AUTHOR=Li Zixuan , Mao Chenyuan , Wu Xinyi , Zhou Haoqing , Zhao Kunkun , Jiang Jiafu , Chen Sumei , Fang Weimin , Guan Zhiyong , Zhang Jing , Liao Yuan , Wang Zhenxing , Chen Fadi , Wang Haibin 

TITLE=Hybrid weakness and continuous flowering caused by compound expression of FTLs in Chrysanthemum morifolium × Leucanthemum paludosum intergeneric hybridization

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1120820

DOI=10.3389/fpls.2023.1120820

ISSN=1664-462X

ABSTRACT=<p>Hybridization is an important evolutionary mechanism ubiquitous to plants. Previous studies have shown that hybrid polyploidization of cultivated chrysanthemum, ‘Zhongshanzigui’, and <italic>Leucanthemum paludosum</italic> exhibit spring-flowering traits. This study explores the function of the LpFTLs gene via the phenotype of A. thaliana after heterologous transformation of the LpFTLs gene, and analyzes the mechanism ofthe continuous flowering phenotype and heterosis of hybrid offspring. The results suggest that the flowering phenotype of hybrid offspring in spring may be related to the expression of the <italic>LpFTLs</italic> gene. Ectopic expression of <italic>Leucanthemum paludosumLpFTLs</italic> in <italic>Arabidopsis thaliana</italic> resulted in earlier flowering, indicating that the <italic>LpFTLs</italic> gene also affects the flowering time in <italic>L. paludosum.</italic> Compound expression of <italic>FTLs</italic> in <italic>C. morifolium</italic> × <italic>L. paludosum</italic> intergeneric hybridization directly leads to serious heterosis in the hybrid offspring. Moreover, continuous flowering appears to be accompanied by hybrid weakness under the balance of vegetative and reproductive growth. Therefore, in future studies on chrysanthemum breeding, a suitable balance point must be established to ensure the target flowering time under normal growth.</p>