The Color Material Channel option determines the interaction between existing material channels and the vertex colors you assign. For all options other than None, lighting affects the object's shading. The Color Material Channel options are as follows:
None of the material properties of the shader(s) assigned to the object are used. In this case lighting is also disabled.
The ambient material channel of the assigned shader(s) is overridden by the vertex color.
The ambient and diffuse material channels of the assigned shader(s) are overridden by the vertex color.
The diffuse material channel of the assigned shader(s) is overridden by the vertex color. This is the default setting.
The specular material channel of the assigned shader(s) is overridden by the vertex color.
The emission material channel of the assigned shader(s) is overridden by the vertex color.