关键词: 三七, 有机覆盖, 土壤养分, 微生物多样性

Abstract: The effects of organic mulching on soil nutrient change, microbial richness and diversity of Panax notoginseng were studied in order to provide theoretical basis and support cultivation techniques for P. notoginseng mulching planting. A completely random block plot experiment was performed to cover the soil surface of P. notoginseng seeds with organic mulch. It was conducted with five treatments including Artemisia annua mulching(HHH),  Tagetes erecta L. mulching(WSJ), Fagopyrum dibotrys mulching(JQM), pine needle  mulching(SZ), and no mulching (CK). Soil samples were collected after 10 months of growth. Soil nutrient content and microbial diversity were determined by chemical analysis and high-throughput sequencing. The results showed that: ① the organic matters of treatment HHH and SZ were significantly higher than that of CK, the total nitrogen and hydrolytic nitrogen content of treatment HHH was significantly higher than that of CK, and the available phosphorus and potassium contents of treatment SZ were significantly higher than that of CK after 10 months. ② There was a strong positive correlation between total nitrogen content and hydrolytic nitrogen. ③ 27 phylum and 64 classes and 131 orders and 263 families and 444 genus were obtained by sequencing the 16S rDNA of bacteria, Proteobacteria, Actinobacteria, and Bacteroidetes were the main dominant phylum. Acidibacter, Gennmtimonas, and Flavobacterium were the main dominant genus. The bacterial richness and diversity of treatment WSJ, JQM, and SZ were higher than those of CK, while those of treatment HHH were lower than those of CK. ④ There were differences in community structure and diversity of soil fungi. 12 phylums, 40 classes, 115 orders, 246 families, 510 genera were obtained by sequencing the ITS region of fungi. Ascomycota, Basidiomycota, Zygomycota were the main dominant phylum. Conocybe, Fusarium, Mortierella and Trichoderma were the main dominant genus. The richness and diversity of fungal community in mulching treatment were lower than that in non-mulching treatment. A. annua and pine needle mulching provided nutrients of soil，and organic mulching improved the ability of P. notoginseng to fight against pathogenic bacteria, and mulching pine needle had some effect on reducing the occurrence of P. notoginseng root rot and solving the obstacle of P. notoginseng continuous cropping.

Key words: P. notoginseng (Burk.) F. H. Chen, organic mulch, soil nutrient, microbial diversity