Experimental research on effect of surface and subsurface waterlogging in stage of cotton flowering and boll set on yield

In the regions vulnerable to surface and subsurface waterlogging, the stage of cotton flowering and boll set is just in rainy season. Cotton often meets comprehensive stress from surface and subsurface waterlogging. It makes a greater influence upon the growth and yield of cotton. The problem was studied via test-pit experiment. And 4 models of dominated drainage indices were established for those farmland, which are vulnerable to surface and subsurface waterlogging. The dominated drainage indices that combine surface and subsurface waterlogging were given preliminarily. And the indices that reflect control combining surface waterlogging and subsurface waterlogging were discussed.