The Change Of Ultra Weak Luminescence During The Drought Stress And Its Excitation Mechanism In Grape

Cabernet sauvignon and merlot were used as materials and water control way were adopted to drought stress.To explore the rationlation between the change of the Ultra weak luminescence and photosynthesis,active oxygen and energy lever during the drought stress by studying the change of the ultra weak luminescence,growth vigor,photosynthesis,active oxygen system and energy level in grape leaves.The main results were as follows:1.During the drought stress,the soil water content,the leaf relative water content,the free water content,free water/bound water and root activity of the two kinds of grape gradually decreased,the bound water content gradually increased,that the growth vigor of the grape deceased.UWL intensity were falling.lt descripted that UWL intensity decreased with the deepening of drought stress.The UWL could reflect the extent of drought stress.2.During the drought stress,the reactive oxygen species of grape leaves were cumulative,UWL intensity showed a trend of gradual decreasing,it showed that the accumulation of reactive oxygen species did not cause the increasing of UWL intensity,the accumulation of reactive oxygen species are not the direct source of the UWL.3.During the drought stress,photosynthetic indexes of grape leaves:net photosynthetic rate,stomatal conductance and transpiration rate showed a trend of falling with the deepening of stress,the internal CO2 increased gradually.Fluorescence parameters Fv/Fm,Yield,qP gradually decreased,qN gradually increased;Photosynthetic pigment content of chlorophyll a and chlorophyll b were declining,UWL intensity decreased,seen that during the drought stress the UWL intensity reduced along with the weakening of photosynthesis,photosynthesis has a relationship with UWL.4.During the drought stress,the ATP content,energy charge showed a trend of gradual decreasing,the ADP content,AMP content gradually increased,UWL intensity overall decreased,seen that the UWL intensity declined with the decreasing of energy level,the energy could be used as one of the main source of UWL.