玉米根系对局部氮磷供应响应的基因型差异

发布时间：2019-05-27 11:01

【摘要】：【目的】土壤养分具有异质性,揭示不同基因型玉米根系对于养分异质性的响应规律,对提高不同玉米品种氮、磷利用效率具有重要意义。【方法】本试验在水培条件下,利用分根系统研究3个玉米杂交种苗期根系对氮、磷两种养分局部供应响应的基因型差异。【结果】根系对局部供氮的响应存在基因型差异,浚单20和中农玉99侧根生长对局部供氮的响应较敏感,显著提高了局部供氮(+N)一侧的侧根长,增幅达到79%、50%,而NE15无显著响应;浚单20和中农玉99主要提高了+N一侧直径大于0.12 mm的侧根长度。根系生长对于局部供磷(+P)的反应同样存在基因型差异,NE15显著提高+P一侧根系生物量和轴根长,增幅达到38%和24%,中农玉99显著提高+P一侧的侧根长达到35%;在+P侧,浚单20主要增加了直径大于0.12 mm的侧根长度,NE15主要增加直径介于0.12~0.24 mm的侧根长度,而中农玉99主要增加直径小于0.12 mm的极细侧根长度。局部供氮对3个品种侧根生长的促进作用强于局部供磷,而对缺氮一侧根系生长的抑制作用均大于缺磷一侧。不同玉米基因型苗期根系生物量、侧根长(尤其是直径0.12 mm的侧根)对于局部供应氮、磷存在显著的互作效应,局部供氮对浚单20的侧根生长(尤其是直径0.12 mm的侧根)的促进作用显著高于局部供磷,而NE15的根系生长(尤其是根系生物量)对局部供磷的响应强度大于局部供氮。【结论】对于不同养分特性的玉米杂交种,苗期根系对局部供应不同种类养分的响应存在显著的基因型差异,在生产中可以针对品种特性采取不同的施肥措施,以便发挥其生物学潜力。
[Abstract]:[objective] soil nutrients are heterogeneous, and the response of different genotypes of maize roots to nutrient heterogeneity is revealed, which is of great significance to improve the utilization efficiency of nitrogen and phosphorus in different corn varieties. [methods] under the condition of hydroponic culture, The genotypic differences of root responses to nitrogen and phosphorus in seedling stage of three maize hybrids were studied by root division system. [results] there were genotypic differences in the responses of roots to local nitrogen supply. The lateral root growth of Jundan 20 and Zhongnongyu 99 was sensitive to local nitrogen supply, which significantly increased the lateral root length of local nitrogen supply (N) by 79% and 50%, while NE15 had no significant response. Jundan 20 and Zhongnongyu 99 mainly increased the lateral root length of N side with diameter greater than 0. 12 mm. There were also genotypic differences in the response of root growth to local phosphorus supply (P). NE15 significantly increased the root biomass and axial root length on the P side by 38% and 24%, and Zhongnongyu 99 significantly increased the lateral root length on the P side by 35%. On the P side, Jundan 20 mainly increased the lateral root length with diameter greater than 0.12 mm, NE15 mainly increased the lateral root length with diameter between 0.12 and 0.24 mm, while Zhongnongyu 99 mainly increased the very fine lateral root length with diameter less than 0.12 mm. The promoting effect of local nitrogen supply on lateral root growth of three varieties was stronger than that of local phosphorus supply, but the inhibitory effect on root growth on nitrogen deficiency side was greater than that on phosphorus deficiency side. The root biomass and lateral root length (especially the lateral root with diameter of 0.12 mm) had significant interaction effects on local nitrogen and phosphorus supply at seedling stage. The effect of local nitrogen supply on the lateral root growth of Jundan 20 (especially the lateral root with diameter of 0.12 mm) was significantly higher than that of local phosphorus supply. The response intensity of root growth (especially root biomass) of NE15 to local phosphorus supply was higher than that of local nitrogen supply. [conclusion] for maize hybrids with different nutrient characteristics, There are significant genotypic differences in the response of seedling roots to different kinds of nutrients, and different fertilizer measures can be taken according to the characteristics of varieties in order to realize their biological potential.
【作者单位】：沈阳农业大学农学院;教育部植物土壤相互作用重点实验室/中国农业大学资源与环境学院;
【基金】：公益性行业(农业)科研专项经费项目(201503116) 国家自然科学基金(31572186)资助
【分类号】：S513

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