Effect of waterretaining agent on the growth and physiological metabolism of Sedum sarmentosum

The effects of waterretaining agent (WRA) on the growth and physiological metabolism of Sedum sarmentosum were studied through adding WRA to the substrate (vermiculite, peat, coal ash with the same volume). The results showed that the application of WRA promoted the bud germination and elongation and increased the contents of photosynthetic pigments, the leaf relative water content, the free amino acid contents and the root vigor. And the dry matter accumulation was improved as well. It was more significant for increasing the accumulation of dry matter, the growth of aboveground part, the leaf relative water content and the amino acid contents under drought condition. However, the high dosage would reduced the root vigor. The suitable amount of WRA used in the roof turfgrass of Sedum sarmentosum was 1 g/L.