Cyanobacterial biofertilizers provide soil fertility and productivity gains at varying levels in paddy rice cultivation. The colonization and influences of introduced strains in different soil types with characteristic compositions of native cyanobacteria remain largely unknown. In this work, seven paddy rice soils with the composition of indigenous cyanobacteria described by amplicon sequencing analysis were inoculated with the cyanobacterial biofertilizer. The microbial abundance and the cyanophage concentrations were evaluated under light-dark or continuous dark cycles using quantitative polymerase chain reaction (qPCR) assays. The copies of cyanobacterial-16S rRNA gene markers varied from 5.65 × 10⁶ to 9.22 × 10⁷ g^-1 soil, and their abundance increased significantly in the inoculated soils. The cyanophage concentrations, quantified using the capsid assembly protein gene g20 in the soils tested, ranged from 3.04 × 10⁸ to 9.24× 10⁸ g^-1 soil on 30 days after incubation. There were significant increases in the abundance of the nifH gene copies, about 1.54×10⁵ to 1.35×10⁶ g^-1, in the inoculated soils, albeit with soil type-specific responses. The gene markers of C and N cycling (i.e., cbbL and nifH, respectively), taxonomic markers (of archaea, bacteria, and cyanobacteria), and cyanophage-specific gene copies showed strong and positive correlation with the cyanobacterial biofertilizer inoculation. However, the genes related to nitrification (bacterial and archaeal amoA) and denitrification (nirS, nirK, narG, and nosZ) were clustered together in the uninoculated soils. The rice rhizospheres in three representative paddy soil types, using metatranscriptomics analysis, showed distinctive colonization by cyanobacteria, with several members yet to be described. These results indicate the potential for improving cyanobacterial biofertilizers for their contributions to plant growth and fertility gains in a soil-specific way.

蓝藻生物肥料在水稻种植中不同程度地提高土壤肥力和生产力。引入菌株在具有本地蓝藻特征组成的不同土壤类型中的定植和影响仍然很大程度上未知。在这项工作中，用扩增子测序分析描述的含有本土蓝藻成分的七种水稻土壤接种了蓝藻生物肥料。使用定量聚合酶链反应（qPCR）测定在明暗或连续暗循环下评估微生物丰度和噬藻体浓度。蓝藻16S rRNA基因标记在土壤中的拷贝数从5.65×10 ⁶到9.22×10 ⁷ g ^-1不等，且在接种土壤中其丰度显着增加。培养30天后，使用测试土壤中衣壳组装蛋白基因g20定量的噬藻体浓度范围为3.04×10 ⁸至9.24×10 ⁸ g ^-1土壤。尽管存在土壤类型特异性反应，但在接种的土壤中，nifH基因拷贝的丰度显着增加，约1.54×10 ⁵至1.35×10 ⁶ g ^-1 。 C和N循环的基因标记（分别为cbbL和nifH）、分类标记（古细菌、细菌和蓝藻）以及噬藻体特异性基因拷贝数与蓝藻生物肥料接种呈强正相关。然而，与硝化作用（细菌和古菌amoA）和反硝化作用（nirS、nirK、narG和nosZ ）相关的基因在未接种的土壤中聚集在一起。使用宏转录组学分析，三种代表性水稻土类型中的水稻根际显示出蓝藻的独特定植，其中有几个成员尚未描述。这些结果表明改善蓝藻生物肥料的潜力，因为它们以特定土壤的方式对植物生长和肥力增益做出了贡献。