续,花榈木叶片中的丙二醛(MDA)含量逐渐升高,过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)等抗氧化酶活性在前期呈先上升后下降的趋势;4)隶属函数法对干旱胁迫下各种源花榈木2年生实生苗的生长、光合和生理指标进行综合评价,花榈木种源抗旱性依次为西湖(XH)>攸县(YX)>余姚(YY)。【结论】花榈木幼苗具有一定的抗旱能力,在干旱胁迫下,不同种源的花榈木幼苗在生长及生理生化指标中存在显著差异,综合评价的抗旱能力也�【Objective】The response mechanism of growth and physiological indices of different provenances of Ormosia henryi seedlings to drought stress was investigated,and the comprehensive evaluation of drought resistance among different provenances was conducted,aiming to provide a theoretical foundation for the selection of drought-resistant provenances.【Method】This study collected seedlings of O.henryi from three different provenances:Xihu District,Hangzhou(XH),Yuyao,Ningbo(YY),and Youxian,Zhuzhou(YX).Four drought gradients were set up for drought resistance test for 1 month:80%-85%of the maximum field water holding capacity as the control group(CK),60%-65%as mild drought(LD),40%-45%as moderate drought(MD),and 30%-35%as severe drought(HD).The growth,physiological,and biochemical indexes of O.henryi seedlings were measured under drought stress to comprehensively evaluate their drought resistance across different provenances.【Result】1)In the same provenance of O.henryi,seedlings under LD treatment exhibited greater height and diameter increments compared to those in other treatment groups.Furthermore,seedlings from the Yuyao(YY)provenance showed the largest height and diameter increments under LD treatment,measuring 1.21 cm and 1.57 mm.Under drought conditions,the leaf weight ratio and root shoot ratio increased with the extension of drought time,and the leaf water content decreased.2)The levels of chlorophyll a,chlorophyll b,and total chlorophyll in O.henryi leaves gradually decreased as drought stress intensified.Following 10 days of drought treatment,the reduction in total chlorophyll content showed a gradual decrease within the range of 0.56-2.64 mg/g.Drought stress inhibited photosynthesis in O.henryi,leading to a reduction in net photosynthetic rate and transpiration rate.Water use efficiency(WUE)initially increased and then decreased,with the lowest WUE recorded at 0.14 mmol·m^(-2)·s^(-1) in Youxian(YX)provenance under HD treatment.3)With increasing severity and duration of drought stress,malondialde

关 键 词：干旱胁迫 花榈木 不同种源 生长 光合特性 

分 类 号：S792.99[农业科学—林木遗传育种]