摘要
采用转基因(PSAG12-ipt)非洲菊为材料,研究干旱胁迫对叶绿素荧光和光合作用的影响。结果发现,随着干旱胁迫加剧,PSⅡ电子传递量子效率(ΦPSⅡ)、开放的PSⅡ反应中心捕获激发能效率(Fv’/Fm’)、光化学猝灭系数(qP)、表观光合电子传递速率(ETR)都表现出降低的趋势,光化学反应的能量(P)在叶片所吸收的光能中所占的比例也逐渐减少,净光合速率(Pn)、气孔导度(Gs)也出现同样下降的趋势。随着干旱胁迫的解除,ΦPSⅡ、Fv’/Fm’、qP、ETR、Pn、Gs都显著上升,缓慢恢复。转基因植株与非转基因对照相比,叶绿素荧光参数和光合作用参数的变化幅度较小,在干旱胁迫下各项参数下降较慢,干旱胁迫结束后各项参数恢复较快。在干旱胁迫和恢复过程中,P在光能分配中所占的比例,转基因植株大于对照。反应中心由非光化学反应耗散的能量(E)在干旱胁迫过程和恢复过程中没有明显的变化。
The chlorophyll fluorescence parameters （ actual quantum yield of PS Ⅱ photochemistry, φPS Ⅱ ; quantum efficiency of open PS Ⅱ reaction centers, Fv＇/Fm＇ ; photochemical quenching coefficient, qP; electron transport rate, ETR） and photosynthesis parameters （net photosynthetic rate, Pn; stomatal conductance, Gs） of the gerbera modified by PSAG12-ipt were investigated under drought stress. The results showed that φPS Ⅱ, Fv＇/Fm＇, qP, ETR, Pn and Gs decreased after drought stress and gradually increased after watering recovery. However, these decreases caused by drought stress were lower in the modified gerbera than in the wild type. The modified gerbera showed a higher tolerance to drought stress. The fraction of absorbed light in photochemistry （P） decreased under drought stress, but being higher in the modified gerbera than in the wild type. The fraction of thermal dissipation （D） was increased under drought stress. However, the fraction of excess energy （E） was not changed during drought stress and recovery.
出处
《园艺学报》
CAS
CSCD
北大核心
2007年第1期157-162,共6页
Acta Horticulturae Sinica
关键词
非洲菊
干旱胁迫
光合作用
叶绿素荧光
Gerbera
Drought stress
Chlorophyll fluorescence
Photosynthesis
