RESUMEN
Long-term continuous cropping of facility soils could influence soil properties; however, the differences in soil properties among different continuous cropping years are still not well understood. The objective of this study was to explore the effects of continuous cropping years of tomato on the physical and chemical properties and biological characteristics of facility soil. Conventional analysis, high-throughput sequencing, and other methods were used to examine the soil physicochemical properties, soil microbial community diversity, and enzyme activities in facility soil after continuous tomato cropping for 1-3 years, 5-7 years, and more than 10 years. As the continuous tomato cropping years increased, soil bulk density and pH decreased; soil maximal water holding capacity increased; and organic matter, total nitrogen, and total phosphorus accumulated. As continuous cropping years increased, the total salt and EC value decreased with continuous cropping for 5-7 years and increased from 5-7 years to more than 10 years continuous cropping and showed a trend of secondary soil salinization. There was a significant increase in alkaline phosphatase for 1-3 years to 5-7 years continuous tomato cropping. There were significant differences in fungal community abundance among different cropping years. The Simpson index and Shannon index of fungi showed a trend of increasing first and then decreasing with the extension of continuous cropping years and reached the maximum value at 5 years of continuous cropping. The Chao1 index decreased continuously following the cropping years. As continuous cropping years increased, Streptomyces became the dominant bacteria, and Aspergillus and Pseudaleuria became the dominant fungi. The key factors affected by continuous cropping years were available potassium and available nitrogen based on the redundancy analysis. The results of this study lay the foundation for future research on the influence of continuous cropping years on the health of facility soil.
Asunto(s)
Microbiota , Solanum lycopersicum , Suelo/química , Microbiología del Suelo , Rizosfera , Hongos , NitrógenoRESUMEN
The objective of this study was to explore the microbial diversity and community composition under saline soil and to screen the salt-tolerant microbial flora from salinization habitats. The soil from three different habitats(primary salinization, secondary salinization, and healthy soil) in Hebei Province were sampled. The convention method and high-throughput sequencing technology were used to examine the physicochemical properties and microorganism diversity. The soil chemical properties of the three habitats were significantly different. Compared with those of field soil, the soil OM, AP, AK, TS, and EC values of greenhouse soil and TS and EC values of coastal saline soil were significantly higher. However, other chemical indexes of coastal saline soil were significantly lower. The diversity index and abundance of soil bacteria in greenhouse soil were the highest, followed by those in field soil and coastal saline soil as the lowest. The diversity index and abundance of fungi in two saline habitats were significantly lower than that in field soil. The community structure of saline soil was analyzed at the phylum and genus levels. Chloroflexi and its genera and Ascomycota and its genera, such as Trichocladium and Fusarium, were the dominant microbial groups in saline soil. EC and TS were the main factors affecting microbial diversity and community composition. EC and TS were positively correlated with unclassified_A4b, unclassified_Chloroflexi, unclassified_α-Proteobacteria, Trichocladium, unclassified_Chaetomiaceae, Crassicarpon, Cephaliophora, and Sodiomyces. The results of this study lay the foundation for future research on screening microbial resources needed for saline soil remediation.