Tartary buckwheat are very popular as an important functional food material and its cultivation is very widespread in our whole world, but there obviously lack works in the researches of genetic breeding for agricultural and medicinal utilization. The aim of this study is to obtain good germplasm resources for agricultural and medicinal use of tartary buckwheat (Fagopyrum tataricum) by inducing the tetraploid plants. Four cultivars of F. tataricum, that is, Qianwei 2#, Jinku 2#, Chuanqiao 1#, and Liuqiao 1# were selected to experiment. The tips of seedlings with two true leaves were treated by 0.25% (w/v) colchicine solution for 48, 72, and 96 h, respectively. The chromosome number of treated plants was determined by metaphase chromosome counting of root tip cells and PMCs (pollen mother cells) meiosis observation. Tetraploid induction successfully occurred in all three treatments with an efficiency ranging from 12.13 to 54.55%. The chromosome number of the diploid plants was 2n = 2x = 16, and that of the induced tetraploid plants was 2n = 4x = 32. The typical morphological and physiological qualities were compared between the control diploid and corresponding induced tetraploid plants. Results showed that the induced tetraploid plants had obviously larger leaves, flowers, and seeds. Moreover, the content of seed protein and flavonoid were also increased in the tetraploid plants. The pollen diameter and capsule size of diploid plants were significantly smaller than those of tetraploid plants. Fagopyrum tataricum can be effectively induced into tetraploids by colchicines. The tetraploid induction can produce valuable germplasm resources for breeding and is a practicable breeding way in F. tataricum.

The present study aim is to elucidate the effect and influencing mechanism of land use change on soil C, N, and P stoichiometric characteristics, soil enzyme activity and the microbial community in the karst ecosystem of southwest China. The three typical successive evolution land use types of original forest land, slope farmland and shrub-grassland were selected as the study objects in the present study. Additionally, the change in the laws and relationships of soil, the C, N, and P stoichiometric characteristics, the five soil enzyme activities of urease, sucrose, alkaline phosphatase, amylase and protease, and soil microbial community during the land use evolution process were studied. Results showed that (1) during the evolution process of the three land use types, soil C, N, and P stoichiometric characteristics, enzyme activities and microbial PLFAs (phospholipid fatty acids) varied significantly or extremely significantly; (2) in the three land use types studied, there were significant or extremely significant correlations between soil C, N, and P stoichiometric characteristics, enzyme activities and microbial PLFAs; (3) the ecological project of returning farmland to woodland had remarkable ecological effects on increasing soil C and N sink, repairing soil microbial community and improving soil quality; (4) artificial afforestation should be used as the most important and preferential measure for karst vegetation restoration and reconstruction. The present results not only provided scientific bases for land sustainable utilization, vegetation restoration and reconstruction, but also had important value in reducing the release and increasing the sequestration of soil C and N in karst ecosystems of Southwest China.

Three typical rocky desertification regions of South China Karst were selected as experiment sites. Ninety plots, each with an area of 20 m × 20 m, representative of the five degrees of rocky desertification (nil, potential, slight, moderate and severe) were established, and plant diversity and soil physicalchemical properties were surveyed and analyzed. The vegetation of rocky desertification ecosystems proved to be very simple with an extremely low species richness index. With increased degree of rocky desertification, there are remarkable changes in plant diversity: species number declines; the ratio of dominant species importance value is higher; species composition becomes more disorder. There are significant differences in plant diversity indices among different degrees of rocky desertification. On the large scale, evenness and dominance indices of plant diversity increase and the Shannon-Wiener index decreases along the increased gradient of desertification. There were also significant differences in soil physical-chemical properties among the five degrees of desertification. Both physical and chemical properties do not always degenerate with increased degree of rocky desertification. Instead, properties initially degenerate and then improve. And there was a remarkable correlation between soil physicalchemical properties and plant diversity. All these offer bases to clarify the evolution law and formation mechanism of plant diversity and soil physical-chemical properties in karst rocky desertification ecosystem, and have extremely important value in the rehabilitation of the karst rocky desertification ecosystem.

The Libo-Huanjiang heritage site serves as a natural refuge for many animals and plants, boasting an extremely rich plant species. There are a total of 1207 species of vascular plants in the heritage site, belonging to 624 genera and 179 families. Of these plants, 27 species are listed in the IUCN Red List, 156 species are listed in the China Species Red List, 142 species are listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), and 154 species are listed in the National Key Protected Plants List of China. In light of the biodiversity conservation value of the heritage site, corresponding protection countermeasures were proposed to provide technical support and facilitate auxiliary decision-making for the biodiversity conservation and management of the heritage site. This study has important significance for protecting, managing, and developing biodiversity in World Natural Heritage sites.

Soil microorganisms play a critical regulatory role in various ecosystem functions, making them essential for maintaining ecosystem stability. Plant functional diversity influences soil physicochemical properties and shapes the structure and function of soil microbial communities. However, the response patterns of soil microorganisms to karst rocky desertification (KRD) succession remain poorly understood, particularly the relationship between microbial community dynamics and aboveground plant functional diversity. Here, the present study focuses on four typical succession KRD stages in a representative karst area of southwest China. By analyzing the diversity and community composition of soil microorganisms (bacteria and fungi), measuring soil physicochemical properties, and assessing aboveground plant functional diversity, the study aims to clarify the response patterns of soil microbial communities to KRD and their relationships with plant functional diversity in the KRD ecosystem of southwest China. The following main results and conclusions were obtained: (1) The composition of soil microbial communities and diversity varied significantly across different rocky desertification degrees. Functional diversity of aboveground plants also exhibited significant differences across varying rocky desertification degrees. (2) Both taxonomic composition and diversity indices of soil microorganisms (bacteria and fungi) showed significant ( p < 0.05) or highly significant ( p < 0.01) correlations with soil physicochemical properties and plant functional diversity across the four rocky desertification degrees. (3) During the karst rocky desertification succession, soil bacterial diversity was directly influenced by plant functional diversity and soil physicochemical properties. While, soil fungal diversity exhibited direct regulation by soil physicochemical properties and indirect effects from plant functional diversity mediated through soil properties. During the rocky desertification succession process, there are very complex interactions present among plants, soils, and microorganisms. Elucidating these relationships is of great significance for vegetation restoration and rocky desertification control in karst regions.