Abstract:

The mechanisms underlying rhizosphere environment differences between substrate culture and soil culture remain unclear in the major cut rose production areas of Yunnan, and precise water and fertilizer management lacks scientific support. This study investigated the effects of different cultivation systems on rhizosphere nutrient status and microbial community structures. Using the cut rose cultivar ‘Fenhong Xueshan’ as the experimental material, a systematic comparison was conducted under identical greenhouse conditions. High-throughput sequencing was employed to analyze rhizosphere microbial diversity, and the concentrations of 14 available nutrients were simultaneously determined. The results showed significant divergence in rhizosphere microbial diversity, species distribution, and nutrient contents between the two cultivation modes. Compared with soil cultivation, substrate cultivation increased the numbers of fungal and bacterial OTUs by 27.03% and 28.88%, respectively, with a 9.75% increase in total species count. Analysis of the Feature, Ace, Chao1, Simpson, Shannon, and PD whole tree indices for fungi and bacteria revealed that substrate cultivation increased these values by 27.03% and 27.03%, 30.74% and 28.37%, 30.65% and 26.52%, 13.58% and 0%, 24.12% and 3.38%, and 20.11% and 35.49%, respectively, compared to soil cultivation. Substrate cultivation significantly enhanced rhizosphere microbial populations and promoted the proliferation of functional growth-promoting microbes, including Burkholderiaceae, Rozellomycota, Proteobacteria, Bacteroidetes, and Acidobacteria, while effectively suppressing pathogenic fungi. Analysis of 14 primary available nutrients revealed that soil cultivation favored the accumulation of available phosphorus (P), sulfur (S), iron (Fe), and boron (B), whereas substrate cultivation promoted the accumulation of exchangeable sodium (Na), available magnesium (Mg), and manganese (Mn). Regarding production performance, substrate cultivation significantly increased the number of effective flower shoots per plant (each season 4-6 flower shoots vs. 2-4 shoots in soil), shortened the flowering cycle by 8 days, and exhibited stronger plant growth vigor. In conclusion, substrate cultivation optimizes the rhizosphere microbial structure, increases the abundance of beneficial microbes, and facilitates precise nutrient supply, making it more suitable for the high and stable yield of cut roses. These findings provide a scientific basis for cultivation mode selection, rhizosphere regulation, and precise fertigation management. Future research may focus on multi-cultivar validation and the application of functional microbial communities.

Key words: cultivation modes, cut rose, substrate cultivation, soil cultivation, rhizosphere, nutrient content, microbial diversity