铵态氮素促进甘薯块根形成的解剖特征及其IbEXP1基因的表达  

Anatomy characteristics and IbEXP1 gene expression of tuberization under ammonia nitrogen treatment in sweet potato

作　　者：王翠娟 柴沙沙[2] 史春余[3] 朱红 谭中鹏 季杰 任国博 WANG Cui-Juan;CHAI Sha-Sha;SHI Chun-Yu;ZHU Hong;TAN Zhong-Peng;JI Jie;REN Guo-Bo(Institute of Sweet Potato,Yantai Academy of Agricultural Sciences,Yantai 265500,Shandong,China;Institute of Food Crops,Hubei Academy of Agricultural Sciences/Hubei Engineering and Technology Research Center of Sweetpotato/Hubei Key Laboratory of Food Crop Germplasms and Genetic Improvement,Wuhan 430064,Hubei,China;Resources of Horticulture Science and Engineering,Shandong Agricultural University/State Key Laboratory of Crop Biology,Tai’an 271018,Shandong,China;Crop Protection Institute,Shandong Agricultural University,Tai’an 271018,Shandong,China;Luxi Chemical Group Co.Ltd.,Liaocheng 252000,Shandong,China)

机构地区：[1]山东省烟台市农业科学研究院,山东烟台265500 [2]湖北省农业科学院粮食作物研究所/湖北省甘薯工程技术研究中心/粮食作物种质创新与遗传改良湖北省重点实验室,湖北武汉430064 [3]山东农业大学农学院/作物生物学国家重点实验室,山东泰安271018 [4]山东农业大学植物保护学院,山东泰安271018 [5]鲁西化工有限公司,山东聊城252000

出　　处：《作物学报》2021年第2期305-319,共15页Acta Agronomica Sinica

基　　金：山东省薯类产业创新团队首席专家项目(SDAIT-16-01)资助。

摘　　要：探讨铵态氮素对甘薯块根形成的调控效应及其作用机制,本研究利用单株结薯数差异显著的甘薯品种商薯19(S19)和济徐23(J23)为材料,于2014-2015年进行大田试验和盆栽辅助试验,设置60 kg hm^–2低氮(LN60)和180 kg hm^–2高氮(HN180)2个氮素水平,酰胺态(XN)和铵态(AN)2种氮素形态,进行甘薯幼根向块根分化关键时期的发育解剖观察和IbEXP1基因的表达分析。结果表明,单株有效结薯数较高的商薯19块根产量显著高于济徐23,生长前期甘薯块根的分化建成相较于块根的膨大生长更利于最终块根产量的形成。同时,2个甘薯品种60 kg hm^–2铵态氮素处理在茎叶封垄期建成更多根径介于0.5~5.0 cm的薯块,显著提高了收获期的单株有效薯块数目,块根产量最高。其中,60 kg hm^–2铵态氮素处理2个品种甘薯幼根在前形成层时期原生木质部束的导管数目及中柱薄壁组织木质化薄壁细胞数目最多;初生形成层发育时期IbEXP1基因高水平表达,幼根直径、中柱直径大,原生、次生木质部束数目多;次生形成层活动初期IbEXP1基因的相对表达和中柱薄壁细胞的木质化程度介于不施氮和高氮素处理之间,但幼根直径、中柱直径和中柱占横截面比均显著最高,在块根分化建成中建立了中柱薄壁细胞木质化活动和分裂活动的平衡。This study chose Shangshu 19(S19)and Jixu 23(J23)categorized by valid tuber root number per plant as analyzing varieties and arranged treatment combinations consisted of two nitrogen forms ammonium nitrogen(AN)and amide nitrogen(XN)integrated with two nitrogen rates 60 kg hm^-2(LN60)and 180 kg hm^-2(HN180),using field and pot trial assays,plus a check treatment received no nitrogen supply in order to make research on the anatomical observation on sweet potato tuber root differentiation and expression characteristics of IbEXP1 gene associated with tuber root formation in ammonia nitrogen in 2014 and 2015.Our results showed that the storage root yield of Shangshu 19 associated with more valid tuber root number per plant was signifi cantly higher than Jixu 23 at harvest stage,which was significant difference compared with each other.In addition,nitrogen levels and nitrogen forms had significant interaction effects.The 60 kg hm^-2 ammonium nitrogen treatment in two sweet potato genotypes achieved the highest final storage root yield in field experiment and showed higher valid tuber root number per plant,which attributed to the younger tubers whose root diameter between 0.5 cm and 5.0 cm during the canopy closure period.It had been observed that 60 kg hm^-2 ammonium nitrogen treatment possessed the most vessels in the primary xylem bundle and the lignified parenchyma cells of the stele tissues in the pre-cambial period,followed with possessing high level expression of IbEXP1 gene,the biggest root diameter and stele diameter and the most number of primary and secondary xylem bundles in the course of primary cambium growth.As the vascular cambium was initiated,relative expression of IbEXP1 gene at 60 kg hm^-2 ammonium nitrogen treatment and the degree of parenchyma cells lignification were intermediate between no nitrogen application and high nitrogen treatments,however,the diameter of root and stele and the ratio of them were highest,which achieved the perfect harmony in lignification and division of parenchyma cells i

关 键 词：甘薯 铵态氮素 块根分化建成 解剖观察 IbEXP1基因 

分 类 号：S531[农业科学—作物学]