The Effect Of MCP On Improving Drought Resistance In Sugarcane Seedling Stage

In the present expriment, sugarcane varieties ROC22was used as expimential materials. In a closed in the artificial climate chamber, sugarcane seedlings was treated with concentration of1mg/L of methyl propylene (1-MCP) respectively on a treatment and secondary treatment in sugarcane seedling stage. The physiological and biochemical index and chlorophyll fluorescence parameter were analyzed. The expresion of amp-activated protein kinase (MAPK) gene also was disicussed by using semi-quantitative PCR detection method. The results are as follows:1. Under drought stress and after lmg/LMCP treatments, leaf water potential maintained in high level, and kept the water absorbing capacity of plant cells and the normal physiological metabolism under drought stress; Can effectively maintain a lower level of the cell membrane permeability and MDA content, to maintain the integrity of cell membrane; Prompted the sugarcane leaf rapid accumulation of proline content, to prevent the sharp rise in soluble sugar content and accumulation, and delay the degradation rate of the sugarcane leaf soluble protein, thereby increasing cell inside and outside osmotic regulation ability to resist drought stress. And under the condition of normal water supply to use MCP of sugarcane leaf water potential, sugar cane, sugar cane leaf proline content in leaf cell membrane permeability was impact is not big, but will be a small amount of malondialdehyde content, the soluble sugar and soluble protein has certain promoting accumulation effect.2. Under normal water supply condition, the POD and SOD activities increased after1mg/L MCP treatments, and on contrary for the CAT activity. It was contrary under the drought tress, the activity of POD, SOD, CAT mproved after lmg/L MCP treatments. 3. Under the normal water supply condition, the chlorophyll content significantly increased after the secondary treatment with MCP. There was significantly difference for the one-time treatment with MCP. When not under drought stress, application of MCP of Fv/Fm, Yield, after processing of ETR, qP and qN the chlorophyll fluorescence parameters changed little compared with controls. But in the process of soil drought stress, compared to controls, application of MCP treatment can effectively alleviate the degradation of the sugarcane leaf chlorophyll content after speed, delay the sugarcane leaf Fv/Fm, parameters such as Yield, ETR, qP, reduce the rise of qN.4、under the condition of normal water supply, sugarcane leaf SoMAPK4the expression of genes in the transcriptional level is influenced by MCP treatment once, and after secondary treatment showed a trend of lower the gene expression. In drought stress, MCP of sugarcane leaf SoMAPK4gene transcription in the expression of the quantity produced increase after decreases first, the dynamic change trend of increase or decrease together.To sum up, the sugar cane in seedling stage under drought stress, with MCP can improve sugarcane in the short term drought resistance related to the physiological and biochemical indices and the chlorophyll fluorescence parameters, so as to improve the drought-resistant ability of sugarcane seedling stage. Research results show that when using sugar cane in seedling stage under drought stress, with MCP secondary processing to sugar cane drought resistance for longer than a treatment, the effect is more obvious.