*2.2. Gene Function Research*

Fei et al. identified and cloned two genes from the NCED family in *Paeonia lactiflora*, which are related to ABA synthesis in the herbaceous peony, named *PlNCED1* and *PlNCED2*. Further studies confirmed the function of the *PlNCED* gene in inducing seed dormancy and hindering seed germination [4]. In iris plants, Wang et al. confirmed the

**Citation:** Song, A.; Chen, Y. Molecular Biology of Ornamental Plants. *Plants* **2023**, *12*, 3493. https://doi.org/10.3390/ plants12193493

Received: 16 September 2023 Accepted: 27 September 2023 Published: 7 October 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

function of the AP2/ERF superfamily member IlAP2, which interacts with IlMT2a, in enhancing Cd tolerance [5]. Zhu et al. used transcriptome approaches to study the molecular mechanisms affecting the petal coloration of four varieties of *Rhododendron pulchrum*. The results showed that there were differentially expressed genes among the four different petal samples, including signal transduction-related genes, anthocyanin biosynthesis genes and transcription factors. The development of a red color may be related to a higher expression of *DFR* genes, which promotes the accumulation of anthocyanin [6]. Zhang et al. were involved in regulating plant branching and development to provide candidate genes for improving crop architecture through gene editing or directed breeding [7].
