基于根系形态及空间分布的甘蔗磷高效吸收特征分析  

Analysis of Efficient Phosphorus Absorption Characteristic Based on Root Morphology and Spatial Distribution in Sugarcane

作　　者：易科 杨曙[1] 孔吴俊 陈迪文 谢璐 唐新莲[1] 黎晓峰[1] 赵尊康 YI Ke;YANG Shu;KONG Wujun;CHEN Diwen;XIE Lu;TANG Xinlian;LI Xiaofeng;ZHAO Zunkang(College of Agriculture,State Key Laboratory for Conservation and Utilization of Subtropical Agrobioresources,Guangxi Key Laboratory for Sugarcane Biology,Guangxi University,Nanning 530004,China;Henry Fok School of Biology and Agriculture,Shaoguan University,Shaoguan,Guangdong 512000,China;Agricultural and Rural Bureau of Kecheng District,Quzhou City,Quzhou,Zhejiang 324000,China;Institute of Nanfan Seed Industry,Guangdong Academy of Sciences,Guangzhou 510316,China;College of Land Resources and Environment,Jiangxi Agricultural University,Innovative Integration Center of Industry and Education in Resource Utilization of Agricultural Waste,Prevention and Control of Non-point Pollution of Jiangxi Province,Nanchang 330045,China)

机构地区：[1]广西大学农学院/广西甘蔗生物学重点实验室/亚热带农业生物资源保护与利用国家重点实验室,广西南宁530004 [2]韶关学院英东生物与农业学院,广东韶关512000 [3]衢州市柯城区农业农村局,浙江衢州324000 [4]广东省科学院南繁种业研究所,广东广州510316 [5]江西农业大学国土资源与环境学院/江西省农业废弃物资源化利用与面源污染防控产教融合重点创新中心,江西南昌330045

出　　处：《江西农业大学学报》2022年第6期1362-1372,共11页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金项目(31660592);广西自然科学青年基金项目(2015GXNSFBA139071、2021GXNSFAA075017)。

摘　　要：【目的】以广西为首的亚热带甘蔗主产区由于受到土壤酸化的影响,耕地土壤有效磷普遍缺乏。探究甘蔗根系形态和分布特征的基因型差异及其与磷效率之间的关系,可为从根系构型方面进行甘蔗磷效率的遗传性状改良提供理论基础。【方法】以1个磷高效基因型ROC22(RO)和2个磷低效基因型Co285(CO)、Phil72-445(PH)为材料,设置低磷和正常磷2个处理。通过水培和土培试验比较不同基因型的生长和磷吸收差异;通过水培试验和根系动态观测探究甘蔗根系形态和根系空间分布与磷高效吸收的关系。【结果】水培试验中RO的相对生物量和相对磷积累量分别比CO高54%和131%,比PH高166%和320%,而在土培试验中分别比CO高97%和50%,比PH高232%和96%。低磷处理下,CO和PH的各项根系参数都有所下降,而RO的比根长、比根表面积、比根体积和比根尖数均极显著增加,分别比正常磷高182%、234%、296%和143%。相比正常磷,低磷条件下CO和PH在浅层(0~25 cm)的根长密度分别有少量的增加或减少,浅层根长密度占比较低(42%~44%),而RO在浅层的根长密度增加较多,且浅层根长密度占比较高(51%)。相关性分析结果显示,低磷条件下影响甘蔗生长和磷吸收的关键指标是比根长和浅层根长密度。【结论】磷高效基因型RO通过促进侧根生长,增加单位根系的数量、表面积和体积;调节根系空间分布,增加浅层土壤的根系密度和占比,进而增加根系与土壤磷的接触范围,从表土中吸收更多磷来应对低磷胁迫。[Objective]Due to the influence of soil acidification,the soil available phosphorus(P)in the main sugarcane producing areas is generally deficient in the subtropical zone as Guangxi province.Exploring the genotypic differences in the morphology and distribution characteristics of sugarcane roots and their relationship with phosphorus(P)absorption could provide a theoretical basis for improving the genetic traits of phosphorus efficiency in sugarcane from the aspects of root architecture.[Method]A P-efficient genotype ROC22(RO)and two P-inefficient genotypes Co285(CO)and Phil72-445(PH)were used as plant materials,and the low P(LP)and normal P(NP)were set as the two treatments.The differences of growth and P absorption of different genotypes were compared through hydroponic and soil culture experiments.The relationship between root morphology and spatial distribution with efficient P absorption was explored through hydroponics and root dynamic observation.[Result]The relative biomass and relative P accumulation of RO were 54%and 131%higher than those of CO,and 166%and 320%higher than those of PH under hydroponic condition,while those of RO were 97%and 50%higher than those of CO,and 232%and 96%higher than those of PH under soil culture condition.All root morphology parameters of CO and PH were decreased under the LP treatment,while the specific root length,root surface area,root volume and root tip numbers of RO were increased significantly,which were 182%,234%,296%and 143%higher than those of the NP treatment,respectively.The root length density(RLD)of CO and PH in the shallow layer(0-25 cm)increased or decreased slightly under the LP treatment,and the RLD ratio of CO and PH in the shallow layer were lower(42%-44%),compared with the NP treatment.The RLD of RO in the shallow layer increased,and the RLD ratio of RO in the shallow layer was higher(51%).The results of correlation analysis showed that the key indexes affecting sugarcane growth and P absorption under low phosphorus conditions were specific root length an

关 键 词：甘蔗 低磷胁迫 磷高效吸收 根系形态 根系分布 

分 类 号：S311[农业科学—作物栽培与耕作技术] S566.1[农业科学—农艺学]