Effects Of Endogenesis And Exogenous Of ABA On The Cuticle Of Rice Leaves During Vegetative Growth Period

The cuticle layers as the primary interface between plants and the environment,that is the first barrier to plants block the outside world,widely present in the leaves,flowers,stems and fruits of plants.The cuticle is mainly composed of exocuticle,corner layer ontology and cutinized layer.The cuticle plays a protective role in plants,it can not only prevent plant non stomatal water loss,improve drought resitance,but also can keep the surface clean and prevent ultraviolet,high temperature and the high salt stress tolerance,and resistance to pests and diseases.ABA as an important plant hormone,it can regulate plants growth and biotic and abiotic stresses,as in reponse to drought,salinity,and plays an important role in the process of chilling injury.It was found that overexpression of AtNCED3,the key gene of ABA synthesis in Arabidopsis,resulted in the increase of endogenous ABA content and the change of stratum corneum.In this study,the wild type japonica rice variety No 10(WT),the transgenic plants with Ubi1::AtNCED3 gene of L4(T2),were used as meterials cultured to 39 d,the some WT carry on spraying ABA,analyzing the relative water content,water loss rate,chlorophyll permeability,the composiyion and content of cuticle,and expression of genes related to cuticle synthesis.The results show that :Compared with wild type,(1)The extraneous ABA plants leaves are yellow,The growth of endogenous ABA plants is lower and grows more slowly and the plant is short,and the leaf texture is thick;(2)The relative water content of endogenous ABA plants > the extraneous ABA plants >the wild type plants,in vitro water loss rate : the wild type plants > the extraneous ABA plants>the endogenous ABA plants,the chlorophyll extracted rate: the wild type plants > the extraneous ABA plants>the endogenous ABA plants,(3)The content of ABA in endogenous ABA p lants is higher;(4)The TLC results shows that the bands of each component are bright of wax mixture,and the content add up,the plants water retention is increased;(5)In the extraneous ABA plants,the OsCER1 and OsONI3 gene relative expression is reduced,the relative expression of other genes was significantly higher than that of wild type(WT);according to the endogenous ABA plants,the OsGL1-3、OsWLS3、OsWR1、OsMYB91、OsABCG11 and OsHSD1 gene relative expression is increased,and there are significant differences in OsWLS3 and OsWR1 gene relative expression compared with the wild-type;the relative expression of OsMYB91 gene is not significantly different compared with the wild type,the relative expression is basically the same of OsABCG11 and OsHSD1 genes compared with wild type.