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The genus Impatiens exhibits some varied floral features with a dichogamous reproductive system, in which pollination biology plays a key role in speciation and adaptive evolution. China is one of the centers of Impatiens species, including a large number of endemic and sympatric distributions, but there are few data on their pollination biology. Comparative pollination biology of two Chinese endemic and sympatric species, Impatiens corchorifolia and I. cyathiflora, were investigated, including flowering phenology, floral features, pollinators, behavior of pollinators, and as well as breeding systems. The results were as follows: (1) Morphology of spur was varied in two species, which played a key role in different floral syndromes. The spurs in I. corchorifolia and I. cyathiflora could produced a similar nectar sugar content, (45.48 ± 2.28)% and (46.12 ± 1.48)%, respectively. They could share two pollinators, Apis cerana and Vespa. However, the short spur in I. corchorifolia produced less amount of (4.57 ± 1.43) μL nectar while the long spur in I. cyathiflora yielded more nectar content of (10.15 ± 3.28) μL. And then, the latter also could be pollinated by the other insects including one species of Macroglossum and two species of Bombus. (2) The behavior of the common pollinators shared in I. corchorifolia and I. cyathiflora were obviously distinguished by their staggered flower visits and differential sizes of flower channels for visitors with inconsistent positions of pollens carried. (3) Breeding system experiments showed that species possessed obvious hybridization barriers and obvious cross-pollination. Thus, significant differences in spur morphology lead to distinct pollination syndrome differentiation and different pollinator behavior. Both species prefer cross-pollination to self-fertiliation, which greatly depend on the effective pollinators. Reproductive isolation could be maintained by different flower visiting behavior of shared pollinators, differences in floral morphology, and heterozygous discordance. It provides new evidence for a better understanding the relationships between pollination syndrome, pollinators behavior, and cross-breeding stystem in Impatiens.

This paper takes Dongzhaigang National Nature Reserve and 1 km peripheral zone as the study area, selects Sentinel-2 remote sensing image data from 2017—2021, decodes landscape types using human-computer interaction, calculates landscape pattern index, and then compares and analyzes the landscape pattern changes inside and outside the reserve during the 5-year period and its main driving forces. The results show that (1) within the protected area, the mangrove wetland area shows an increasing trend, the woodland area decreases, and the cultured water area decreases significantly; the protected area has better landscape connectivity and lower fragmentation, among which mangrove is the dominant landscape. (2) In the peripheral zone, the area of mangrove wetlands has increased, the area of woodland has decreased, the area of cultured water surface and construction area have decreased, but the area of cultivated land has increased; compared with the protected area, the landscape fragmentation is higher and the connectivity and integrity are poor. (3) Mangrove ecological conservation and restoration activities were the main drivers of significant changes in the landscape pattern of the protected area, while human activities such as farming and construction were the main factors that changed the landscape pattern of the peripheral zone. The results of the study are of reference value for optimizing the conservation management of the reserve and strengthening the control of human activities in the peripheral zone.

Rosa rugosa is a deciduous shrub belonging to Rosa L. in Rosaceae. It has a high ornamental value and commercial value, but its single color limits the development and utilization of rose and its application in landscape architecture. In order to explore the coloring substances of three different varieties of roses, ‘Rosa rugosa × Rosa sertata’, ‘Rosa Crimson Glory’ and ‘Rosa alba’, this study used ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) to detect the types and contents of flavonoids in petals. The KEGG database was used to enrich the differential metabolites, screen out the key metabolites, and analyze the correlation with the phenotypic value of flower color. The results were as follows: (1) A total of 58 metabolites were detected in the petals of three different color rose varieties, of which only one anthocyanin was cyanidin-3-O-glucoside, accounting for 30.45%. (2) K-means clustering analysis showed that a total of 12 key metabolites were annotated to the KEGG metabolic pathway. Among them, pinocembrin and myricetin were the main substances that determined the red color of ‘Rosa rugosa × Rosa sertata’ and ‘Rosa Crimson Glory’, and eriodictyol, luteolin and kaempferol were the main substances that determined the white color of ‘Rosa alba’. In conclusion, this study can provide a theoretical basis for the breeding of roses with specific colors and promote the application of roses in landscaping.