Can the anatomy of abnormal flowers elucidate relationships of the androecial members in the ginger (Zingiberaceae)?

Abstract

Background: Interpretation of the floral structure of Zingiberaceae has long concentrated on the relationships of the androecial members. It suggested that labellum is composed of two structures rather than three or five, and glands are interpreted either as gynoecial part or as androecial members. Methods: Serial sections were used to observe the vasculature of normal and two-staminate flowers in Alpinia intermedia 'shengzhen'. Floral diagrams were drawn to interpret the morphological category of the floral organs and the relationships of the androecial members. Androecial vascular bundles were associated with carpellary dorsal bundles (CDBs) and parietal bundles (PBs) in a Zingiberales phylogeny setting using ancestral state reconstruction. Results: Anatomical observations demonstrate that the fertile stamen(s) incorporate parietal bundles both in normal and two-staminate flowers. The three appendages represent the three members of the outer whorl of the androecium, while the labellum represents the inner whorl of the androecium in the two-staminate flower. Reconstruction of the origin of the vascular system in the androecium suggests that the outer whorl of androecium receives its vascular supply from the CDBs, and the inner whorl of androecium receives from the PBs in both the basal banana group and the more derived ginger clade. Conclusions: The present study adds to a growing body of literature suggesting that the anatomy of abnormal flowers may not provide enough evidence for elucidating the relationships of the androecial members, and help us to better understand how the vascular system is constructed during the androecial petaloidy evolution.

Asymmetric expression patterns of B‐ and C‐class MADS‐box genes correspond to the asymmetrically specified androecial identities of Canna indica

“…In Zingiberales, abnormal flowers provide material evidence to study the homeosis through comparative anatomical analyses. Compared with organs in other whorls, androecial members show a much wider variation in abnormal flowers, which conforms to the androecial modifications seen in this order (Rao 1963; Maas 1977; Song et al 2003; Li et al 2020). In this research, comparisons between the abnormal flowers and the normal flowers clearly indicated homologies between the androecial members.…”

Correlation between Inflorescence Architecture and Floral Asymmetry—Evidence from Aberrant Flowers in Canna L. (Cannaceae)

“…Song et al [ 41 ] described six types of abnormal flowers in Alpinia ; these abnormalities include flowers with 2 fertile stamens, 1.5 stamens, 1 stamen, single stamen with only one theca (½ stamen), and fertile stamen completely absent as well as the occurrence of twin flowers forming mirror images. Li et al [ 42 ] recently reported two-staminate aberrant flowers in a cultivar A. intermedia ‘shengzhen’. These aberrant flowers share with one another alterations in the form of the androecial members that indicate common deviations from a canalized developmental pathway.…”

A Study on Petal Morphological and Physiological Characteristics of Styrax japonicus during the Flowering Period

“…Controlling the flowering time and understanding the physiological mechanism of the induction of flowers are essential to the tourism, research, and flower industries [1]. In recent years, many researchers have studied the flowering process, including flower morphological structure, nutrients, mineral elements, enzymes, and relevant genes in flowers, so as to reveal the biological characteristics and regulate the flowering period of different plants [2][3][4][5]. Based on the study of flower morphology in the genus Capsella, Neuffer and Paetsch [6] specifically disclosed the petal size, pollen number, stigma length, and so on in Capsella grandiflora, C. rubella, and C. bursa-pastoris.…”