Analysis Of The Differential Mechanism Of Fall Dormancy In Alfalfa Based On Transcriptome And Proteome Sequencing

Alfalfa（Medicago sativa L.）is a leguminous forage grass widely cultivate d worldwide,and it has autumn dormancy characteristics.At present,research on the mechanism of autumn dormancy in alfalfa is mainly focused on physiol ogical and ecological processes,but less research has been reported on the reg ulation of related gene expression pathways and protein effects.In this experim ent,we investigated the mechanism of autumn dormancy in alfalfa through mo rphological characteristics of non-autodormant alfalfa variety JD60（autumn dor mancy level 9）and autumn dormant variety JD36（autumn dormancy level 2）as well as transcriptome sequencing and proteome sequencing studies,and the results were as follows.1.The above-ground part of the non-autodormant variety JD60 grew faster and had a better growth trend than the autodormant variety in the face of low temperature environment,while the autodormant variety JD36 grew slowly and showed a prostrate state in the face of low temperature environment,but the r oot growth of the autodormant variety was better than that of the non-autodor mant variety JD60,and there were also significant differences between the leav es of the two varieties,with the leaves of the non-autodormant variety JD60 b eing longer than those of the autodormant variety JD36 The leaf of non-autum n dormant variety JD60 was longer than that of autumn dormant variety JD3 6（p<0.05）,but the width was not significantly different（p>0₀5）.2.The hypocotyl lengths of autumn-dormant and non-autumn-dormant vari eties were not significantly different at 20℃（p>0.05）,but significantly differen t at 4℃（p<0.05）.In addition,the cell structure of hypocotyl of autumn-dorma nt and non-autumn-dormant varieties was compared by paraffin section,and the cells of autumn-dormant variety were arranged closely and regularly,while the cells of non-autumn-dormant variety were irregular in size and hollow in the middle of hypocotyl,and the degree of lignification was deepened.3.The lignin and cellulose contents of non-fall-dormant varieties were signi ficantly（p<0.05）higher than those of fall-dormant varieties,but the carbohydra te contents were significantly（p<0.05）lower than those of fall-dormant varietie s,and the relative feed value was also significantly（p<0.05）lower than that o f fall-dormant varieties.4.The Illumina sequencing platform was used to sequence the transcripto me of the terminal buds of two alfalfa varieties,autumn dormant and non-autu mn dormant,and 522 differential genes were screened（p<0.05）.Among them,319 differential genes were annotated to the GO is database,and 16 GO path ways were significantly enriched（p<0.05）,mainly in non-membrane organelles,isocytic components,and some biological functions of sugar metabolism.119 d ifferential genes were annotated to the KEGG database,and the KEGG pathwa ys significantly enriched（p<0.05）were glutathione metabolism,phytopathogen i nteractions The nine kegg pathways significantly enriched（p<0.05）were glutath ione metabolism,phytopathogen interaction,phenylalanine metabolism,phytohor mone signaling,and α-linolenic acid metabolism.5.Applying TMT quantitative technology for proteome sequencing,JD60 co mpared with JD36 screened a total of 8910 differential proteins,129 differentia 1 proteins annotated by GO database（p<0.05）and 58 differential proteins annot ated by KEGG database（p<0.05）.GO pathways were mainly enriched in chec kpoint clamp complex,and other metabolic processes and enzyme activities.K EGG pathways were significantly enriched（p<0.05）in eight pathways:linoleic acid metabolism,α-linolenic acid metabolism,serine metabolism,isoquinoline al kaloid biosynthesis,tropane,piperidine and pyridine alkaloid biosynthesis,glyci ne,serine and threonine metabolism,β-alanine metabolism,and glutathione met abolism.