水分胁迫对马铃薯出苗期根系生理特性及内源激素IAA、ABA含量的影响

Effects of water stress on physiological characteristics and endogenous hormone IAA and ABA contents in seedling root of potato

采用盆栽试验,以马铃薯克新1号为供试材料,设置中度水分亏缺(T1)、重度水分亏缺(T2)、正常供水(CK)和水涝胁迫(T3)4个水分处理,研究了水分胁迫对马铃薯出苗期根系生理特性和内源激素含量的影响,探讨了土壤水分胁迫对马铃薯出苗期根系生长发育及其生理过程的影响机制.结果表明:(1)随着水分亏缺程度的加剧和时间的延长,根系活力、MDA含量、脯氨酸含量、可溶性蛋白含量、SOD活性、CAT活性和POD活性升高,在水分胁迫初期,根系中CAT、POD活性较SOD响应更敏感,表明胁迫前期主要依赖CAT、POD,后期通过CAT、POD和SOD共同作用来降低氧化伤害;水涝胁迫下,根系活力一直低于正常供水,MDA含量不断升高,可溶性蛋白含量、脯氨酸含量、SOD活性、CAT活性和POD活性有先升高后降低的趋势,但不敏感;水分胁迫下,IAA含量降低,ABA含量升高,IAA/ABA比值降低,影响根系正常发育,影响吸收水分和养分、影响出苗.(2)IAA含量和可溶性蛋白含量呈极显著负相关,ABA含量与可溶性蛋白含量呈显著正相关,与CAT活性呈极显著正相关.研究表明,马铃薯出苗期根系通过对渗透物质、保护酶和内源激素的调节来维持自身的正常生理代谢功能,抵抗一定的水分亏缺,但亏缺加剧时,将严重影响马铃薯出苗.

To study the effects of physiological characteristics and endogenous hormone under water stress in seedling roots of potato,potted Kexin 1 seedlings under four different soil content levels：moderate water stress（T1）,severe water stress（T2）,optimal water content（CK）and waterlogged stress（T3）,which were controlled by weighing the soil and pots.The results showed that：（1）With the increase of stress level and along with the period of water stress continued,the potato root activity,MDA content,proline content,soluble protein content,SOD activity,CAT activity,POD activity were increased.In preliminary stress,CAT and POD were more sensitive than SOD in root,root in water stress early mainly depends on CAT and POD to reduce oxidation damage,and then through the CAT,POD and SOD common action to reduce the oxidation damage;In waterlogged stress,root activity was lower than CK,MDA content was increased,proline content,soluble protein content,SOD activity,CAT activity,POD activity were increased and then decreased,not sensitive;In water stress,IAA content was decreased,ABA content was increased,IAA/ABA was decreased,affecting the normal development of roots,affecting the absorption of water and nutrients,affecting the emergence.（2）IAA contents were negatively related with soluble protein at 0.01 level,and ABA contents were positively related with soluble protein at 0.05 level,and with CAT at 0.01 level.So can conclude that the growth of potato roots were negatively influenced by different degree of water stress,but the osmotic adjustment substance,the protective enzyme system and endogenous hormone could adjust themselves to avoid water stress harms,but the stress intensify,will seriously affect the emergence of potatoes.