【摘要】 以玉米品种京科25和吉单261为试验材料,研究苗期叶片叶绿素荧光参数。结果表明,水分胁迫对叶绿素荧光参数的影响非常显著,玉米叶片的基础荧光增大,而可变荧光、PSⅡ光化学效率及PsⅡ潜在活性显著降低;在水分胁迫条件下,吉单261PSⅡ原初光化学效率(Fv/Fm)、光化学淬灭系数(qP)、实际光化学效率(ΦPSⅡ)及电子传递速率(ETR)的下降较少,非光化学淬灭系数(qN)增加较少。表明吉单261在水分胁迫条件下,光合机构受破坏较轻,其吸收的光能可以较多的用于光化学转化,通过热耗散的能量较少。更多还原

【Abstract】 Using sweet maize Jingke25 and Jidan261 as materials. The experiment results showed that fluorescence parameters of the maize seedling were significantly affected by the water stresses. The basis fluorescence (Fo) of the maize leaves increased, and the variable fluorescence (Fv) and photochemical efficiency (Fv/Fm) and the potential activities of PSⅡ(Fv/Fo) decreased markedly. Under water stressed, the decrement of PSⅡprimary photochemical efficiency(Fv/Fm), photochemical quenching coefficient(qP), the actual photochemical efficiency of ΦPSⅡand electron transport rate were less; increment of non- photochemical quenching coefficient (qN) were less in Jidan261. The above results suggested that damage of photosynthetic apparatus were lighter; more light energy absorbed by Jidan261 was converted into chemical energy and less light energy was dissipated through thermal energy.更多还原