Effects Of Saline-alkali Stress On The Physiological And Biochemical Characteristics Of Transgenic Lc-CDPK Genes Rice

High salt and alkali are the two improtant characteristics of saline soils.High osmotic potential,high pH and ionic toxic are the main stress factors.When the external environment cause harm to plant growth,plant will make corresponding responses and accumulate all kinds of osmotic regulation substances,such as proline,sucrose,betaine,mannitol and sorbitol and other small molecules.At the same time,the key enzymesto of synthesis these small molecular substances will also be changed to maintain high cell osmotic pressure.The antioxidant enzymes are produced by plants under salinity stress are SOD,POD,CAT,GR and GSH-PX.They paly an improtant role in the process of eliminates the active oxygen.CDPK is a Ser/Thr type protein kinases and widely exists in plants and protozoa.It can be activated by Ca2+ signal directly and plays an important role in normal plant growth and resistance to adversity.When plants feel stress from external environment such as salt,drought and so on,the intracellular signals are amplified and transferred to the downstream to induce the expression of the downstream gene,to change the plant physical and chemical properties and to defend the adversity.This study used the rice with Lc-CDPK gene as material,and determined the relative expression of CDPK under the different concentration of NaCl/Na2CO3 stress in the seedling stage with transfer Lc-CDPK gene rice inside to explore the optimal stress concentration for CDPK gene expression with the use of qRT-PCR technique.Under the optimal stress condition,we took the leaves and root in seeding stage and the leaves in early stage of the plants with Lc-CDPK gene as samples and measured the small molecules such as proline,cane sugar,betaine,mannitol and sorbitol content and the kay enzymes expression and activation of P5 CS,SPS and BADH,also the antioxidant enzymes SOD,POD,CAT,GR and GSH-PX activity and gene relative expression respectively.,with non-gm rice in seedling stage(CK1)as control and the rice transfer Lc-CDPK genes in early stage but without stress(CK2)as control.The main results were as follows:1.Compared with other processing conditions,the relative expression between the root and leaves of rice with Lc-CDPK gene and CDPK gene had the minimum gap and the a higher sum under the 24 h,200 mM NaCl/Na2CO3 stress.2.Seedling under saline-alkali stress,the small molecule substance contents,betaine,mannitol,sorbitol content,proline content,sugar content of Lc-CDPK gene rice were higher than CK1.And BADH?P5CS enzymes activity and gene expression were higher than CK1.Root antioxidant enzymes activity and gene expression of GR were higher than CK1.In leaf,the SOD?POD CAT?GR?GSH-PX were higher than CK1.Expression of genes were the same as enzymes activity.The antioxidant enzymes activity and expression were generally higher than that of CK1 in the leaves of rice with Lc-CDPK but showed no obvious regulation in the root.The small molecule substance content,proline,sucrose,betaine synthesis of the key enzymes and genes relative to express in rice with Lc-CDPK gene were higher than CK1,which can explain that the Lc-CDPK gene expression can effectively adjust plants to produce small molecule osmotic regulation substances and increase plant salt-tolerant ability.3.Pre-fertility under saline-alkali stress,the small molecules mannitol content,proline content,sugar content,betaine content,mannitol content in rice the Lc-CDPK gene were higher than CK2 but sorbitol content was lower than CK2.The enzymes activity of BADH,P5 CS and SPS were higher than CK2,and the gene expression of SPS was higher than that of CK2.The gene expression of BADH?P5CS were higher than CK2 at tillering stage,expression of genes were the same as enzymes activity.Antioxidant enzyme SOD,POD,CAT and GSH-PX activity and gene expression in leaves of rice with Lc-CDPK genes were higher than CK2.The enzymes GR activity and expression in tillering period of rice with Lc-CDPK genes were higher than CK2,but lower than CK2 in heading date.The antioxidant enzyme activity and the relative expression in rice with Lc-CDPK gene were higher than CK2,which can explain that salinity-alkalinity stress promotes CDPK gene regulation of plant.