绒毛白蜡对NaCl胁迫的生理响应

Physiological Response of Fraxinus velutinato NaCl Stress

以新品系耐盐优株绒毛白蜡（Fraxinus velutina）和普通绒毛白蜡为试材,在盆栽条件下用质量浓度为0、1、2、3、4、5、6、7g·kg-1的NaCl溶液进行胁迫处理,测定了胁迫后根、茎、叶中Na＋、K＋含量以及生物量、光合指标、可溶性糖等生理指标,探讨白蜡在NaCl胁迫下的生理响应。结果表明：所选育的新品系白蜡比普通绒毛白蜡耐盐性更强;耐盐机制以聚盐和增加植株内可溶性糖含量为主。耐盐优株白蜡耐盐阈值为5g·kg-1,较普通白蜡高1g·kg-1,随着进一步的选育,绒毛白蜡可作为环渤海盐碱地区绿化的优良树种。耐盐优株白蜡对Na＋吸收随NaCl浓度增加而增加,在各器官积累量随浓度增加有相应变化,在1~3g·kg-1处理中为根〉茎〉叶,4g·kg-1及以上处理中为叶〉茎〉根。Na＋在耐盐优株白蜡体内总积累量高于普通白蜡,低盐浓度在根部聚集,高盐浓度在叶中聚集,聚盐作用显著。耐盐优株白蜡在盐胁迫条件下,植株内可溶性糖含量显著高于普通白蜡,并随NaCl浓度升高显著增加。

Taking new strain salt tolerance Fraxinus velutinaand normal F.velutinaas experimental materials,pot culture were conducted to investigate the Na＋,K＋,biomass and water content changes of F.velutina,which were irrigated with NaCl stress concentration of 0g·kg-1,1g·kg-1,2g·kg-1,3g·kg-1,4g·kg-1,5g·kg-1,6g·kg-1,7g·kg-1 mass concentration.The results showed that the selected new strain F.velutina＇s salt-tolerance ability was better than the normal F.velutina;the main mechanism of salt tolerance was polysalt and increasing soluble sugar content.The salt tolerance F.velutinathreshold was5g·kg-1,1g·kg-1 higher than ordinary F.velutina.Along with further breeding,F.velutina could be used as a good greening tree species of the Bohai Sea salt-affected area.With salt stress concentration increased,Na＋absorption of salt tolerance F.velutinaincreased,the fundamental order of accumulation in various organs changed with the salt stress concentration.In1-3g·kg-1,the order was root〉stem〉leaf;above 4g·kg-1,the order was leaf〉stem〉root.The total accumulation of Na＋in salt tolerance F.velutina was higher than normal F.velutina,when in low salt stress situation,Na＋accumulate in root,accumulate in leaves in high salt stress situation,polysalt significantly.Under high-salt circumstance,the content of soluble sugar in salt tolerance F.velutinahigher than the normal F.velutina,and increased with the increase of salt stress.