Effects Of Iron On The Expression Of The Iron And Nitrogen Metabolism And K~+ Channel Related Genes In 'huangjin' Pear

‘huangjin' pear belongs to Chinese pear?P.pyrifolia Nakai?system.Matured by Korean Horticulture farm using the ‘xingao' and ‘twenty centry' for hybridization.Taking the advantage of strong stress resistance and high production and has been widely planted all over the country.However in China's main pear production area,such as northwest and acient yellow river course,serious soil salinization causing short supply of efficient iron which seriously affect the development of the local pear industry.Previously study has showed the Fe,N and content in chlorsis leaves are all lower than normal leaves.Also GA content in chlorsis leaves is lower than normal leaves.So,this experiment taking the ‘hangjin' pear leaves as experiment material.Measuring the activity of enzymes related in Fe,N metabolism.Analyzing the expression the genes related in the Fe,N metabolism,K⁺ channel and GA signal transduction.The GA content in leaves were measured by ELISA.The Fe,N,K content were measured by ICP-AES.The main results as follows:?1?The relative expression of the Fer1,Fer2,Fer3,Fd1,Fd2 gene in chlorsis leaves all lower than normal leaves.After FeSO₄ treatment,Chlorsis leaves started to turn green,higher content of the FeSO₄,better the results.At the meantime the relative expression of the Fer1,Fer2,Fer3,Fd1 gene all up-regulated,significantly higher than chlorsis leaves.The highest expression shows in the 3 d and 6 d in the same treatment.Fd2gene's expression up-regulated all the time during the experiment.The Fe content in leaves also improved after FeSO₄ treatment.So we can sugguest FeSO₄ treatment can improve the Fe content in chlorsis leaves then improve the relative expression of the genes in related Fe metabolism,there appears to be a link between these two.?2?The relative expression of NR,Fd-GOGAT,GLIE gene in chlorsis leaves all lower than normal leaves.After FeSO₄ treatment,NR,Fd-GOGAT,GLIE gene's expression up-regulated,significantly higher chlorsis leaves.Relative expression of NRT1.2 gene in Chlorsis leaves higher than normals.After FeSO₄ treatment,it down-regulated.The activity of NR,GS,GOGAT enzymes all enhanced after FeSO₄ treatment.The N content in leaves also improved.So we can make the estimation that FeSO₄ treatment can improve the N metabolism,improving the N content in leaves,further up-regulatin the expression related in N metabolism.?3?The relative expression of SKOR,TP11,TP3 gene in chlorsis leaves all lower thannormals,with FeSO₄ treatment,SKOR,TP11 and TP3's expression all up-regulated.SKOR and TP3 up-regulating all the time during the experiment.However,the expression of the TP11 reach the highest level in 6 d.At the same time,the FeSO₄ treatment improve the K content in leaves which further improve the K⁺channel protein.?4?The relative expression of GID13,GID15,GA2 ox gene in chlorsis leaves all lower than normal leaves.The GA content decreased after FeSO₄ treatment.So the suggestion can be made FeSO₄ treatment can decrease the GA content which further improve the expression of genes retroegulated the GA signal transduction.