Study On Drought Resistance Evaluation Of Pinus Bungeana Germplasm Resource

Pinus bungeana is the only three-needle pine of East Asia, and is a native plant species in China. It is widely transplanted in North China.Pinus bungeana, a rare species with its advantage of beautiful tree form, strong adaptability, good resistance, becomes the preferred species of forestry production and landscaping. This paper took ten provenances of Pinus bungeana for the research object, evaluating the growth characters. Determine the water content, chlorophyll content, soluble sugar content, soluble protein content, proline content, MDA content and SOD activity under natural drought condition,using the membership function analysis method and clustering analysis method to evaluate drought resistance strength of ten provenance of Pinus bungeana comprehensively, and using the grey correlation analysis method to analyze various indicators of correlation. The main results were as follows:1. The measurement results of seedling height, ground diameter had significant differences in different provenances of Pinus bungeana, from which the provenance of Tianshui, Liangdang, Luonan growed best.2. The analysis of physiological indexes of Pinus bungeana from ten provenances showed that there were remarkable differences of indicators among different provenances. The result of correlation analysis based on 7 physiological biochemistry indexes showed that: water content was significantly negatively correlated with chlorophyll content and MDA content, soluble sugar content was significantly positively correlated with proline content, soluble protein content was extreme significantly positively correlated with MDA content.3. By the membership function analysis method, the results showed that the drought resistance of ten provenances of Pinus bungeana from strongest to the weakest were as follows : Longxian > Lantian > Zhengzhou > Linfen > Xiaoyi >Liangdang>Beijing>Jing Tusi>Tianshui>Luonan.4. The ten provenances of Pinus bungeana were divided into four groups by clustering analysis method: Lantian and Longxian were in group one, belonging to the highly drought resistant type; Zhengzhou, Linfen were in group two, belonging to the stronger drought resistant type; Liangdang, Tianshui, Beijing, Jing Tusi, Xiaoyi were in group three, belonging to the medium drought resistant type; Luonan was in group four only, belonging to the weak drought resistant type.5. Use the grey correlation analysis method to calculate the correlation of each index, and the correlation order was: SOD activity>soluble protein content>water content>chlorophyll content>MDA content>proline content>soluble sugar content. The result showed that SOD activity, soluble protein content, water content, chlorophyll content, MDA content can be used as important indexes of drought resistance identification.