在碱性溶液中，凡分子中含二个或二个以上酰胺基(—CO-NH2)或与此相似基团的化合 物均与二价铜离子作用，络合物呈紫色，这一反应称双缩脲反应。蛋白质分子含有众多肽 键(—CONH—)，可发生双缩脲反应，且呈色强度在一定浓度范围内与蛋白质含量成正比， 经光谱扫描 540nm 为最大吸波长。

   可见分光光度计、1mL 玻璃比色皿（光径 1cm）、台式离心机、恒温水浴锅、移液器。

1.《Evaluating physiological changes of grass and semishrub species with seasonality for understanding the process of shrub encroachment in semiarid grasslands》.2021.《Functional Plant Biology》.IF=3.1

2.《Transcriptome and Co-expression Network Analyses Reveal Differential Gene Expression and Pathways in Response to Severe Drought Stress in Peanut (Arachis hypogaea L.)》.2021.《Frontiers in Genetics》.IF=4.6

3.《Resveratrol improves the iron defciency adaptation of Malus baccata seedlings by regulating iron absorption》.2021.《BMC Plant Biol》.IF=4.2

4.《Effects of root characteristics on panicle formation in japonica rice under low temperature water stress at the reproductive stage》.2021.《Field Crops Research》.IF=5.224