Effects of water stress on chlorophyll fluorescence parameters in seedlings of different maize hybrids.

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.