Effects Of Planting Density And Sowing-date On Growth And Secondary Metabolites Accumulation Of Astragalus Mongholicus

Reasonable planting density and sowing-date have great influence on high yield and high quality of medicinal plants. In this study, we focusing on Astragalus mongholicus, by doing field experiments, we showed the effects of density and sowing-date on development and secondary metabolites of Astragalus mongholicus. What we did would determine the optimum density and sowing-date, and provide theoretical basis for the standardization of the Mongolian astragalus cultivation. The primary results are as follows.The planting density has significant influence on growth and secondary metabolites accumulation of Astragalus mongholicus, the ground parts development is predominant in the early stage. And in the late stage, plants give priority to root development, in addition, planting density of 20 cm × 20 cm is conducive to vigorous growth in each growth stage of Astragalus mongholicus and obtain the highest yield; Planting density can also affect the accumulation of flavonoids, saponins and polysaccharides of secondary metabolites, planting density of 20 cm × 20 cm and 20cm×25cm can promote the accumulation of secondary metabolites of Astragalus mongholicus root, optimize its quality, and improve the efficacy. So planting density of 20 cm × 20 cm is conducive to achieve high quality and high yield.The sowing-date has significant influence on growth, quality and yield. Accompanied the sowing-date delaying, the stay time of the different development stage also changed. The development of ground parts and the root of Astragalus mongholicus are most eugenic to sow on May 10 th. And it also can obtain the highest yield when sowing on May 10 th. The higher content of total flavonoids, saponins and polysaccharide are both the sowing-date treatment of May 10 th. So we demonstrate that ecological conditions like temperature, illumination are most appropriate when plant on May 10 th. This treatment can be conductive to the growth, the accumulation of dry matter and the increase of the effective components. And it can also ensure the yield and inner quality of Astragalus mongholicus be stable and effective.