Flowering characteristics and breeding system of the rare plant Rosa anemoniflora

[Objective] The study aims to examine the breeding system, pollination characteristics, and endangered mechanism of Rosa anemoniflora, and provide theoretical basis for the protection and breeding of the rare and endangered plants. [Methods] Pollen viability was measured by in vitro culture germination method. Stigma receptivity was measured by benzidine hydrogen peroxide method. Pollen morphology was observed by scanning electron microscope. Flower characteristics, flowering dynamics, and visiting insects were manually recorded and observed. [Results] (1) The pollen vitality of R. anemoniflora was the highest on the fourth day of flowering, and the best period of stigma receptivity was the third day. (2) The single flowering period of R. anemoniflora was 5-7 days, and the population flowering period was about 25 days. The hybridization index (OCI) was 4. The breeding system was heterozygous with partially selfcompatible, and outbreeding requires pollinators. (3) R. anemoniflora had a single pollinator, with Apis cerana and Bombus sp. being the main pollinators. [Conclusion] The breeding mechanism of R. anemoniflora was heterozygous, partially self-compatible, and pollinated by insects. The single pollinating insect and the susceptibility of pollination behavior to weather conditions and human interference were important reasons for the endangerment of R. anemoniflora. Releasing effective insects during the flowering period and reducing human damage were important measures for the conservation of R. anemoniflora.