Rotational Strip Bean and Celery Intercropping Alters the Microbial Community to Improve Crop Yield and Soil Nutrients

Rotational strip intercropping involves the strategic combination of stubble intercropping and the rotational placement of intercropped strips, which can improve crop yield. Here, we evaluated the effects of rotational strip bean (Phaseolus vulgaris L.) and celery (Apium graveolens L.) intercropping with bed ratios of 1:1 and 2:2 on crop yield, soil microbial community and nutrition. The 1:1 ratio of rotational strip bean and celery intercropping had a higher yield than the 2:2 ratio. The 1:1 rotational strip intercropping markedly improved the nitrate nitrogen and available phosphorus contents of the beans, and the nitrate nitrogen and available potassium contents of the celery. The 2:2 rotational strip intercropping reduced the bacterial α diversity of the beans, and the 1:1 and 2:2 rotational strip intercropping enhanced the fungal α diversity of both the beans and the celery. Both planting patterns also altered the microbial communities found on the bean and celery plants. Microorganisms enriched in the rhizosphere of the bean and celery plants significantly increased the soil nutrient content and yield in the 1:1 rotational strip intercropping, and included the genera Achromobacter, Luteibacter, Stenotrophomonas, Fusarium, Flavobacterium and Preussia in the bean rhizosphere, and Alternaria, Arthrographis and Pluteus, Sphingopyxis and Clostridium_sensu_stricto_1 in the celery rhizosphere.