Distribution of and damage caused by yellow stunt and root rot of Astragalus adsurgens in five northern provinces of China Progress and prospect in studies on Embellisia Influence of Medicinal Plant Extracts on the Inhibition Activity of Embellisia astragli and the Seed Germination of Astragalus adsurgens Effect of exogenous hydrogen peroxide on resistance of Astragalus adsurgens to yellow stunt and root rot disease