Climate change is an important driver of biodiversity patterns and species distributions, understanding how organisms respond to climate change will shed light on the conservation of endangered species. In this study, we modeled the distributional dynamics of a critically endangered montane shrub Lonicera oblata in response to climate change under different periods by building a comprehensive habitat suitability model considering the effects of soil and vegetation conditions. Our results indicated that the current suitable habitats for L. oblata are located scarcely in North China. Historical modeling indicated that L. oblata achieved its maximum potential distribution in the last interglacial period which covered southwest China, while its distribution area decreased for almost 50% during the last glacial maximum. It further contracted during the middle Holocene to a distribution resembling the current pattern. Future modeling showed that the suitable habitats of L. oblata contracted dramatically, and populations were fragmentedly distributed in these areas. As a whole, the distribution of L. oblata showed significant migration northward in latitude but no altitudinal shift. Several mountains in North China may provide future stable climatic areas for L. oblata, particularly, the intersections between the Taihang and Yan mountains. Our study strongly suggested that the endangered montane shrub L. oblata are sensitive to climate change, and the results provide new insights into the conservation of it and other endangered species.
Background: Plants in cliff habitats may evolve specific reproductive strategies to cope with harsh environments, and unraveling these reproductive characteristics can improve our understanding of survival strategies and lithophyte evolution. This understanding is especially important for efforts to protect rare and endemic plants. Here, we investigated the reproductive biology of Lonicera oblata, an endangered lithophytic shrub that is scattered in highly fragmented and isolated cliff habitats of the Taihang and Yan mountains in North China. Results: Flowers of L. oblata are herkogamous and protandrous, characteristics that can prevent autogamy at the single-flower level, and insects are necessary for pollination. The outcrossing index, pollen/ovule ratio, and the results of hand pollination were measured and all revealed a mixed mating system for L. oblata, that combines cross-fertilization and partial self-fertilization. The floral traits of L. oblata of zygomorphic and brightly yellowish corolla, heavy fragrance, and rich nectar, suggest an entomophilous pollination system. Sweat bees were observed as the most effective pollinators but their visiting frequencies were not high. Pollen limitation may limit the reproductive success of L. oblata. Conclusions: We determined the reproductive characteristics of L. oblata, a critically endangered species endemic to cliffs in North China, providing insight into its endangerment and suggesting conservation strategies. L. oblata has highly pollinator-dependent self-fertilization as part of a mixed mating system. Floral features such as low-flowering synchrony, asynchronous anthers dehiscence, and high duration of stigma receptivity, improve pollination efficiency in the case of low pollinator service. Our work provides reference information to understand the survival strategies and conservation of L. oblata and other lithophytes.
11 July 2020 in Journal of Systematics and Evolution
The cosmopolitan family Solanaceae, which originated and first diversified in South America, is economically important. The tribe Hyoscyameae is one of the three clades in Solanaceae that occurs outside of the New World; Hyoscyameae genera are distributed mainly in Europe and Asia, and have centers of species diversity in the Qinghai-Tibet Plateau and adjacent regions. Although many phylogenetic studies have focused on Solanaceae, the phylogenetic relationships within the tribe Hyoscyameae and its biogeographic history remain obscure. In this study, we reconstructed the phylogeny of Hyoscyameae based on whole chloroplast genome data, and estimated lineage divergence times according to the newly reported fruit fossil from the Eocene Patagonia, Physalis infinemundi, the earliest known fossil of Solanaceae. We reconstructed a robust phylogeny of Hyoscyameae that reveals the berry fruit-type Atropa is sister to the six capsule-bearing genera (Hyoscyameae sensu stricto), Atropanthe is sister to the clade (Scopolia, Physochlaina, Przewalskia), and together they are sister to the robustly supported Anisodus–Hyoscyamus clade. The stem age of Hyoscyameae was inferred to be in the Eocene (47.11 Ma, 95% HPD: 36.75–57.86 Ma), and the crown ages of Hyoscyameae sensu stricto were estimated as the early Miocene (22.52 Ma, 95% HPD: 15.19–30.53 Ma), which shows a close correlation with the rapid uplift of the Qinghai-Tibet Plateau at the Paleogene/Neogene boundary. Our results provide insights into the phylogenetic relationships and the history of the biogeographic diversification of the tribe Hyoscyameae, as well as plant diversification on the Qinghai-Tibet Plateau.
Physochlaina is an important perennial herbaceous genus with significant medicinal value, while the phylogeny of Physochlaina and tribe Hyoscyameae is not well resolved yet. In this study, we report the complete chloroplast genome sequences of Ph. physaloides, its complete chloroplast genome is 156,413 bp in length, which is a typical quadripartite structure that includes a large single-copy region of 86,659 bp, a small single-copy region of 18,012 bp, and its GC content was 37.7%. A total of 132 genes were identified, including 87 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Furthermore, a phylogenetic tree of the tribe Hyoscyameae was constructed based the complete chloroplast genome sequence, and a new topology of the tribe was obtained. This study provides valuable genetic information for the conservation and utilization of Ph. physaloides and also provide the potential for better understanding of the phylogeny of Hyoscyameae and Solanaceae.
Species in the genus Botrychium are tiny herbaceous plants with simple morphology that are widely distributed in the northern hemisphere. The phylogenetic relationship intra the genus is not well resolved, different species/populations from North America, Europe, and Asia demonstrate a paraphyletic relationship, including Botrychium lunaria. In this study, we reported the first complete chloroplast genome sequence of B. lunaria from Chinese population. It is 138,558 bp in length, and composed with a typical quadripartite structure. The overall GC content is 44.40%. In total, 129 genes were annotated, including 84 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. A maximum-likelihood tree of primitive fern lineage based on complete chloroplast genome sequence data was constructed. The phylogenetic analysis indicated that Botrychium is closely related to other basal fern lineages, such as Helminthostachys, Ophioglossum, and Mankyua. Furthermore, the genomic data generated in this study will provide helpful information for the conservation of B. lunaria in Beijing, China.