# Potato Yield and Quality, Soil Chemical Properties and Microbial Community as Affected by Different Potato Rotations in Southern Shanxi Province, China

## TL;DR

Rotating potatoes with maize or soybean improves yield, quality, and soil health while reducing disease in southern Shanxi, China.

## Contribution

This study demonstrates that crop rotation with straw incorporation effectively mitigates soil degradation and disease in potato cultivation.

## Key findings

- Potato rotations with maize or soybean increased tuber yield and quality compared to continuous monoculture.
- Soil organic matter, nutrients, and microbial diversity improved significantly under rotation.
- Rotations reduced pathogenic fungi like Fusarium and were linked to soil pH and nitrogen levels.

## Abstract

Continuous potato monoculture leads to yield decline, soil degradation, and increased soil-borne disease incidence. This study evaluated the potential of crop rotation to mitigate these issues by examining its effects on potato performance, soil chemical properties, and soil microbial communities. A two-year field experiment (2023–2024) in southern Shanxi, China, compared three treatments: continuous potato planting (CK, control), potato rotated with summer maize (with maize straw incorporation, T1), and potato rotated with summer soybean (with soybean straw incorporation, T2). The results demonstrated that both T1 and T2 rotations significantly increased tuber yield by 18.39% and 20.69%, respectively, and improved the potato commodity rate by 19.67% and 10.39%, compared to CK. Rotations also enhanced tuber quality, significantly increasing the content of nitrogen (5.24–28.20%), phosphorus (14.68–34.86%), potassium (23.61–52.42%), crude protein (5.14–28.11%), vitamin C (6.67–20.0%), starch (20.0–28.82%), and dry matter (4.55–12.88%), while reducing sugar content. In addition, the soil quality markedly improved under rotation. The soil organic matter, available phosphorus, available potassium, and total nitrogen increased by 27.77–31.92%, 10.48–12.38%, 4.44–28.42%, and 3.98–16.13%, respectively. Proteobacteria, Actinobacteriota, Acidobacteriota, Chloroflex, Firmicutes, and Myxococcota were the predominant bacterial phyla and Ascomycota, Mortierellomycota, Basidiomycota, and Chytridiomycota were the predominant fungal phyla. Microbial community analysis revealed that T1 rotation affected the Chao1 index and the ACE, measures of the diversity of the soil fungal community, and the rotations altered community structure. The abundance of pathogenic fungi, including Fusarium, Alternaria, and Lectera, was significantly reduced. Redundancy analysis (RDA) revealed that pH and total nitrogen (TN) were the primary factors shaping soil bacterial and fungal community structure. In conclusion, rotating potato with summer maize or soybean, combined with straw incorporation, is an effective strategy for enhancing tuber yield and quality, improving soil fertility, suppressing soil-borne pathogens, and promoting sustainable potato production in southern Shanxi.