Review on new methods of observation and recognition in situ for crop roots

Plant roots is the vital organs which can obtain nutrients and water from the soil and support the plants body,as complexity morphology and soil opaque properties of root hinders the observation of root system,and the lack of roots observation method in situ has become the technological bottlenecks for in-depth study of roots.This paper reviewed from the two aspects of root observations and recognition algorithms.On the root observations techniques,minirhizotron method(non-destructive two-dimensional root observation) and X-ray computed tomography(XCT),three-dimensional root system architecture observation methods in situ were reviewed,and their advantages and disadvantages were showed.On the root recognition algorithms,2D root morphologic and 3D architecture recognition algorithms was analyzed,the applicability and limitation were pointed out.Finally,on the basis of in-depth analysis for the two observation and recognition technologies,it can concluded that the root observation techniques in situ with XCT in the natural soil media is the future development trends of root three-dimensional architectures quantification analysis.