欧亚国际

科学家利用Videometer公司构建的Radimax原位根系多光谱成像系统发表了题为Semifield root phenotyping: Root traits for deep nitrate uptake的文章，文章发表于Plant，Cell&Enviroment，这是利用该系统发表的第6篇文章。

歌本哈根大学构建的型表型设施(RadiMax)用于在半田间条件下研究根系生长以及土壤资源获取。设施包括4个单元，每个单元面积为400m2，分别安装有150根微根管，允许对0.4 m–1.8 m或 0.7 m–2.8 m土壤深度间隔的根进行观察。根系观测通过多光谱微根光成像系统实现。植物生长行与水分梯度垂直，设施安装有多深度亚灌溉系统以及移动雨棚。水梯度可实现将根观测与冠层胁迫反应进展相关联。

半田间根系表型：深层硝酸盐吸收的根系特征

摘要

深根冬小麦基因型可以减少硝酸盐淋失，增加氮素吸收。我们旨在研究哪些深根性状与深氮吸收相关，并估计根系性状和深层15N示踪吸收的遗传变异。两年内，冬小麦基因型在半田间根系筛选设施RadiMax中生长。在主要生长季节进行了三次微根管根系成像。开花时，在1.8m深，通过地下滴灌注入15N 。对注射区域上方的成熟麦穗进行15N含量分析。根据基于微根管（minirhizotron）图像的根长数据，构建了82个性状，描述了根的深度、密度、分布和生长情况。用LASSO回归分析了它们预测的15N吸收的能力。根系性状预测了2年内示踪物吸收变化的24%和14%。根系性状和基因型对示踪剂的吸收均有显著影响。2018年，基因型和三个LASSO选择的根系性状预测了示踪剂吸收变化的41%，2019年，基因型和一个根系性状预测为48%。在这两年间，一个根系性状显著地介导了基因型对示踪剂吸收的影响。minirhizotron图像中的深根性状可以预测深氮吸收，表明培育深氮吸收基因型的潜力。

Semifield root phenotyping: Root traits for deep nitrate uptake

Tomke S. Wacker,Olga Popovic,Niels A. F. Olsen,Bo Markussen,Abraham G. Smith,Simon F. Svane,Kristian Thorup-Kristensen

http://doi.org/10.1111/pce.14227 

Abstract

Deep rooting winter wheat genotypes can reduce nitrate leaching losses and increase N uptake. We aimed to investigate which deep root traits are correlated to deep N uptake and to estimate genetic variation in root traits and deep 15N tracer uptake. In 2 years, winter wheat genotypes were grown in RadiMax, a semifield root-screening facility. Minirhizotron root imaging was performed three times during the main growing season. At anthesis, 15N was injected via subsurface drip irrigation at 1.8 m depth. Mature ears from above the injection area were analysed for 15N content. From minirhizotron image-based root length data, 82 traits were constructed, describing root depth, density, distribution and growth aspects. Their ability to predict 15N uptake was analysed with the least absolute shrinkage and selection operator (LASSO) regression. Root traits predicted 24% and 14% of tracer uptake variation in 2 years. Both root traits and genotype showed significant effects on tracer uptake. In 2018, genotype and the three LASSO-selected root traits predicted 41% of the variation in tracer uptake, in 2019 genotype and one root trait predicted 48%. In both years, one root trait significantly mediated the genotype effect on tracer uptake. Deep root traits from minirhizotron images can predict deep N uptake, indicating the potential to breed deep-N-uptake-genotypes.