Investigation of Differences in Fertility among Progenies from Self-Pollinated Chrysanthemum

Abstract

Most chrysanthemum cultivars are self-incompatible, so it is very difficult to create pure lines that are important in chrysanthemum breeding and theoretical studies. In our previous study, we obtained a self-compatible chrysanthemum cultivar and its self-pollinated seed set was 56.50%. It was interesting that the seed set of its ten progenies ranged from 0% to 37.23%. Examination of the factors causing the differences in the seed set will lead to an improved understanding of chrysanthemum self-incompatibility, and provide valuable information for creating pure lines. Pollen morphology, pollen germination percentage, pistil receptivity and embryo development were investigated using the in vitro culture method, the paraffin section technique, scanning electron microscopy and transmission electron microscopy. Moreover, RNA sequencing and bioinformatics were applied to analyzing the transcriptomic profiles of mature stigmas and anthers. It was found that the self-pollinated seed set of “Q10-33-1①”,”Q10-33-1③”,”Q10-33-1④” and “Q10-33-1⑩” were 37.23%, 26.77%, 7.97% and 0%, respectively. The differences in fertility among four progenies were mainly attributable to differences in pollen germination percentage and pistil receptivity. Failure of the seed set in “Q10-33-1⑩” was possibly due to self-incompatibility. In the transcriptomic files, 22 potential stigma S genes and 8 potential pollen S genes were found out.

Mitotically heritable epigenetic modifications of CmMYB6 control anthocyanin biosynthesis in chrysanthemum

“…Chrysanthemum morifolium is a common horticultural plant that is grown world‐wide, especially in China (Teng et al ., 2008), where it has been the cultivated and has undergone traditional breeding to improve its flower color over the last 2000 yr (Silva, 2006). However, the development of elite cultivars of chrysanthemum is difficult, given its outcrossing habit and high heterozygosity (Wang et al ., 2018). Chrysanthemum improvement is heavily dependent on clonal propagation, limiting the development of breeding programs.…”

Effect of Parental Components and Pollination Frequency on the Setting and Germination of Chrysanthemum Seeds

“…However, in chrysanthemums, it is ineffective due to the plants' sporophytic self-incompatibility (SI) and lack of viable pollen or inability of pollen to germinate in the style [9][10][11]. Most of the modern cultivated chrysanthemums are self-incompatible and their trait inheritance and genetic background are extremely complex [12,13]. Therefore, it is very difficult to create pure lines [13].…”

“…Most of the modern cultivated chrysanthemums are self-incompatible and their trait inheritance and genetic background are extremely complex [12,13]. Therefore, it is very difficult to create pure lines [13]. Self-incompatibility, also called self-infertility, means the inability of a fully fertile hermaphroditic plant to produce zygotes when self-pollinated [14].…”

Phenotypic Characterization and RT-qPCR Analysis of Flower Development in F1 Transgenics of Chrysanthemum × grandiflorum

“…Additionally, several new chrysanthemum species are being produced through this method annually [ 8 , 9 ]. Despite the fact that various chrysanthemum cultivars are being produced by conventional hybridization techniques, the species is an allohexaploid and self-incompatible (with 3 S alleles) [ 10 , 11 , 12 , 13 , 14 ].…”