流动沙丘先锋植物沙米对风沙流和干旱胁迫的光合生理响应  

Photosynthetic Physiological Responses of the Pioneer Plant Agriophyllum squarrosum on Mobile Dune to Wind-sand and Drought Stress

作　　者：姜生秀[1] 赵鹏[1] JIANG Shengxiu;ZHAO Peng(State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating,Gansu Desert Control Research Institute,Lanzhou 730070,China)

机构地区：[1]甘肃省治沙研究所,甘肃省荒漠化与风沙灾害防治国家重点实验室[培育基地],兰州730070

出　　处：《西北植物学报》2022年第11期1910-1918,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：甘肃省青年科技基金计划(20JR5RA091)。

摘　　要：以民勤野外和盆栽沙米(Agriophyllum squarrosum)为研究对象,在自然条件下设置对照、挡风墙、浇水及浇水+挡风墙处理,在风洞内干旱和浇水环境下分别设置风速(0、6、8、10和14 m·s^(-1))和吹袭时间(0、15、30、45 min)处理,采用Li-6400便携式光合仪对沙米光合生理特征进行测定,探讨风沙流和干旱胁迫互作对沙米植株光合作用的影响。结果表明:(1)在野外自然条件下,沙米叶片P_(n)日进程在对照、设挡风墙、浇水处理均呈“双峰”曲线,而在设挡风墙+浇水处理呈“单峰”曲线,且设挡风墙处理峰值比对照增加,浇水处理的“午休”时间比对照推后;叶片G_(s)、T_(r)、WUE的日变化趋势与P_(n)基本相似,而C_(i)的日变化趋势则与P_(n)基本相反;沙米WUE日均值以设挡风墙处理最高,T_(r)日均值以浇水处理最高,P_(n)和G_(s)日均值均以设挡风墙+浇水处理最高。(2)在浇水条件下,沙米叶片的P_(n)、G_(s)在低速(6 m·s^(-1))风沙流胁迫下升高,后随着风速增大而减小,其T_(r)随风速的增大而增大,WUE则逐渐减小;在干旱条件下,沙米叶片P_(n)、G_(s)和WUE均随风速的增大而降低,其C_(i)和T_(r)则升高;在相同风速下,浇水处理叶片的P_(n)、G_(s)、T_(r)和WUE均不同程度高于干旱胁迫处理,而其C_(i)和WUE均与干旱胁迫处理接近。(3)沙米叶片的光合性能在浇水条件下遭受中速(8 m·s^(-1))风沙流吹袭45 min时显著降低,在干旱胁迫下遭受中速风沙流吹袭30 min时就显著降低。研究发现,干旱和风沙流胁迫均会抑制沙米进行光合作用,浇水和设挡风墙则可以提高沙米的光合性能;沙米的光合性能在浇水条件下受到低速风沙流胁迫的显著促进,在干旱胁迫下则随风速的增大而降低;浇水可以延长沙米光合作用对持续风沙流胁迫的耐受时间。Minqin field and potted Agriophyllum squarrosum were used as the research objects.The control,wind retaining wall,watering and watering+wind retaining wall treatments were set under natural conditions,and the wind speed(0,6,8,10 and 14 m·s^(-1))and the blowing time(0,15,30 and 45 min)were set under the drought and watering environments in the wind tunnel,respectively.To investigate the effects of wind-sand flow and drought stress on photosynthesis of A.squarrosum,we measured the photosynthetic physiological characteristics of A.squarrosum by LI-6400 portable photosynthetic apparatus.The results showed that:(1)under the natural field condition,the P_(n)diurnal progression of control,wind-retaining wall and watering treatments showed“double peak”curves,while it showed“single peak”curve in the wind-retaining wall+watering treatment.The peak value of wind-retaining wall was higher than that of the control,and the“lunch break”time of watering treatment was later than that of the control.The diurnal trends of G_(s),T_(r)and WUE were similar to those of P_(n),while the diurnal trends of C_(i)were opposite.The daily mean value of WUE was the highest in the retaining wall treatment,the daily mean value of T_(r)was the highest in the watering treatment,and the daily mean value of P_(n)and G_(s)were the highest in the retaining wall+watering treatment.(2)Under the watering condition,P_(n)and G_(s)increased under the low speed(6 m·s^(-1))sand flow stress,then decreased with the increase of wind speed,T_(r)increased with the increase of wind speed,and WUE decreased gradually.Under drought conditions,P_(n),G_(s)and WUE decreased with the increase of wind speed,while C_(i)and T_(r)increased.At the same wind speed,P_(n),G_(s),T_(r)and WUE of the watering treatment were higher than those of the drought stress treatment,while C_(i)and WUE of the watering treatment were same to those of the drought stress treatment.(3)The photosynthetic performance of A.squarrosum was significantly decreased when it was blown by mediu

关 键 词：沙米 风沙流 干旱胁迫 光合气体交换参数 

分 类 号：Q945.79[生物学—植物学]