Physiological Response And Cloning Of PtWRKYs In Phormium Tenax And Their Expression Under Drought Stress

Phormium tenax is the growth of perennial perennial plants throughout the year which was growed in New Zealand at first.The breeding is mainly by ramets and few seeds.Phormium tenax is a foliage plant,and its strong adaptability and rich leaf color are widely used in landscape architecture.Phormium tenax is now not only used in garden,park,flower bed,but also used as cutting leaves in flower arrangement.Therefore,the study of drought resistance physiological resistance of Phormium tenax maize contributes to its better application in the garden,and its natural high drought resistance also helps us to excavate its resistance gene and apply it to other plants.In this study,the physiological responses of two colors of Phormium tenax in continuous soil drought stress were studied by using the test method of potted water control,and the results were compared.A new generation of high-throughput sequencing technology,Illumina HiSeq 2500,was used to sequencing the Phormium tenax harpint transcripts to obtain a database with complete open reading frames.RT-PCR was performed.A new WRKY transcription factor was cloned,named PtWRKY8 and PtWRKY10,respectively.And its expression in roots and leaves was measured by qRT-PCR technique.The main findings are as follows:The leaf water retention,chlorophyll stability index(ChI)and cytoplasmic membrane relative permeability(PMP)were higher in the physiological indexes of drought resistance evaluation of two species of Phormium tenax,and the leaf water saturation deficit,MDA(LRWC),protective enzyme activity(superoxide dismutase SOD,peroxidase POD,catalase CAT)and osmotic adjustment substances(proline Pro,soluble sugar)have a certain reliability.In the study of two species of Phormium tenax,it was found that the red Phormium tenax was superior to the green Phormium tenax in drought tolerance,and both of the two spices' drought resistance were strong.A total of 12.48 Gb Clean Data was obtained by RNA-seq sequencing,and the percentage of Q30 base was at least 92.59%.The original data was collected by De novo and finally we got 75,265 Unigene.Among them,11,058 pieces of Unigene are 1 kb length or more.By commentary of Unigene,including a comparison of NR,Swiss-Prot,KEGG,COG,KOG,GO and Pfam databases,we finally got a total of 30,814 Unigene annotations.Among them,the unigenes annotated to the GO and COG databases were 16,809 and 9,204,respectively,and 6334 Unigenes were involved in the KEGG metabolic pathway in 117 KEGG metabolic pathways.Two WRKY transcription factors,named PtWRKY8 and PtWRKY10,were cloned from Phormium tenax leaves by qRT-PCR and RACE.The full length of PtWRKY8 gene was 858 bp and contained a complete open reading frame of 1 bp encoding amino acids.The full length of PtWRKY10 gene was 237bp,encoding an amino acid.Real-time quantitative RT-PCR analysis showed that PtWRKY8 and PtWRKY10 were expressed in Phormium tenax root and leaf,and the expression level of the two genes in roots was higher than that in leaves.While the expression levels of PtWRKY8 in leaves and root were higher than PtWRKY10.The abundance of PtWRKY8 and PtWRKY10 was closely related to the drought resistance of Phormium tenax.