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There are many species of terrestrial Mollusca with rapid reproduction rates, a wide distribution range, and a large population. They are not only an important wildlife resource but also an important component of biodiversity. Previously, basic research has been conducted on the species diversity and distribution of terrestrial Mollusca in some nature reserves in Guizhou and Yunnan. The existing sample data of terrestrial Mollusca in Guizhou and survey results from Guiyang, Libo, and Xishui from July 2019 to December 2020 listed 316 species and subspecies (including 13 undefined species) belonging to two subclasses, four orders, 20 families, and 76 genera in Guizhou Province. From the perspective of species composition, the dominant family is Cyclophoridae, with 16 genera and 71 species; the second most dominant family is Bradybaenidae, with 15 genera and 61 species, followed by Helicinidae and Cochlicopidae with one genera and one species. The dominant species are Kaliella cavicola, Bradybaena similaris, Diplommatina herziana, Diplommatina consularis, Chamalycaeus nanus, and Plectotropis pseudopatula. From the perspective of geographical distribution, terrestrial Mollusca are the most abundant in the central region of Guizhou, with 17 families, 54 genera, and 170 species. The areas with the second greatest abundance of terrestrial Mollusca are the sub-subtropical humid areas in southern Guizhou and the sub-subtropical areas in southwestern Guizhou, with 18 families, 56 genera, and 152 species and 17 families, 57 genera, and 150 species, respectively. There are only 10 families, 18 genera, and 27 species in the eastern area of Guizhou. Similarity analysis of species in different regions of Guizhou Province showed that the species composition of terrestrial Mollusca in the southern area, northern area, and southwestern area of Guizhou is similar, whereas the species composition of terrestrial Mollusca in the eastern area of Guizhou is markedly different from that of other regions. This paper discusses the species and distribution pattern of terrestrial Mollusca in Guizhou Province and their resource characteristics to provide a scientific basis for the protection and rational utilization of terrestrial Mollusca resources and to further enrich the research data of terrestrial Mollusca in China.

Plant--bacteria interactions are known to play important physiological roles in plant growth. Determining the mechanisms behind these interactions has paramount agricultural and ecological importance. Therefore, it is essential to study Plant--bacteria interactions and determine the relevant molecular mechanisms by using model systems. This review summarizes the current knowledge regarding plant--bacteria interactions based on the Arabidopsis thaliana--Bacillus subtilis model system, and highlights future areas for research. Key words: Arabidopsis thaliana, Bacillus subtilis GB03, plant--bacteria interaction. Les interactions plantes--bacteries sont connues pour jouer des rôles physiologiques importants dans la croissance de la plante. L'elucidation des mecanismes qui sous-tendent ces interactions est de premiere importance dans le developpement d'applications agricoles et ecologiques. Par consequent, il est essentiel d'etudier les interactions plantes--bacteries et de mettre au jour les mecanismes moleculaires associes au moyen d'un systeme modele. La presente synthese vise a resumer les connaissances actuelles relatives aux interactions plantes--bacteries sur la base du systeme modele constitue d'Arabidopsis thaliana--Bacillus subtilis, et souligne les voies futures de recherche. [Traduit par la Redaction] Mots-cles: Arabidopsis thaliana, Bacillus subtilis GB03, interaction plante--bacterie., Introduction It is difficult to reconcile the urgent need for increased food production with the need to reduce the use of pesticides and fertilizers in order to protect the ecological [...]

Rhododendron delavayi is a natural shrub with importance in preventing rocky desertification in the karst regions of Bijie city of China. The structure of fungal communities in bulk soil, rhizosphere and roots of R. delavayi at three elevations was analyzed by ITS2 amplicon sequencing. The results showed that the soil pH was highest at 1448 m, while the content of available phosphorus, total nitrogen and total phosphorus was lowest at 1821 m. The Shannon of fungal communities in bulk soil was higher than roots at 1448 m. Ascomycota and Basidiomycota were the most dominant phyla present in bulk soil, rhizosphere and root endophyte. The pH was positively related to Chytridiomycota and Glomeromycota in bulk soil at 1643 m. Ammonium-nitrogen significantly influenced the fungal communities in bulk soil, while the elevations impacted the diversity of fungal communities by affecting available phosphorus content in bulk soil and roots. In summary, elevation significantly affected the diversity and structure of fungal communities by affecting soil pH and nutrient levels, and the fungal communities helped R. delavayi in adaptating to different elevations. [ABSTRACT FROM AUTHOR]

Previous studies have shown that plant–pollinator mutualistic interactions experience highly interannual variation. Given that pollinators often move across multiple plant species, the plant–plant interactions that take place via heterospecific pollen (HP) transfer may also vary temporally, which could have important implications for floral evolution and community assembly. Here, we evaluated the interannual variation in plant–pollinator networks and plant–plant heterospecific pollen transfer (HPT) networks of a subalpine meadow community in Southwest China for three consecutive years. The interactions largely varied among years for both network types. The composition of donor-species HP deposited on the plants varied less than did the visit composition of the pollinators, suggesting that HP could be transferred from identical donor species to recipient species through different shared pollinators among years. The plant species were at more similar positions in the HPT network than they were in the plant–pollinator network across years. Moreover, the more generalized plant species in the plant–pollinator network tended to export their pollen grains and more strongly influence HPT. We evaluated the relatively stable structure of the HPT network compared with the plant–pollinator network, which represents an important step in the integration of plant–pollinator and plant–plant interactions. [ABSTRACT FROM AUTHOR]