植物学报2024，Vol.59Issue(3)：422-432,11.DOI:10.11983/CBB23141
矮牵牛花朵大小遗传规律及相关基因的表达分析
Inheritance Analysis of Flower Size and Expression of Related Genes in Petunia hybrida
摘要
Abstract
Flower size is a key factor in plant evolution and speciation,and also an important trait that determines plant ornamental value,so it is of great scientific significance and practical value to study the inheritance law and regulatory mechanism of floral size.To clarify the inheritance law of flower size in petunia,the inbred lines and wild species of Pe-tunia hybrida with different flower sizes were used to make cross combinations and construct genetic populations in this study,including large-flowered line x medium-flowered lines(W × S26 and W × S)and large-flowered line × small-flowe-red line(W × S6).The results showed that all F1 generation of W x S26 were large-flowered plants,while the flower size appeared separation in F2 population with the ratio between large-and medium-flowered individuals of about 3:1,and the segregation ratio between large-and medium-flowered plants was close to 1:1 in the BC1 backcross population.For the W x S combination,all F1 individuals were large-flowered,while the flower size appeared separation in the F2 population,with large-to medium-flowered plants close to 2:1.The F1 progenies of W x S6 are all medium-flowered plants,while the flower size of the F2 generation showed evident variation and continuous distribution.Performing mixed major gene plus polygene inheritance model analysis,the optimal models for W x S26 and W x S combination were 1MG-AD and 2MG-EAD,respectively,according to the standard of minimum AIC value.It is reasonable to conclude that the large flower trait of the inbred line W is controlled by a single dominant gene related to the middle flower trait of S26,with addi-tive dominant effect,whereas the large flower of the inbred line W is controlled by two major genes related to the small flower of the inbred lines with equal additive dominant effect.In addition,nine genes that may regulate flower size of pe-tunia were selected based on the transcriptomic analysis of large and small flowers,and their expression levels were detected in the petals of various strains with different flower sizes by qRT-PCR.The results showed that the expression levels of cytokinin receptor gene PhHK and Type-A RRs in response to cytokinin signal were generally higher in large flowers than in medium and small flowers,suggesting that cytokinin signaling pathway may be a key factor involved in regulating the large flower trait in petunia.关键词
矮牵牛/花朵大小/遗传规律/细胞分裂素信号途径Key words
petunia/flower size/inheritance law/cytokinin signaling pathway引用本文复制引用
孙苗苗,张蔚,张林霞,霍竣涛,李志能,刘国锋..矮牵牛花朵大小遗传规律及相关基因的表达分析[J].植物学报,2024,59(3):422-432,11.基金项目
广东省自然科学基金面上项目(No.2019A1515011840)和广州市林业和园林局部门预算项目(No.穗财编[2024]4号) （No.2019A1515011840）
