Transpiration water-consumption characteristics of five kinds of landscape ground cover plants in Hunan, southern China.

The research aims to master water consumption characteristics of 5 kinds of ground cover plants in water shortage season in Hunan and provide the basis for determination of rational irrigation system and configuration mode. Water controlling experiment was used to measure the transpiration rate of Zoysia matrella,Cuphea hyssopifolia,Ophiopgon japonicus,Reineckea carnea and Zephyranthes candida by pot experiment through simulating plant growth process under different soil water and light conditions. Results showed that 4 kinds of soil water gradient were recognized,i. e. sufficient water supply,slightly water deficiency,medium water deficiency and serious water deficiency,according to variation of transpiration rate and growth status of plants. Different soil water potential corresponding to the soil water gradient was -0.20-0.03 MPa,-0.54-0.20 MPa ,-1.38-0.54 MPa and -1.38 MPa,respectively. In different months under the first three soil water gradient conditions,daily mean transpiration rate of C. hyssopifolia was larger than that of Z. matrella under full illumination; as for C.hyssopifolia and Z.candida,the transpiration rate was higher and most of them was in the first two position under half full illumination; as for Z. matrella,its transpiration rate was lower and most of them was in the last position; as for O. japonicus,R. carnea and Z. candida,there was small difference among them under full shade conditions. Water saving effects by controlling soil water and light intensity were significanty different,so optimized water saving irrigation mode was chosen according to water-saving benefit and practical needs.