半夏间作生姜对产量、土壤酶活性和根际微生物群落结构的影响

Pinellia ternata-Zingiber officinale intercropping affects crop yields, soil enzyme activities, and rhizosphere microbial community structure

摘要:

【背景】 半夏的连作障碍已成为制约半夏产量与品质的重要影响因素。轮、间作耕作体系可有效地消减作物的连作障碍。【目的】 探究利用半夏间作生姜的种植模式来缓解半夏连作障碍，为消除半夏土壤连作障碍提供参考。【方法】 以半夏间作生姜种植模式中的半夏和生姜根际土壤，以及单作半夏和生姜的根际土壤为研究对象，对不同种植方式下产量、土壤酶活性、土壤微生物群落特征及其之间的相互关系进行研究。【结果】 当土地当量比(land equivalent ratio, LER)>1时，表明间作体系较2种作物单作有优势，半夏间作生姜LER为1.85，说明半夏和生姜间作优势明显。间作半夏(BSB)较单作半夏(BX)处理的土壤过氧化氢酶、脲酶、蔗糖酶酶活性分别显著增加了11.01%、25.05%、4.96%。间作生姜(BSS)较单作生姜(SJ)处理则增加了5.02%、72.68%、19.75%。半夏间作生姜种植模式提高了半夏的根际微生物种类、物种丰富度和物种多样性。在真菌门水平，相较于单作，间作下子囊菌门(Ascomycota)的相对丰度降低，被孢霉门(Mortierellomycota)的相对丰度升高；在细菌门水平，相较于单作，间作下放线菌门(Actinomycetota)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidota)的相对丰度升高，绿弯菌门(Chloroflexota)、酸杆菌门(Acidobacteriota)、芽单胞菌门(Gemmatimonadota)的相对丰度降低；在真菌属水平，间作处理减少了镰刀菌属(Fusarium)的相对丰度；在细菌属水平，节杆菌属(Arthrobacter)、鞘氨醇单胞菌属(Sphingomonas)、芽孢杆菌属(Bacillus)的相对丰度均增加。Spearman相关性分析表明：被孢霉门的相对丰度与产量、土壤蔗糖酶呈显著正相关，子囊菌门的相对丰度与产量呈显著负相关；放线菌门、厚壁菌门(Firmicutes)的相对丰度与土壤过氧化氢酶、脲酶呈正相关；绿弯菌门、酸杆菌门、芽单胞菌门、浮霉菌门(Planctomycetota)、蓝藻(Cyanobacteria)的相对丰度与脲酶、蔗糖酶呈负相关。【结论】 半夏间作生姜改变了土壤细菌群落结构，提高土壤酶活性和有益菌物种丰度，实现了半夏增产，可作为改善半夏连作障碍、提高产量的有效措施。

关键词:半夏;细菌和真菌群落;高通量测序;酶活性

Abstract:

[Background] The continuous cropping obstacle has become a major factor limiting the yield and quality of Pinellia ternata. Rotation and intercropping can alleviate the continuous cropping obstacle. [Objective] To explore the P. ternata-Zingiber officinale intercropping pattern on continuous cropping obstacle and provide reference for eliminating the obstacle in the production of P. ternata. [Methods] The rhizosphere soil samples of P. ternata and Z. officinale in the intercropping pattern and those of the two crops in monoculture were collected. The crop yields, soil enzyme activities, soil microbial community characteristics, and their relationships under different planting patterns were explored. [Results] The land equivalent ratio (LER)>1 indicates that intercropping outperforms monoculture. In this study, the LER of intercropping was 1.85, indicating that intercropping had obvious advantages. The activities of catalase, urease, and sucrase in the soil of P. ternata in intercropping increased by 11.01%, 25.05% and 4.96%, respectively, compared with those in the soil planted with P. ternata alone and by 5.02%, 72.68% and 19.75%, respectively, compared with those in the soil planted with Z. officinale alone. Intercropping increased the microbial species, richness, and diversity in the rhizosphere soil of P. ternata. In terms of soil fungal phyla, intercropping decreased the relative abundance of Ascomycota and increased the relative abundance of Mortierellomycota compared with monoculture. In terms of soil bacterial phyla, intercropping increased the relative abundance of Actinomycetota, Proteobacteria and Bacteroidetes, and decreased the relative abundance of Chloroflexota, Acidobacteriota and Gemmatimonadota, compared with monoculture. At the fungal genus level, intercropping reduced the relative abundance of Fusarium. At the bacterial genus level, intercropping increased the relative abundance of Arthrobacter, Sphingomonas and Bacillus. Spearman correlation analysis showed that the relative abundance of Mortierellomycota was positively correlated with the yield and soil sucrase activity, while the relative abundance of Ascomycota was negatively correlated with the yield. The relative abundance of Actinomycetota and Firmicutes was positively correlated with soil catalase and urease activities. The relative abundance of Chloroflexota, Acidobacteriota, Gemmatimonadota, Planctomycetota and Cyanobacteria was negatively correlated with soil urease and sucrase activities. [Conclusion] P. ternata-Z. officinale intercropping can change the soil bacterial community structure and improve soil enzyme activities and beneficial microorganism abundance, serving as an effective measure to alleviate the continuous cropping obstacle and increase the yield of P. ternata.

Key words:Pinellia ternata;bacterial and fungal communities;high-throughput sequencing;enzyme activity