微生物菌剂对连作半夏生长及根际微生物群落结构的影响

Effects of microbial inoculants on the growth and rhizosphere microbial community structure of Pinellia ternata in continuous cropping

摘要:

背景 连作障碍严重影响半夏的产量，成为制约半夏产业发展的重要因素。目的 探究利用微生物菌剂调控连作半夏土壤根际微生物群落，来缓解半夏连作障碍，为消除半夏连作障碍提供参考。方法 以连作一年的半夏及半夏根际土壤为研究对象，常规施肥(CK，有机肥750 kg/hm²)为对照，设置枯草芽孢杆菌(Bacillus subtilis)菌剂KC (12 kg/hm²)、哈茨木霉(Trichoderma harzianum)菌剂HC (12 kg/hm²)、解淀粉芽孢杆菌(Bacillus amyloliquefaciens)菌剂JD (2.25 kg/hm²)、复合菌剂ZH (7.50 kg/hm²) 4种处理，对不同菌剂处理下不同时期的半夏生长及土壤微生物群落进行研究。结果 与CK相比，复合菌剂ZH处理效果最好，在珠芽成熟期的株高、叶长和叶柄粗分别提高了6.51%、2.61%和18.78%，产量提高了77.32%，水分、灰分、浸出物、水溶性蛋白和生物碱含量分别增加3.76%、16.48%、14.11%、36.45%和18.37%。高通量测序分析表明，复合菌剂ZH处理改变了土壤细菌和真菌群落及优势菌的相对丰度，在门水平上，与CK相比，变形菌门(Pseudomonadota)、拟杆菌门(Bacteroidota)和放线菌门(Actinomycetota)的相对丰度增加，酸杆菌门(Acidobacteriota)、子囊菌门(Ascomycota)相对丰度降低；属水平上，鞘氨醇单胞菌属(Sphingomonas)、硝化螺旋菌属(Nitrospira)的相对丰度增加，镰刀菌属(Fusarium)、寡营养丛孢霉属(Plectosphaerella)相对丰度降低。关联分析发现，产量和总生物碱与酸杆菌门未分类属(unclassified genera of Acidobacteriota)呈显著负相关，水分、浸出物和水溶性蛋白与糖菌属(Saccharibacteria)呈显著正相关，水分与Plectosphaerella和青霉属(Penicillium)呈显著正相关。结论 复合菌剂ZH处理可以调节根际微生物群落的结构和多样性，增加有益菌的数量，减少病原菌的存在，从而促进半夏的生长发育，具有促进生长与微生态调控的双重优势，为半夏绿色高效种植提供了科学依据。

Abstract:

Background Continuous cropping obstacles seriously affect the yield of Pinellia ternata and become a key factor restricting the development of the P. ternata industry.Objective We explored the use of microbial inoculants to regulate the rhizosphere microbial community in the continuous cropping soil of P. ternata to alleviate the continuous cropping obstacle, aiming to provide reference for eliminating the continuous cropping obstacle of P. ternata.Methods P. ternata and its rhizosphere soil after continuous cropping for one year were taken as the research objects. With conventional fertilization (CK, organic fertilizer 750 kg/hm²) as the control, four treatments of Bacillus subtilis (Bacillus subtilis, KC, 12 kg/hm²), Trichoderma harzianum (Trichoderma harzianum, HC, 12 kg/hm²), Bacillus amyloliquefaciens (Bacillus amyloliquefaciens, JD, 2.25 kg/hm²), and compound microbial inoculant (ZH, 7.50 kg/hm²) were designed to study the growth of P. ternata and soil microbial communities at different growth stages.Results Compared with CK, ZH treatment had the best effect, increasing the plant height, leaf length, and petiole diameter by 6.51%, 2.61%, and 18.78%, respectively. This treatment increased the yield by 77.32%. Moreover, it increased the content of water, ash, extract, water-soluble protein, and alkaloids by 3.76%, 16.48%, 14.11%, 36.45%, and 18.37%, respectively. High-throughput sequencing showed that ZH treatment changed the relative abundance of soil bacterial and fungal communities and dominant bacteria. At the phylum level, compared with CK, ZH treatment increased the relative abundance of Pseudomonadota, Bacteroidota, and Actinomycetota, while decreasing the relative abundance of Acidobacteriota and Ascomycota. At the genus level, ZH treatment increased the relative abundance of Sphingomonas and Nitrospira, while decreasing the relative abundance of Fusarium and Plectosphaerella. Correlation analysis showed that the yield and total alkaloids had significantly negative correlations with unclassified genera of Acidobacteriota. Water, extract, and water-soluble protein demonstrated significantly positive correlations with Saccharibacteria, and water showcased significantly positive correlations with Plectosphaerella and Penicillium.Conclusion ZH treatment can regulate the structure and diversity of the rhizosphere microbial community, increasing beneficial microorganisms and reducing pathogens, thereby promoting the growth and development of P. ternata. It has the dual effects of promoting plant growth and regulating the microbial ecosystem. These findings provide a scientific basis for the eco-friendly and efficient cultivation of P. ternata.