A point mutation resulting in a 13 bp deletion in the coding sequence of Cldf leads to a GA-deficient dwarf phenotype in watermelon  

作　　者：Chunhua Wei Chunyu Zhu Liping Yang Wei Zhao Rongxue Ma Hao Li Yong Zhang Jianxiang Ma Jianqiang Yang Xian Zhang 

机构地区：[1]State Key Laboratory of Crop Stress Biology in Arid Areas,College of Horticulture,Northwest A&F University,Yangling,Shaanxi 712100,China

出　　处：《Horticulture Research》2019年第1期121-132,共12页园艺研究（英文）

基　　金：supported by funding from the National Natural Science Foundation of China(Grant No.31701939);the National Natural Science Foundation of Shaanxi Province,China(No.2019JQ-324);the Key Project of Shaanxi Province(2017ZDXM-NY-025);the National Key R&D Program of China(2018YFD0100704);the Modern Agro-Industry Technology Research System of China(No.CARS-26-18).

摘　　要：The dwarf architecture is an important and valuable agronomic trait in watermelon breeding and has the potential to increase fruit yield and reduce labor cost in crop cultivation.However,the molecular basis for dwarfism in watermelon remains largely unknown.In this study,a recessive dwarf allele(designated as Cldf(Citrullus lanatus dwarfism))was fine mapped in a 32.88 kb region on chromosome 09 using F2 segregation populations derived from reciprocal crossing of a normal line M08 and a dwarf line N21.Gene annotation of the corresponding region revealed that the Cla015407 gene encoding a gibberellin 3β-hydroxylase functions as the best possible candidate gene for Cldf.Sequence analysis showed that the fourth polymorphism site(a G to A point mutation)at the 3′AG splice receptor site of the intron leads to a 13 bp deletion in the coding sequence of Cldf in dwarf line N21 and thus results in a truncated protein lacking the conserved domain for binding 2-oxoglutarate.In addition,the dwarf phenotype of Cldf could be rescued by exogenous GA3 application.Phylogenetic analysis suggested that the small multigene family GA3ox(GA3 oxidase)in cucurbit species may originate from three ancient lineages in Cucurbitaceae.All these data support the conclusion that Cldf is a GA-deficient mutant,which together with the cosegregated marker can be used for breeding new dwarf cultivars.

关 键 词：DWARF breeding CULTIVAR 

分 类 号：S65[农业科学—果树学]