Effects Of Auxin And Carbon Source On Root Development Of ’Beihong’,’Shuangyou’ And Muscat Grape Tissue Culture Seedlings

In order to explore the effects of auxin and sucrose on the root development of tissue cultured seedlings of ’Beihong’,’Shuangyou’ and Muscat grapes,this experiment took ’Beihong’,Vitis amurensis Rupr ’Shuangyou’ and Muscat grapes as the research objects.Under the condition of tissue culture,the effects of IBA,NAA and sucrose at different concentrations on root development,transcriptome sequencing analysis of callus at rooting stage,endogenous hormone content in root system and expression difference of IAA related genes were studied.9 groups of grape tissue culture seedlings were treated with IBA,NAA and sucrose at different concentrations.10 days after rooting treatment,when the number of roots changed rapidly,the root callus was taken for transcriptome sequencing,the root callus was taken for transcriptome sequencing.After rooting treatment for 20,30 and 40 days,the root growth indexes were measured,and the roots with uniform growth were taken to measure the content of endogenous hormones and the expression of auxin related genes.The results show that:(1)Tissue culture assays the type of culture medium that was relatively suitable for ’Beihong’,Muscat grape and,Shuangyou’ grapes rooting of mountain grapes was 1/2 Bs.The medium formulations for the 3 grape cultivars were 1/2 B5+25 g/L sucrose+0.3 mg/L NAA+0.1 mg/L IBA and 1/2 B5+25 g/L sucrose+0.5 mg/L NAA+0.5 mg/L IBA,which showed the best rooting yield.The concentration of NAA had the greatest effect on all indicators of root system,with 25 g/L sucrose+0.5 mg/L NAA+0.5 mg/L IBA being the better fit for root cultivation of three grape cultivars,Muscat grapes having the best rooting situation and ’Shuangyou’ grapes having the worst rooting condition.(2)Transcriptome sequencing analysis revealed that 977,52 and 784 differentially expressed genes of ’Beihong’,Muscat and ’Shuangyou’ grapes,respectively.The differentially expressed genes of’Beihong’ and ’Shuangyou’ grapes were dominated by upregulated expression,and the Muscat grape were dominated by downregulated expression.Regulatory genes potentially important for ’Beihong’grape rooting were selected as VvIAA,VvIAA22,VvIAA28,VvEFR,VvGH3.6 and VvPRI,the regulatory genes important for rooting ’Shuangyou ’grapes are VvIAA,VvIAA14,VvIAA22,VvIAA27,VvGH3.6.VvLAX3 and VvA-ARR.(3)The three grape cultivars showed high correlations and similar trends in the contents of ABA and GA3,which promoted the elongation growth of primary roots and inhibited the increase in the numbers of primary and lateral roots.The correlation of IAA and tZ contents was higher in the roots of the three grape cultivars,and IAA promoted an increase in the number of primary roots.(4)IAA associated gene expression levels as a whole showed an initial increase followed by a decrease,with VvTAR2,VvYUC2,VvYUC6,and VvYUC8 important for auxin synthesis.The VvABPl and VvTIR1 genes have similar expression trends and play a role in auxin signaling.VvLRPl and VvSWP1 have similar expression trends and play a role in root elongation growth.Lower sucrose concentrations promoted the expression of IAA vector associated genes VvAUX1,VvLAX1,VvPIN1,and VvABPB1.