低温对三种暖季型草坪草叶绿素荧光特性的影响

Effects of Chilling on Chlorophyll Fluorescence Characteristics in Three Warm-season Turfgrasses

研究了低温对假俭草、狼尾草、中华结缕草三种暖季型草坪草叶绿素荧光特性的影响。结果表明:低温引起假俭草、狼尾草、中华结缕草三种暖季型草坪草的初始荧光F0上升,PSⅡ最大光化学效率(Fv/Fm)、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)、PSII电子传递量子产率(ФPSⅡ)、光合电子传递速率(ETR)、非光化学猝灭系数(qN)下降,致使光合速率(Pn)急剧下降。至低温处理后72h,三种暖季型草坪草中Fv/Fm、Fv′/Fm′、qP、ФPSⅡ、qN的值结缕草>狼尾草>假俭草,F0则出现相反的结果,Pn值结缕草>狼尾草>假俭草。研究还表明,利用非损伤的叶绿素荧光技术可快速地筛选不同基因型暖季型草坪草的抗寒能力。

Three warm-season turfgrasses, Eremochloa ophiuroides Hack, Pennisetum alopecuroides Spreng, Zoysia sinica Hance, were used to study the effects of chilling stress on chlorophyll fluorescence characteristics. The results showed that maximal photochemical efficiency of PSⅡ （Fv/Fm）, efficiency of excitation energy captured by open PSⅡ reaction centers （Fv′/Fm′）, photochemical quenching （qP）, quantum yield of PSⅡ electron transport （φPSⅡ）, electron transport rate of PSⅡ （ETR）, non-photochemical quenching （qN） in leaves were reduced while minimal fluorescence （F0） was risen after chilling, which made net photosynthetic rate dropped sharply. After 72 h chilling stress, the orders of Fv/Fm,Fv′/Fm′, qP,φPSⅡ, qN in three warm-season turfgrasses were Zoysia sinica Hance 2〉 Penniseturn alopecuroides Spreng 2〉 Eremochloa ophiuroides Hack and the orders of F0 in them were just opposite to those of Fv/Fm,Fv′/Fm′,qP,φPSⅡ,qN, the net photosynthetic rate （Pn） was Zoysia sinica Hance 2〉 Pennisetum alopecuroides Spreng 2〉 Erernochloa ophiuroides Hack . Those results showed the potential for using the fast and noninvasive techniques-chlorophyll fluorescence to screen for different chilling resisrance warmseason turfgrasses genotypes.