| Cortaderia selloana is belong to Gramineae and it is a herb perennial. In recent years, with the development of landscaping, ornamental grasses had been paid attention more and more by designers and garden lovers.As a famous ornamental grasses, Cortaderia selloana has beautiful ideotype, evergreen and linear natural drop leaves, cone-shaped spindle inflorescence and the inflorescence can maintain a strong view to the spring. In this paper, we take Cortaderia selloana pink for materials. We study on the conditions of callus induction and plant regeneration system and then on the physiological and biochemical reactions of hot and drought stress in the hot summer conditions in Chongqing.From this study ,we laid the foundation of the genetic transformation of Cortaderia selloana; provide a prerequisite for genetic engineering breeding of Cortaderia selloana.lt is conducive to improved varieties and the development of new varieties. At the same time, it provide a reference application for the other grasses on tissue culture and landscape.First we select the explants of tissue culture. The results show that the mature seed can induct callus successfully and the callus can be differentiation and re-generation to complete plants. But the young leaves and stem can not induce callus, nor to divide the regeneration.At the same time, we explore the disinfection methods with the tissue culture. The results showed that the sterilization for seed is the 75% alcohol to deal with 20 s and the 0.1% mercuric chloride to deal with 10 min, this can achieve high germination rate and low pollution rate; the leaves disinfection methods as follows: 75% alcohol to deal with 30 s and 0.1% mercuric chloride to deal with 10 min; and the young stem segments of disinfection for: 75% alcohol to deal with 40s and 0.1% mercuric chloride processing 12min.We choose the best medium for callus induction from mature seeds is the MS and 2, 4-D 3.0 mg/L and 6- BA 0.3mg / L. In this combination of nutrients, the rate of callus induction is 78%.The callus shape is large and tidy and it is milky white and dispersion granule.We cultured callus re-differentiation and then found that the best combination of training components is MS and 6- BA 2.0mg / L and NAA0.1 mg / L. And the subculture needs MS and 6-BA 1.5mg / L and NAA 0.2mg / L. In this Condition the seedling growth fast and highly and the entirety is healthy and strong.In the rooting culture the activated carbon play a decisive role on roots. And the addition of NAA promoted root formation. It shortens the time and enhances the quality. So the best medium composition for rooting culture is 1/2MS and NAA0.8 mg / L and 6-BA 0.2 mg / L and 0.03%AC.The study on adaptation in summer of potted plants showns thatin the dual stress of high temperature and drought stress through a variety of physiological responses Cortaderia selloana can resist the initial positive response to adversity injury. With the stress-depth appeared it is unable to adapt to the phenomenon, which eventually led to the death. The specific changes are as follows: First the leaves experience the process which from green to white and dry naturally to curly stretch. It shows the adaptive responses on the hot and dry stress. And At the same time, chlorophyll content increased at first and after the lower level is always higher than the trend of the control.Under the stress the membrane system of leaf was injured, making the product of lipid peroxidation MDA continued to rise. At the same time, membrane permeability also increases. The relative conductivity has been also shown an upward trend.Under the stress the activity of SOD and POD has always above the contrast level. And the upward trend to withstand dry heat stress produced by oxygen free radicals on injured plants.Under the stress the content of soluble sugar soluble protein and proline has emerged in an upward trend. And they will transfer mutually.
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