This study aimed to investigate the biological characteristics and patterns of different Prunus species as hybrid parents in artificial cross-pollination to improve the success rate of hybrid breeding.

Seven Prunus species were selected for cross-pollination in different combinations. Pollen morphology was observed, and pollen germination rate and stigma receptivity were evaluated at four developmental stages (small bud stage, large bud stage, initial flowering stage, and full flowering stage) using in vitro culture and benzidine-hydrogen peroxide methods. Pollen tube growth and ovary fertilization were examined via fluorescence microscopy. Fruit-setting rates among different hybrid combinations were analyzed for correlations.

The exine ornamentation of all seven pollen types exhibited striate sculpturing, with variations in pollen grain size, number of surface apertures, and exine texture thickness. Both pollen germination rate and stigma receptivity initially increased and then decreased across the four stages, peaking at the initial flowering stage. Pollen tubes began growing 4 h after pollination, with fertilization completed within 96-120 h. A concentrated fruit drop occurred 14-28 d after pollination, and fruit-setting rates stabilized by 35 d. Significant correlations were observed between fruit-setting rate and polar axis length (P<0.05), aperture length, and stigma receptivity (P<0.05), while pollen germination rate showed a significant correlation (P < 0.05).

The optimal period for pollen collection and pollination is the early flowering stage. All seven Prunus taxa examined exhibit either synchronogamy or protogyny. Inter-specific hybridization yields significantly lower fruit-set than intra-specific crosses, suggesting the existence of both pre- and post-zygotic reproductive barriers.

This work aimed to investigate the community structure and species diversity of wild Prunus discoidea in Mufu Mountain, Pingjiang, Hunan Province, so as to provide a theoretical basis for the protection, rational development and utilization of wild cherry germplasm resources.

By using the method of a typical sample plot survey, 27 sample plots were set up to investigate the community structure of the wild Prunus discoidea community in Mufu Mountain, Pingjiang, Hunan Province. The species diversity of the Prunus discoidea community was evaluated based on the Gleason richness index, Simpson dominance index, Shannon diversity index and Pielou evenness index.

The species composition of the Prunus discoidea community in Mufu Mountain of Pingjiang consisted of 38 families, 59 genera and 69 species of vascular plants. The flora was dominated by pantropical plants, followed by north temperate plants. The life-form spectrum was mainly composed of phanerophytes, accounting for 72.46%, followed by geophytes, accounting for 11.59%. The vertical structure was the shrub layer and the herb layer. The ground diameter structure of the community was an “inverted J type”, which is the growing type. The dominant species in the shrub layer of the Prunus discoidea community were Prunus discoidea, Loropetalum chinense and Camellia oleifera, and the dominant species in the herb layer were Nephrolepis cordifolia, Miscanthus floridulus and Cyrtomium fortunei. In terms of the species diversity of the Prunus discoidea community, the Gleason richness index was 5.97 in the shrub layer and 2.26 in the herb layer. The Simpson dominance index was 0.90 in the shrub layer and 0.40 in the herb layer. The Shannon diversity index was 2.94 in the shrub layer and 1.06 in the herb layer. The Pielou evenness index was 0.77 in the shrub layer and 0.38 in the herb layer, and the overall species diversity of the shrub layer was higher than that of the herb layer.

The Prunus discoidea community in Mufu Mountain, Pingjiang, Hunan Province is in the early stage of secondary forest evolution, and the community structure is relatively simple. The species diversity of the herb layer is relatively weak. The Prunus discoidea community belongs to a growing community, in order to maintain stability and expand the growth space of the community. It is necessary to take conservation measures such as pruning surrounding trees.

To study the relationship between the color value and their active substance content and antioxidant capacity.

Using 11 different flowering cheery petals as materials, the color phenotype of the flower was determined by RHSCC and color difference instrument. The contents of total phenols, total flavonoids, anthocyanins and antioxidant capacity of the petals were determined by UV-visible spectrophotometer, and anthocyanin components were analyzed by HPLC.

1) The 11 flowering cherry could be divided into three colors: violet, red purple and purple. The larger the L* value of flowering cherry petals, the lighter the color of the petals; the lower the b* value, and the opposite trend of a*. The value of a* and b* was the main factor affecting L*. There were certain differences between the results and the RHSCC; 2) There were significant differences in the contents of total phenols, total flavonoids and total anthocyanins in 11 flowering cheery petals. The content of total phenol and total flavonoids of Cerasus campanulate ‘Ryukyu-hizakura’ was the highest, which was 19.31 mg·g^-1 and 59.61 mg·g^-1. Cerasus speciosa ‘Yaebeni-ohshima’ had the lowest total phenol content of 9.35 mg·g^-1, and Cerasus ‘Introrsa’ had the lowest total flavonoid content of 12.75 mg·g^-1. The highest anthocyanins content of Cerasus campanulata ‘Kanhizakura-plena’ was found in the darkest color of 2.12 mg·g^-1, while the lightest color of Prunus speciosa ‘Yaebeni-ohshima’ having the lowest content of 0.05 mg·g^-1; 3) Four anthocyanins, including cyanidin, petunidin, peonidin and malyidin were detected in 11 flowering cherry petals, and the types and contents were different. Cyanidin and petunidin were the main anthocyanins in the petals; 4) There were significant differences in antioxidant capacity of 11 flowering cheery petals, and the reducing capacity of iron ion was stronger than DPPH and ABTS radicals. The contents of total phenols and total anthocyanins in petals were positively correlated with the antioxidant capacity indexes.

There were significant differences in color value of 11 flowering cherry petals, total anthocyanin content and different anthocyanin species and contents were the main factors determining the difference in flowering cherry color. The phenolic content would affect the antioxidant capacity of the petals.