Contrast Study On Growth And Physiological Characteristics Of Different Catalpa Bungcei Cultivars In Hill Upland

In upland of Xiashu forestry centre in Zhenjiang city, 2-year-old seedlings of 7 Catalpa bungei cultivars were studied in height growth, diameter growth, biomass per plant, leaf and branch characteristics, transpiration rate, stoma tic conductance, photosynthesis rate, intercellular CO₂ concentration, chlorophyll fluorescence parameters and so on. Correlative analysis of growth and physiological characteristics were also did. Furthermore, 14 growth and physiological characteristics were chosen to made comprehensive evaluations by method of Q-mode system cluster analysis. The main conclusions can be drawn as follows:1. Different Catalpa bungei cultivars had significant variance in height, diameter, total biomass per plant, leaf biomass per plant, stem biomass per plant, root biomass per plant, had no significant variance in leaf biomass/total biomass, stem biomass/total biomass, root biomass/stem biomass.2. Different Catalpa bungei cultivars had significant variance in leaf lenght, had most significant variance in leaf width, length to width kf leaf, had significant variance in leaf numbers per plant, had no significant variance in one leaf weight and branch numbers per plant.3. Different Catalpa bungei cultivars had no significant variance in transpiration rate, stoma tic conductance, intercellular CO2 concentration, had significant variance in photosynthesis rate. Different Catalpa bungei cultivars had no significant variance in q_p, NPQ,ΦPS II and Fv/Fm.4.Correlative analysis showed that diameter had conspicuous positive correlation with height growth rate and net photosynthesis rate, had most significant positive correlation with diameter growth rate, length to width kf leaf, transpiration rate; leaf length had conspicuous positive correlation with leaf width and diameter growth rate; leaf width had negative correlation with transpiration rate, q_p, and net photosynthesis rate; diameter growth rate had conspicuous positive correlation with length to width kf leaf, transpiration rate, had most significant positive correlation with net photosynthesis rate; q_p had most significant positive correlation with NPQ;ΦPS II had most significant negative correlation with q_p and NPQ, had significant positive correlation with Fv/Fm. Additionaly, correlative analysis also showed that branch numbers per plant had conspicuous positive correlation with seedling height; biomass per plant had significant positive correlation with height growth rate, diameter growth rate and Fv/Fm.5. Q-mode system cluster analysis showed that 7 Catalpa bungei cultivars could been clustered to 2-4 groups. Number 4 cultivar NanYang Qiu similarly could been clustered to 1 type, the seedings of it had wider diameter, faster growth rate, longer leaf, high length to width ratio of leaf, had maximal transpiration rate, net photosynthesis rate and Fv/Fm, it can be valuable wood-utilization breeding material in the future.