不同种源杉木幼苗对干旱胁迫的抗性差异

Resistance Response of Cunninghamia lanceolata Seedlings from Different Provenances to Drought Stress

本试验以北亚热带安徽休宁、中亚热带江西安福和湖南会同、南亚热带广西融水和广东信宜5个不同种源杉木幼苗为试验材料,采用水培法,以PEG 6000模拟干旱胁迫,分析了不同种源杉木幼苗对干旱胁迫的生长生理响应。结果表明:在0%~20%PEG 6000处理下,随着PEG浓度增加,苗木高径增量逐渐减小、叶片水分亏缺率增大,SOD、POD、CAT活性及可溶性糖、可溶性蛋白、游离脯氨酸含量呈先上升后下降的趋势。除苗高外,种源对干旱胁迫下杉木幼苗生长生理影响显著,整体上均以安徽休宁表现最佳。以地径增量、叶片相对水分亏缺率及SOD、POD、CAT活性与可溶性糖、可溶性蛋白、游离脯氨酸含量8个指标作为评价指数,通过主成分分析综合评价,供试5个种源抗旱能力大小为:安徽休宁>湖南会同>江西安福>广西融水>广东信宜。研究认为,杉木干旱敏感性强,种源间抗旱能力差异较大,以北亚热带种源抗旱性最强,其次为中亚热带种源,而南亚热带种源抗旱性最弱。

In this experiment,Cunninghamia lanceolata seedlings from five different provenances in northern subtropical Anhui Xiuning,central subtropical Jiangxi Anfu and Hunan Huitong,southern subtropical Guangxi Rongshui and Guangdong Xinyi were used as experimental materials.The growth and physiological responses of C.lanceolata seedlings from different provenances to drought stress were analyzed by hydroponic method with PEG 6000 simulated drought stress.The results showed that with the increase of PEG 6000 concentration from 0%~20%,the height and diameter increment of seedlings decreased gradually,and the water deficit rate of leaves increased.The activities of SOD,POD and CAT and the contents of soluble sugar,soluble protein and free proline increased first and then decreased.In addition to seedling height,the provenance had a significant effect on the growth physiology of C.lanceolata seedlings under drought stress,and Anhui Xiuning performed best overall.The eight indexes of ground diameter increment,leaf relative water deficit rate,SOD,POD,CAT activity and soluble sugar,soluble protein and free proline content were used as evaluation indexes.Through the comprehensive evaluation of principal component analysis,the drought resistance of the five provenances was:Anhui Xiuning>Hunan Huitong>Jiangxi Anfu>Guangxi Rongshui>Guangdong Xinyi.The results showed that C.lanceolata was highly sensitive to drought,and there were great differences in drought resistance among provenances.The drought resistance of northern subtropical provenances was the strongest,followed by central subtropical provenances,and the drought resistance of southern subtropical provenances was the weakest.