Some Stress On Different Chinese Fir Clones Of Chlorophyll Fluorescence Parameters

Chinese fir(Cunninghamia lanceolata) is one of the most important tree species in southern China, with large distribution range across l7 provinces in subtropical area of China. Chinese fir is often under stress caused by drought, high temperature, nutrition and frost damage in the growth process. After previous years of study, chlorophyll fluorescence kinetics has been widely used in light stress, cold stress, heat stress, freezing stress, air pollution, disease and other stress physiology, so comparative analysis of chlorophyll fluorescence parameters of fir under stress is the effective way of seed selection and mechanism research of adverse physiological and biochemical changes. For this reason, this study selected 7 clones(FS01, FS04, FS07, FS11, FS13, FS16 and FS21) seedlings as experimental material, separately went through drought stress, nutrient stress and CO₂ stress. Based on the good resistance to choose fir seeds, and to discuss the adaptive mechanisms of fir under stress.Drought stress selected PEG6000 simulated drought stress environment; nutrient stress went through prespectively on P stress and N stress; According to the World Health Organization's report on the assessment of CO₂, CO₂ concentration will reach to 800ppm in the next 20 years, and 1200ppm in the next 50 years. Therefore, set on CO₂ concentration was 800ppm, 1200ppm. Determination of chlorophyll fluorescence parameters of the Fo, Fm, Fv, Fv / Fm, Fv / Fo, Fv '/ Fm ', qP and NPQ stress in different periods (prophase 0-5 days , medium 5-10days, late 10-15day) , with different stress concentration..The cluster analysis and multiple comparisons of the data lead to the following results:Under drought stress Chinese fir clone Fv/Fm as stress time increases and decreases and the increasing degree of intimidation, and different drought resistance of Chinese fir clone significant differences. In drought stress, in all kinds of chlorophyll fluorescence parameter index, photochemical efficiency Fv/Fm and are related in various Fv/ Fo index of Chinese fir clone light differentiation degree than other index is high.FS13 photochemical efficiency of Fv/Fm significantly higher than other clones, the optical quenches NPQ also higher than other clones, cluster analysis, and the results showed that all index data in different stress FS13 period are clustering in patience type, the most excellent comprehensive index, it results in the seven FS13 cunninghamia lanceolata clones in each clone has better drought resistance. Nutrition stress in adversity stress of the several important parameters (chlorophyll fluorescence Fv/Fm, Fv/Fo, NPQ) are compare and phosphorus stress with the chlorophyll fluorescence calculations generally higher than nitrogen stress intimidation processing, on nitrogen stress, clones coerced processing chlorophyll fluorescence dynamic affected considerably. For nitrogen stress intimidated by chlorophyll fluorescence parameters, it is concluded that the clustering analysis, FS07 sensitive FS01 nitrogen stress resistance is higher. Through phosphorus stress of chlorophyll fluorescence parameters are clustering analysis, can infer that FS16 is better than other fir clone of the resistance, and FS07 in phosphorus stress sensitive than others.Comparative analysis of Chinese fir in CO₂ intimidation chlorophyll fluorescence parameter index of the clone, found in CO₂ intimidation of Chinese fir clones of Fv/xsl-fo most sensitive, with time and intensity increased CO₂ stress is rising trend, and other chlorophyll fluorescence index data changes are not obvious, also did not reach the level of Chinese fir physiological health hazards, can infer that even in the next 50 years 1200ppm elevated CO₂ concentrations, nor to these seven fir clones of chlorophyll fluorescence dynamic index cause too big effect.