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Bacteria play determining roles in forest soil environment and contribute to essential functions in the cycling of nitrogen (N) and phosphorus (P). Understanding the effects of different fertilizer applications, especially successive fertilization, on soil properties and bacterial community could reveal the impacts of fertilization on forest soil ecology and shed light on the nutrient cycling in forest system. This study aimed to evaluate the impacts of successive mineral N (NH4NO3) and P (NaH2PO4) fertilization at different rates, alone or together, on soil bacterial biomass and communities at 0–5, 5–10, and 10–20 cm. Compared with the control, N fertilization decreased soil pH, but P alone or with N fertilization had negligibly negative impacts on soil pH. Different mineral fertilizer applications, alone or together, showed no significant effects on soil organic matter contents, relative to the control treatment. Bacterial biomass remained stable to different fertilizations but decreased with sampling depths. Sole N or P fertilization, rather than combined fertilizations, significantly changed soil bacterial community structures. Our results demonstrated that mineral N or P fertilization alone significantly affected bacterial community structures rather than biomass in the plantation soils. Key points: • Impacts of successive mineral fertilization on soil bacteria were determined. • Mineral fertilization showed negligible impacts on bacterial biomass. • N additions stimulated Chloroflexi relative abundances. • Mineral N or P fertilization significantly altered bacterial community structure. [ABSTRACT FROM AUTHOR]

The effect of the light quality on 2-acetyl-1-pyrroline (2AP) during the grain filling period in fragrant rice has rarely been investigated. A pot experiment was carried out with two fragrant rice varieties, Xiangyaxiangzhan and Yuxiangyouzhan, grown under three light treatments, 100% red light (L1), 100% blue light (L2), and compound light (L3), during the grain filling period, and natural light was taken as the control (CK). The yield, quality, and fragrance were investigated. The results showed that light quality treatments significantly decreased the 2AP content in mature grains by 16.67–32.82% but improved the grain yield by 2.70–21.41% compared to CK. The regulation effects of light quality treatments on grain yield and 2AP are linked to yield-related traits, biomass accumulation, antioxidant physiology, and 2AP formation-related physiology. Additionally, light quality treatments decreased the chalky rice percentage and chalkiness, and increased the length-to-width ratio. Overall, light quality treatments during the grain filling period had a positive effect on the grain yield but not on fragrance in fragrant rice. [ABSTRACT FROM AUTHOR]