Subjects: Biology >> Botany >> Applied botany submitted time 2024-03-26 Cooperative journals: 《广西植物》
Abstract： Since the establishment of Anna in 1930, the taxonomic revisions of this genus have been infrequent. Early publications and revisions of Anna were based on specimens collected by foreign missionaries, which led to problems such as brief or inaccurate descriptions of traits and unclear species definition. When researching publication history, comparing morphology and investigating type locality of Anna ophiorrhizoides (Hemsl.) B. L. Burtt & R. A. Davidson and A. rubidiflora S. Z. He, F. Wen & Y. G. Wei, we found that Didymocarpus cavaleriei H. Lév. published by H. Léveillé in 1911 and Anna rubidiflora are actually the same species, and Didymocarpus cavaleriei was treated as a synonym of Anna ophiorrhizoides. After comparing the morphological characteristics of multiple populations of A. ophiorrhizoides and A. rubidiflora, it was found that the difference in their morphological characteristics lies in the corolla. It is not appropriate to use differences in corolla color as boundaries for the classificatory units of species. Taking into account the morphological characteristics and geographical distribution characteristics, it is proposed to treat Anna rubidiflora as a variety of Anna ophiorrhizoides. According to the regulations and suggestions in the 2018 International Code of Nomenclature for Algae, Fungi, and Plants (Shenzhen Code), we propose a new combination and a name at new rank——Anna ophiorrhizoides (Hemsl.) B. L. Burtt & R. A. Davidson var. cavaleriei（H.Lév.）X. X. Bai & F. Wen, and treat Anna rubidiflora as the synonym of the new combination.
Subjects: Biology >> Botany >> Applied botany submitted time 2023-12-24 Cooperative journals: 《广西植物》
Abstract： To provide researh data for the phylogenetic evolution, classification and identification of plants in sect. Tuberculata of Camellia genus, 10 species of the section, leaf epidermal micromorphology and pollen morphology were observed by light microscope and scanning electron microscopy (SEM) and based on pollen features and leaf epidermal features to clustered separately. The results were as follows: (1) 10 species have no significant difference in morphology and size, the pollen shape is prolate, subspheroidal or oblatesphere; the outline of pollen in polar view is trilete rounded or trilete regular teiangular; the outline in equatorial view is oblong, P/E rangs from 0.85 to 1.16; tricolporate aperature. The exine sculpture is different significantly, the featuee have coarsely warty, foveolate reticulate or rugulate with beadedmun and is important classification value for sect. Tuberculata. (2) The cluster analysis of the measurement index showed that when the euclidean distance is 4.5, the 10 species are divided into 4 groups, and some of the classification results are the same as the macroscopic morphological classification. (3) The leaf epidermal cells of 10 species are irregular or straight, with great morphological differences among species. There are gland in the upper and lower epidermis of C. zengii, C. rhytidophylla and C. rubimuricata; cyclic type stomata are only distributed in the lower epidermis; three shape of anticlinal wall pattern shape have sinuolate, sinuous, repand and sinuate. In addition, the cell size and stomatal features (size and density) of leaf epidermis micromorphology were significantly different between species. This study shows that pollen morphology and leaf epidermal micromorphology are diverse in the sect. Tuberculata, which could be used as the basis for distinguishing some closely related species in the sect. Tuberculata.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-03-18 Cooperative journals: 《广西植物》
Abstract： In-depth exploration of the species abundance distribution (SAD) pattern of plant communities under different terrains in the subtropical karst area can reveal the mechanism of formation of the SAD of the community under different terrains, thereby enriching the theory of plant community construction in this area. In this paper, the arbor layer and shrub layer of plant communities under four typical landforms of ridge, trough, saddle and depression in Maolan karst area of Guizhou Province were used as the objects. The empirical cumulative distribution function(ECDF) was used to characterize the SAD, at the same time, the Wilcoxon rank sum test was used to analyze the differences in species abundance between different terrains. Then different ecological models were used for fitting, and Kolmogorov-Smirnov (K-S) test and Akaike Information Criterion (AIC) were used to detect model acceptance and goodness of fit. The results were as follows: (1) There were differences in the number of individuals and species in plant communities under different terranes, the number of individuals in saddles was the most, the number of species in depressions was the most, and the number of individuals and species in ridges was the least. (2) There were significant differences among shrub layers, between ridge and saddle, between ridge and depression, between saddle and trough valley, and between saddle and depression, while there were no significant differences in the SAD of arbor layers in plant communities under different terrains. (3) The SAD of the arbor layer under different terrains was well accepted by the neutral model. The ridge fits best, but all terrains were poorly accepted by ecological models, only the ridge and saddle passed through the two niche models, and the goodness of fit was not as good as that of the neutral model. The shrub layer was also well accepted by the neutral model with the best fit of the saddle, but it was poorly accepted by the niche model, and only the depression passed the broken stick model. Overall, the arbor layer was more acceptable to the two ecological models than the shrub layer, probably because the SAD of the arbor layer had more obvious imprints of ecological processes. However, the difference in the goodness of fit of the shrub layer under different terrains is greater, which may be related to the more drastic changes of the shrub layer species to the environment. Consequently, different terrains lead to different ecological processes of community construction, and the SAD pattern gradually adapts to the terrain.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-03-18 Cooperative journals: 《广西植物》
Abstract： Camellia kweichowensis is a rare 5-locular capsule-bearing representative species of the section Camellia with biological importance and economic value. This study explored the reasons for its endangered status and effective ways to conserve and utilize resources. In this study, by combining the sample investigation and actual measurement methods, the analysis of population age structure and survivability, we studied the quantitative characteristics of population structure dynamics and future development trend. The results were as follows: (1) The primary vegetation of C. kweichowensis had typical characteristics of subtropical humid evergreen broad-leaved forests. While the mixed evergreen and deciduous broad-leaved forest accounted for the main stand, the coniferous broad-leaved mixed forest of Pinus armandii + Betula luminifera + Liquidambar formosana + Nyssa sinensis + Camellia sp. + Eurya sp. + Schima sp. was common. (2) The growth population of C. kweichowensis dominated the growth structure. The points were mainly concentrated in the small and medium tree stages, and the sum of the proportion constituted 73.02% of the overall population. Deevey-Ⅱ type characteristic of the population survival curve was obvious, the life expectancy of C. kweichowensis was the maximum at the seedling stage. The change trend of mortality and the vanishing curves of the same plot were approximately the same. The quantitative dynamic analysis indicated that the three plots had abundant seedling pools, but were sensitive to the disturbance outside the habitat. The probability of surviving to Ⅶ age-class dropped significantly to 36.17%. On the whole, the population structure showed the characteristics of “growth in the early stage and decline in the late stage of Ⅳ age-class”. (3) The time-series forecast analysis indicated that after the growth period of 2-, 4-, 6-, 8-, and 10-diameter scales, the C. kweichowensis population dynamics tilted toward the succession of middle trees (Ⅴ-Ⅶ age-class), big trees (Ⅷ-Ⅹ age-class), and aged trees (Ⅺ-ⅩⅢ age-class). In conclusion, due to the limited habitat resources and space, intraspecific and interspecific competition intensifies, which reduces the survival rate of population seedlings and the number of young, and increased the mortality of adult plants caused by human predatory logging. As a result, the population renewal and diffusion are hindered, the distribution area is narrow, and the species tend to be endangered.
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