不同磷形态对两种磷效率小麦根系指标与根际特征差异的影响  

Response of Rhizosphere Characteristics of Two different P-efficiency Wheat Genotypes(Tritium aestivum L.) to the Inorganic and Organic Phosphorus Sources

作　　者：展晓莹[1] 候焱焱 张淑香[1] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所,北京100081 [2]云南农业大学资源与环境学院,云南昆明650201

出　　处：《核农学报》2013年第7期1012-1019,共8页Journal of Nuclear Agricultural Sciences

基　　金：公益性行业(农业)科研专项(201203030)

摘　　要：磷高效基因型小麦的筛选,对于高效合理地利用生物有效性低的土壤磷源有着极其重要的意义。本文以典型的磷高效型小麦小偃54和磷低效型小麦京411为研究对象,采用石英砂砾培养的方式种植40d,通过测定小麦的生物量、含磷量、根系形态、根系酸化能力和酸性磷酸酶活性,探索了两种磷效率小麦根系形态和生理特征对两种不同无机磷源磷酸铁(FePO4)和有机磷源植酸钠(Na-Phytate)的响应。结果表明:施用FePO4时,与京411相比磷高效型小麦小偃54表现出根长显著伸长、pH值显著降低和根系吸收质子显著减少的适应性反应,根系生物量和根冠比显著低于京411,小偃54的根系生物量仅为京411的83%,并且在此施肥条件下,两种小麦的地上生物量低于无磷处理。小偃54的磷高效性在施用Na-Phytate时可以得到体现。施用Na-Phytate会导致小偃54的根长伸长、根尖数增加与单位根鲜重酸性磷酸酶的分泌量增加。两种小麦苗龄为40d时对Na-Phytate的利用效率显著高于FePO4,其表现为小偃54在Na-Phytate处理下的地上生物量和含磷量为FePO4处理的148%和336%,京411的地上生物量和含磷量为FePO4处理的146%和391%。FePO4与Na-Phytate混施时两种小麦的生物量和含磷量并未比单施Na-Phytate高,由上述结果可知两种小麦对介质中不同磷源的利用机制不同。To explore the genetic resources of crops is a feasible way to utilize the less bioavailable phosphorus（P） in soils,and to cope with shortage of rock phosphate.A sandy culture experiment with two treatments of phosphorus（P） fertilizers as organic（Na-Phytate）,inorganic（FePO4） and their mixture,was conducted to study the difference between two wheat genotypes（cv.Xiaoyan54 and Jing411） in their root morphological,proton,acid phosphatase secretion and the relationship to biomass and P accumulation.After applied with FePO4,aboveground biomass of thetwo wheat varieties were lower than the non-phosphorus treatment.The P-efficient wheat Xiaoyan54 expressed responsed with elongation of root length and reduction of rhizosphere pH,protons flow,root biomass and root-cap ratio compared with P-inefficient Jing411.When applied with FePO4,the root biomass of Xiaoyan54 only accounts for 83% of Jing411.Xiaoyan54 could accumulate more P than Jing411 under the treatment of Na-Phytate（Na-Phytate） through extension of root length,and increasing of root tip numbers and acid phosphatase secretion of per weigh root.The two genotypes of wheat had higher P efficiency at the seedling stage（40 days） under Na-Phytate treatments rather than FePO4.The data showed that biomass and P accumulation of Xiaoyan54 on Na-Phytate accounts for 148% and 336% under FePO4 treatment,and the biomass and P accumulation of Jing411 treated with Na-Phytate accounts for 146% and 391% under FePO4treatment.There were no significant changes of biomass and P accumulation between the combined application of Na-Phytate with FePO4and the single application of Na-Phytate.All the findings suggested that mechanism of P utilization differed between the two wheat genotypes.

关 键 词：无机磷 有机磷 小麦基因型 根系形态 根际特性 

分 类 号：S512.1[农业科学—作物学]