Molecular Mechanism Of Different Rootstocks On The Development Of Scion Of "Yanfu 3" Apple

Malus domestica is one of the longest-growing,most planted,and highest-yielding fruit trees in China.Apple production plays an important role in fruit production in China.As the basis of grafted fruit trees,rootstocks have an important influence on the growth potential,horticultural and pathological characteristics of apple cultivars.The study of rootstocks has been a major topic in Apple research for nearly half a century and has grown rapidly around the world.In this study,transcriptome sequencing was used to identify mRNA and miRNA related to the development of the apical meristem of Yanfu3/Baleng crab,Yanfu 3/M9 and Yanfu3 to study the mechanism of mRNA and miRNA regulation of apple growth and development.The specific experimental results are as follows:1.The growth status of Yanfu3/Baleng crab,Yanfu 3/M9 and Yanfu 3 and the growth and development related genes of the stem tip were analyzed.The content of IAA was the highest in Yanfu3/Baleng crab the fastest and longest in Primary shoot,the lowest in IAA in Yanfu 3/M9,and the slowest and the shortest in Primary shoot.The change of IAA content in the leaves of the stems was consistent with the growth of grafted grafts.The expression level of YUCCA10 a gene affects the synthesis of IAA.The expression levels of GH3.5 gene and ILR1like5 gene affect the amount of free IAA,and ARF8 transcription factor affects the activity of GH3 family gene.Compared with Yanfu3/Baleng crab,Yanfu3/M9 and Yanfu 3,the high expression of YUCCA10 a gene and the low expression of ARF8 and GH3.5 genes were observed in the Yanfu3/Baleng crab.High expression of the ILR1like5 gene results in the highest growth viability.In contrast,Yanfu 3/M9 has the lowest growth vigour.We conclude that rootstocks with different growth vigor have a significant effect on the expression of auxin signal transduction pathways and auxin synthesis in grafted plants,and then regulate hormone levels and their signaling pathways.2.We cloned the YUCCA10 a gene of M9 dwarf rootstock,Baleng crab rootstock and Yanfu 3,the YUCCA10 a genes of the three species were composed of 1149 nucleotides,and the M9 dwarfing rootstock had only one differential nucleoside with the other two species.Acid,three species of the YUCCA10 a gene deduced to encode the same protein.3.According to miRNA sequencing and quantitative expression analysis of target genes,the low expression of miR160 and miR166 and the high expression of target genes in Yanfu 3/ Baleng crab promoted the development of stem apical meristem and increased its growth potential.The high expression of miR160 and miR166 and the low expression of target genes in Yanfu 3/M9 inhibited the development of stem apical meristem.The high expression of miR167,miR171,miR172 and the low expression of target genes in Yanfu 3/ Baleng crab increased the development of stem meristem and increased its growth potential.The low expression of miR167,miR171,miR172 and the high expression of its target gene in Yanfu 3/M9 inhibited the development of stem apical meristem.