镁营养对大豆苗期生长及根系形态构型的影响  

Effect of magnesium nutrition on growth and root system architecture traits of soybean seedlings

作　　者：刘昭阳 李书悦 毛婧莹 燕涵 梁翠月 陆星[1] 田江[1] LIU Zhaoyang;LI Shuyue;MAO Jingying;YAN Han;LIANG Cuiyue;LU Xing;TIAN Jiang(College of Natural Resources and Environment/Root Biology Center,South China Agricultural University,Guangzhou 510642,China)

机构地区：[1]华南农业大学资源环境学院/根系生物学研究中心,广东广州510642

出　　处：《华南农业大学学报》2024年第3期321-328,共8页Journal of South China Agricultural University

基　　金：国家自然科学基金(32172659,31601830)。

摘　　要：【目的】镁是植物生长必需的矿质营养元素,研究大豆在不同镁浓度下的苗期生长情况及根系三维构型的动态变化。【方法】以磷高效大豆品种‘粤春03-3’为研究对象,营养液培养,设置镁浓度为0、262.5、525.0、787.5和1050.0μmol/L,分析苗期大豆的生长发育状况。在此基础上,利用根系三维定量系统对正常镁处理(525.0μmol/L,对照)及缺镁处理(0μmol/L)的大豆根系三维构型进行动态定量化分析。【结果】与525.0μmol/L对照相比,0μmol/L缺镁处理大豆的地上部干质量、根冠比、老叶SPAD、总根长和根系总表面积分别减少89.04%、48.67%、51.42%、93.36%和94.31%。而其他3个镁浓度条件下,大豆生长与对照差异较小。根系三维构型研究发现,与对照相比,随着处理时间的延长,缺镁处理显著降低大豆根系的总根长、总根表面积、根重心、根尖数、凸包体积、最大根宽、最小根宽、最大根深、最大根宽/最大根深,对根系充实度、分根繁茂度和根体积分布的影响较小。【结论】本研究明确了大豆对外界镁有效性的适应范围较广,借助优化的根系三维重建技术,阐明缺镁显著降低大豆根系的总根长、根尖数、根重心、最大根宽等,但对根系充实度、分根繁茂度、根体积分布动态变化规律的影响较小。研究结果对大豆镁肥的合理施用和镁营养诊断有一定的指导意义。【Objective】Magnesium(Mg)is an essential mineral nutrient for plant growth.This study was aimed to investigate the growth and dynamic changes in three-dimensional root system architecture traits of soybean seedlings under different Mg concentrations.【Method】The phosphorus-efficient soybean genotype‘Yuechun 03-3’was selected as the research object,and Mg concentrations were set in hydroponics as 0,262.5,525.0,787.5 and 1050.0μmol/L to explore the effect of Mg nutrition on the growth and development of soybean seedlings.Furthermore,the optimized three-dimensional root quantification system was used to analyze the dynamic quantitative changes in the root system architecture traits of soybeans under control Mg treatment(525.0μmol/L)and Mg deficiency treatment(0μmol/L).【Result】Compared with the control of 525.0μmol/L Mg,the soybean shoot dry mass,root-to-shoot ratio,SPAD of old leaves,total root length,and total root surface area under the 0μmol/L Mg deficiency treatment decreased by 89.04%,48.67%,51.42%,93.36%and 94.31%respectively.Under other three Mg concentration conditions,the growth of soybeans showed relatively small differences compared with the control.The results of three-dimensional root system quantification found that compared with the control Mg treatment,Mg deficiency treatment significantly reduced the total root length,total root surface area,root centroid,number of root tips,convex hull volume,maximum root width,minimum root width,maximum root depth and maximum width/maximum depth of soybean roots with the extension of treatment time.However,it affected root solidity,bushiness and root volume distribution feebly.【Conclusion】This study elucidates the wide adaptability range of soybeans to external Mg availability.By utilizing optimized three-dimensional root reconstruction techniques,it is found that Mg deficiency significantly reduces the total root length,number of root tips,root centroid and maximum root width of soybeans,while it does not significantly affect the dynamic ch

关 键 词：大豆 镁 苗期 生长 根系三维定量 根系构型 

分 类 号：S511[农业科学—作物学] S502