Studies On The Inverse-resistance Of Color Ground Covers

Ground covers are the important factor in landscaping plant. They can improve the quality of afforest. In the experiment, Japanese blood grass (Cylindrica rubrum), Arrhenatherum elatius var. variega, Sedum reflexum, Sedum spectabile cv. Meteor, Weigela florida cv. Variegata and Euonymus fortuner f. gracilis were selected as the experimental materials. It was discussed the six color ground plants'breeding method, the effect on different temperature and light environments with some index such as the form and physiological, photosynthesis, anatomization of leaves. The results were summarized as follows:(1) Sedum reflexum and Euonymus fortuner f. gracilis were easy to live in cuttage. The cutting propagation of Sedum spectabile cv. Meteor and Weigela florida cv. Variegata were affected by the temperature and the degree easily, and the latter was grown better after dipped a period of time in the liquor of ABT rooting powder. Japanese blood grass and Arrhenatherum elatius var. variega were easy to live in plant division and grow better in the dormancy stage after division.In the tissue culture, Sedum spectabile cv. Meteor, Japanese blood grass, Arrhenatherum elatius var. variega and Weigela florida cv. Variegata were easy to contaminate. The first three can use the method of increasing sterilizing time, the last can add antibiotics to reduce the contamination. The best culture medium for polarization of Sedum spectabile cv. Meteor and Weigela florida cv. Variegata were both MS+ 6-BA0.50mg/L+NAA0.05mg/L, for rooting were 1/2MS+IBA0.30mg/L and 1/2MS+IBA0.50mg/L.The appropriate media for polarization and rooting of Sedum reflexum were MS+6-BA0.50mg/L+NAA0.10 mg/Land 1/2MS+IBA0.50mg/L.The appropriate media for Euonymus fortuner f. gracilis were MS+6-BA 1.00mg/L+NAA0.10mg/L and 1/2MS+NAA0.10mg/L.The appropriate media for Arrhenatherum elatius and Japanese blood grass was MS+ZT1.00mg/L+KT0.10mg/L+NAA0.10mg/L.(2) As the temperature falling, the protecting enzyme system cooperated with the osmoregulatory matter, maintaining the stability of cell membranes. The accommodation of Sedum reflexum was the strongest, Sedum spectabile cv. Meteor was the weakest. The anthocyanin content increased as the soluble sugar accumulating. Expect Japanese blood grass the chlorophyll content of the five color ground plants increased, and the contents of Sedum reflexum, Weigela florida cv. Variegata and Euonymus fortuner f. gracilis were higher. Japanese blood grass was the lowest. The photosynthesis of Sedum reflexum and Weigela florida cv. Variegata were both stronger. The change of the diameter of the leaf vessel and the thickness of the lower epidermis cell indicated significante difference, but the thickness of the upper epidermis cell, the ratio of leaf's costate vascular bundle diameter and the leaf costate diameter didn't indicate significante difference. The proportion of palisade tissue increased in bifacial leaf. And the length of bulliform cell of Japanese blood grass and Arrhenatherum elatius var. variega minished.All in all, Sedum reflexum and Arrhenatherum elatius var. variega were stronger than other plants in the cold resistance. Euonymus fortuner f. gracilis and Weigela florida cv. Variegata were weaker. And Japanese blood grass and Sedum spectabile cv. Meteor were the weakest of the six.(3) As the light weakening, Sedum spectabile cv. Meteor and Japanese blood grass represented better in form index. The proline content and soluble sugar content of Arrhenatherum elatius var. variega, Japanese blood grass and Sedum reflexum were higher than other plants. It was indicated that the shade tolerances of Japanese blood grass and Weigela florida cv. Variegata were stronger in chlorophyll content and photosynthesis, but that of Sedum reflexum was the weakest. From the light-photosynthetic curves, It was found that LCPs of Weigela florida cv. Variegata and Euonymus fortuner f. gracilis were lower, and LSP of them were higher. Sedum reflexum was representative light plant because both of LCP and LSP were higher. In the anatomization of leave, Weigela florida cv. Variegata was adapted to the shade.In a word, the shade resistance of Japanese blood grass and Weigela florida cv. Variegata were stronger, that of Euonymus fortuner f. gracilis and Sedum spectabile cv. Meteor were weaker.