Transcriptome Analalysis Of Strawberry(Fragaria×Ananasa) After Inoculation With Colletotrichum Gloeosporioides And Functional Identification Of FaPR1

Strawberry has high nutritional and economic value and is an important horticultural crop widely cultivated worldwide.Strawberry anthracnose is the most harmful disease in strawberry production,which causes huge production losses every year.Mining disease resistance genes and breeding high-quality strawberry varieties are the fundamental way to solve the problem of strawberry anthracnose.At present,the research on strawberry anthracnose resistance at home and abroad mainly focuses on the pathogen identification,field control agent screening and other aspects,and the molecular mechanism of strawberry anthracnose resistance is not clear,and the lack of systematic research.This study,on the basis of different varieties of strawberry anthracnose resistance evaluation,the transcriptome of strawberry response of Colletotrichum gloeosporioides(C.gloeosporioides)infection analysis,mining disease genes,and the gene cloning,plant expression vector construction,strawberry genetic transformation and transgenic strawberry identification,clear disease resistance related gene function,preliminary explore the molecular mechanism of strawberry anthracnose resistance,lay the foundation for strawberry anthracnose resistance breeding.The main study results are as follows:1 Evaluation of anthracnose resistance in different strawberry varietiesThe anthracnose resistance of 20 strawberry varieties was identified and evaluated,and the results showed that the disease resistance of different varieties varied greatly,among which,‘Zhang Ji’,‘Red Face’,‘Feng xiang’ and ‘Saga Qing Qing’ had a high disease index,which showed disease.‘Maria’,‘Sweet Charlie’,‘All-Star’,‘Wistar’,‘Daselleket’,‘Todra’,‘Dukla’ and ‘Meisha’ eight varieties had low disease index and high resistance,among which ‘Maria’ had the lowest disease index and the strongest disease resistance.The remaining eight varieties showed medium resistance2 Transcriptome analysis of strawberry responsive to C.gloeosporioides inoculationExtensive transcript information was obtained by sequencing of ‘Maria’ strawberry samples seeded with 0 d,1 d,3 d,5 d,and 7 d using high-throughput transcriptome sequencing technology.An enrichment of KEGG pathway genes with varying levels of expression revealed that the most significant enrichment was seen in phytohormone signal transduction pathways.Analysis of these genes in the phytohormone signaling transduction pathway showed that the Fa PR1 gene had the greatest differential expression.3 Cloning and sequence analysis of the Fa PR1 geneThe Fa PR1 gene was cloned by RT-PCR and encoding a protein of 162 amino acids with an isoelectric point(PI)of 5.52.Phylogenetic analysis showed that Fa PR1 protein is closely related to Rc PR1 and Rh PR1,with 86.42% similarity to Rc PR1 and80.25% similarity to Rh PR1.Subcellular localization results showed that the Fa PR1 protein is localized in the nucleus and cytoplasm.4 Identification of the Fa PR1 interaction proteinsBased on the results of the differential expression analysis in the transcriptomic data and the interaction pair included in the STRING database,Fa TLP1 is predicted as a potential interaction protein of Fa PR1,and the interaction relationship between Fa TLP1 and Fa PR1 was verified using a yeast double hybrid method,which showed an interaction relationship between Fa TLP1 and Fa PR1.5 Fa PR1 gene-transformed strawberry and functional characterizationThe Fa PR1 gene was transferred to the diploid strawberry ‘Hawaii 4’ and the phenotypic and physiological changes of wild-type and strawberry material overexpressed Fa PR1 gene after the infection.The results showed that the relative conductivity of material and MDA content of Fa PR1 strawberries were significantly less than that of wild-type strawberries,and the vitality of SOD,POD and CAT were significantly higher than that of wild-type strawberries,indicating that overexpression of Fa PR1 could reduce the damage caused by pathogen infection.In addition,the phenotypically expressed Fa PR1 gene strawberry materials also showed significantly higher disease resistance than the wild-type materials.The above results indicate that Fa PR1 gene plays an important role in strawberry against anthrax,and the overexpression of Fa PR1 gene can enhance the resistance to anthracnose in strawberry.