基于BSA-seq和RNA-seq挖掘西瓜抗蔓枯病候选基因

打开文本图片集

Mining Candidate Genes for Gummy Stem Blight Resistance by BSA-seq and RNA-seq in Watermelon （Citrullus lanatus）

，CHENYifan，LIUJinqiu，，，， （InstituteofVegetable，JiangsuAcademy ofAgricultural Sciences /JiangsuKeyLaboratory forHorticultural Crop Genetic Improvement，Nanjing210014）

Abstract： Gummy stem blight is one of the major diseases threatening watermelon production.Identifying and utilizing resistance genes to gummy stem blight is of great significance for the innovationofdisease resistant watermelon germplasmand breeding ofresistant watermelon varieties.In this study，arecombinant inbred line （RIL）population derived from the crossbetween the gummy stem blight resistant germplasm PI189225 and the susceptible germplasm K3 was used as the experimental materials.Bulked segregant analysis （BSA）combined with whole genome resequencing of the parents and resistant and susceptible bulks was performed to identify candidate genomic regions associated with gummy stem blight resistance.Additionally，transcriptome sequencing （RNA-seq） data were integrated to minecandidate genes.The results showed that BSA-seq analysis identified genome regions significantly asociated with gummy stem blight resistance on chromosome 5and 10， with a total length of 8.18Mb containing 681 genes.Functional analysis revealed that these genes are primarily involved in biological proceses such as plant-pathogen interactionand phenylpropanoid biosynthesis.Further analysis using InDel markers and recombinant individuals narrowed down the resistance interval to a 2.45Mb regiononchromosome10，flankedbythemarkersChr10_30103333and Chrl0_32554279.Combined with differentially expressed genes in watermelon responding to gummy stem blight infection，six candidate genes wereidentifiedonchromosome 10.qRT-CRanalysis indicated thattheexpressionofallsixcandidate genes was induced by gummy stem blight pathogen.Among them，Cla97C10G200140and Cla97C10G202140 were highly expressed in susceptible parent，whereas Cla97C10G200100，Cla97C10G201690，Cla97C10G202570，and Cla97C10G201940 were highly expressed in the resistant parent.The findings of this study provide important theoretical basisand geneticresources for marker assisted selectionand breeding of gummystem blight resistant watermelon varieties.

Keywords：watermelon;gummy stem blight;BSA-seq;RNA-seq;candidate genes

西瓜[Citrullus lanatus（Thunb.）Matsum.&Nakai是葫芦科的重要作物，广泛种植于全球温带和热带地区。（剩余17409字）