外源生长素调控甘薯根系响应低钾胁迫的效应  

Effects of exogenous auxin on root response to low potassium stress in sweetpotato

作　　者：刘明 靳容[1] 赵鹏 张强强 朱晓亚 王静[1] 于永超 唐忠厚[1] Liu Ming;Jin Rong;Zhao Peng;Zhang Qiangqiang;Zhu Xiaoya;Wang Jing;Yu Yongchao;Tang Zhonghou(Xuzhou Institute of Agricultural Sciences in Xuhuai District of Jiangsu/Key Laboratory of Sweetpotato Biology&Genetic Breeding,Ministry of Agriculture&Rural Affairs,Xuzhou 221121,Jiangsu,China)

机构地区：[1]江苏徐淮地区徐州农业科学研究所/农业农村部甘薯生物学与遗传育种重点实验室,江苏徐州221121

出　　处：《江苏师范大学学报（自然科学版）》2023年第2期29-34,共6页Journal of Jiangsu Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(32001482);财政部和农业农村部:国家现代农业产业技术体系资助项目(CARS-10)。

摘　　要：利用外源方法调控根系生长是提高植物对低钾耐受性的重要策略.采用水培方式,研究低钾胁迫下喷施生长素(IAA)对苗期甘薯钾吸收、根系特征和内源IAA的影响.结果表明:1)低钾胁迫显著降低了甘薯幼苗的生物量和钾积累量,减少了根系的总根长和投影面积,与对照相比,徐薯32(耐低钾型)这4个指标的下降率比宁紫薯1号(低钾敏感型)更低.2)外源IAA通过增加侧根的长度和比例,提高根系总长度和投影面积,并增加生物量和钾积累量,从而减轻低钾的抑制作用.这一过程与外源IAA提高了叶片和根中内源IAA含量有关.3)外源IAA对缓解徐薯32低钾胁迫伤害的效应优于宁紫薯1号,是因为徐薯32合成更多的内源IAA,促发更多的侧根,以提高对钾的吸收.综上,外源IAA通过调节内源IAA的合成,提高甘薯根系对低钾胁迫的适应性,一定程度上提高了甘薯的耐低钾能力.Exogenous methods to regulate root growth are important strategy to improve plant tolerance to low potassium(K+).The effects of exogenous auxin(IAA)on K+uptake,root characteristics,and endogenous IAA of sweetpotato seedlings under low K+stress were studied by hydroponics.The results showed that:1)Low K+stress significantly decreased the biomass and K+accumulation of sweetpotato seedlings,and decreased the roots total length and projected area.Compared to the control group,the decrease rates of these four indicators of Xushu 32(low K+tolerant type)were lower than that of Ningzishu1(low K+sensitive type).2)Exogenous IAA increased the roots total length and projected area,and increased the biomass and K+accumulation by increasing the length and proportion of lateral roots,thus alleviating the inhibition effect of low K+.This process was related to the increase of endogenous IAA content in leaves and roots by exogenous IAA.3)The effect of exogenous IAA on alleviating the damage caused by low K+stress in Xushu 32 was better than that in Ningzishu 1.This is because Xushu 32 synthesized more endogenous IAA,which promoted the production of more lateral roots and improved the absorption of K+.In summary,exogenous IAA improved the adaptability of sweetpotato roots to low K+stress by regulating the synthesis of endogenous IAA,and improved the low K+tolerance of sweetpotato to a certain extent.

关 键 词：甘薯 生长素 耐低钾能力 根系形态 外源调控 

分 类 号：S311[农业科学—作物栽培与耕作技术] S531[农业科学—农艺学]