Creating Male Sterile Lines Of Rice Using The Genome Editing Technololgies

Using of heterosis is one of the most important way to improve theyield of rice.At present there are two main methods including the 'three-line' and 'two-line' system to utilize heterosis of rice.But there are just limited variety can be used in the 'three-line'system and breeding three-line hybrid rice is time consuming.In the 'two-line'system,thechanging weather or extreme weather changes bring a lot of trouble to two high-yielding hybrid rice.Stable sterility characteristic of recessive genic male sterile(RGMS)lines,basic is not affected by the environment,is an ideal material used as a sterile lines.While its sterility characteristic cannot be maintained,RGMS lines cannot be used in seed production.To solve this problem,this study design a system named intelligent sterility/maintain system to make use of RGMS line.Firstly,we created RGMS mutations by genome-editing technique.Then construct a vector which contain pollen lethal gene,fertility gene and herbicide-resistant gene and transform the vector into the RGMS mutations.The transgenic plant can be used as the maintainer lines.The results were listed as below:1.Got 16,27,36,10,18 mutant strains and each gene has 6,14,13,7,7 mutants,and the average of each gene mutation rate were 31.5%,81.2%,37.5%36.7%and 31.8%respectively.Most mutations are mainly concentrated in the double allelic mutation,and given priority to with base insertions or deletions.Among them,the lack of base and base insert each 37.7%and 31.1%of total mutation types.Most mutations length is given priority to with the insert or lack of a single base(accounting for 40.6%of the total mutation).In addition,each mutant gene mutation position before PAM sequence usually 3-4 nt base insert,deletions or replacement.2.Observing the morphological characteristics and pollen sterility of the homozygo us mutations of T,gneration plants,founding that the mutant plant had not happe ned morphological changes.The MIL1 and OsUGPl gene mutant were completly ab ortive.RAFTIN gene mutant was not entirely abortive.UDT1 and OsIPA1 mutants has not been observed the male sterility of T1 plants because of time.3.Building an intelligent engineering maintainer line carrier to make the pollen let hal genes,herbicide gene and wild type UDT1 series built in single carrier p1300-UEM T-DNA area.The work of introducing the intelligent engineering maintainer line carrier into the UDT1 mutant is under way,and it is expected to establish a sterile/maintainer lines for UDT1 male sterility.In addition to remove selection m arkers,this study also plans to construct a double T-DNA plant expression vector.A nd make the pollen lethal genes,herbicide gene in series built in the double T-D NA carrier pDTM3-UEM,and then is only need to introduce the fertility genes in to its.This study laid a solid foundation for the final establishment of a set of intel ligent engineering to maintain the Recessive Male Sterility of rice.