Floral Structure and Breeding Systems of Manglietia conifera Dandy (Magnoliaceae)

Jian Hao,Qingbin Jiang,Hongyan Jia,Khongsak Pinyopusarerk,Antoine Kalinganire,Liqin Pan,Qilong Pan

doi:10.3390/f10090756

Abstract

Manglietia conifera Dandy is a fast-growing tree species that has been introduced to China from Vietnam, which has great potential for commercial planting. However, plantation development is hindered by a lack of seed material, due to low natural seed-set in locally grown trees. Thus, we investigated the morphological characteristics of male and female flower organs, and conducted controlled pollination to understand the breeding systems of the species. The individual flower of M. conifera is bisexual, and the stamen group is polymerized at the base of the receptacle. Pollen is symmetrically distributed on both sides. Controlled pollination suggests that apomixis does not occur in M. conifera. Results from the flower structure, pollen–ovule ratio, outcrossing index, and controlled pollination indicated that the breeding system in M. conifera was outcrossing (partially self-compatible, pollinators required), and self-incompatibility occurred in a later stage of embryonic development. Moreover, the self-incompatibility phenomenon was revealed by the abnormal germination of pollen on the stigma. This paper provides a basis for controlled pollination programs of M. conifera.

Highlights

Manglietia conifera Dandy (Magnoliaceae), formerly known as M. glauca, is an evergreen broad-leaved tree species distributed naturally in northern Vietnam (Figure 1)
The species was first introduced to China in the 1960s and, to date, 110,000 hectares of plantations have been established in the tropical and subtropical regions in the southern provinces of Guangdong, Guangxi, Fujian and Hainan (Figure 1) [2]
Under suitable site conditions [3], the average diameter at breast height can reach 3 cm per annum, which is fast-growing for a high-quality timber species in southern China [4]

Summary

Introduction

Manglietia conifera Dandy (Magnoliaceae), formerly known as M. glauca, is an evergreen broad-leaved tree species distributed naturally in northern Vietnam (Figure 1). It is fast-growing, predominantly with a straight single bole, and has good natural pruning, making it a popular plantation species for wood production in the northern provinces of Vietnam [1]. Manglietia conifera trees growing in China flower annually with moderate intensity, but fruit-set is extremely low and totally absent in some years [5]. This poor fruit-set and low seed yield seriously hamper the expansion of plantation development in China [4,6]. The main flowering period is from early March to mid-May [9]

Methods

Results

Discussion

Conclusion