Effects of Different Organic Fertilizers on Soil Microbial Functional Diversity of Greenhouse Chrysanthemum under Chemical Fertilizers Reduction

Purpose It was investigated the effects of refined organic fertilizer in combination with 20% reduced chemical fertilizer (ROF), bio-organic fertilizer in combination with 20% reduced chemical fertilizer (BOF) and conventional chemical fertilization (CF, 100% chemical fertilizer) on soil microbes, microbial functional diversity, yield and quality of chrysanthemum (Chrysanthemum morifolium Ramat.).Method Based on field experiment, chrysanthemum-‘Youxing’ as test material,BIOLOG ECO micro plate method and dilution plate counting method were used in this study.Results Compared with the CF treatment, the BOF treatment significantly increased the quantity of soil bacterial, actimonyces and the microorganisms population by 53.7%, 85.6% and 70.1% respectively, decreased the quantity of soil fungi by 63.9%, increased Shannon index (H) and McIntash index (U) by 4.8% and 27.0% respectively, promoted the soil microbial metabolic activity and utilization of the carbon source, and enhanced the ornamental characters of chrysanthemum. The ROF treatment decreased the quantity of fungi by 48.4%, increased McIntash index (U) and the utility of carbohydrates by 18.2% and 11.5% respectively. However, compared with the ROF treatment, the BOF treatment significantly increased the quantity of soil bacterial, actimonyces and the microorganism population by 34.1%, 51.3% and 35.0%, and increased the utilization of polymer, phenol and amine by 13.7%, 84.9% and 22.5%, respectively. The principal component analysis (PCA) demonstrated that there was an obvious difference in soil microbial community structure by applying different fertilizer treatments, mainly depended on the utilization of carbohydrates, polymers and carboxylic acids.Conclusion During the full growth stage with 20% chemical fertilizer reduction, application of different organic fertilizers can guarantee the yield of chrysanthemum, among them, the bio-organic fertilizer treatment also improve the soil microbial flora and promote the soil microbial metabolic activity.