Abstract: Aiming at the promotion challenges of high dosage and high cost in the field application of Paenibacillus ottoensis NPDY05-8, straw was proposed for the direct field propagation of this strain to reduce the field application cost and improve the feasibility of its technological popularization. In this study, the broad-spectrum bacteriostatic Paenibacillus ottoensis NPDY05-8 was taken as the research object, and whole-genome sequencing, cellulase gene analysis, morphological observation and cellulose utilization capacity determination were conducted on it. A systematic study on the technological optimization of its field propagation with straw as the sole nutrient source was carried out. Single-factor experiments were performed to investigate the effects of culture temperature, initial pH value, inoculum size and straw content on strain propagation, and the optimal propagation conditions were clarified. The results showed that whole-genome sequencing revealed that strain NPDY05-8 contained four cellulase genes（GH51, GH94, GH56, GH74）, enabling it to reproduce rapidly with straw as the sole nutrient source. The results of single-factor experiments indicated that the optimal propagation conditions were as follows: daily average temperature of 20℃～30℃, initial pH of 6.5～7.0, inoculum size of more than 0.125%（v/v）, and straw content of more than 5.0 g·L⁻¹. Under these conditions, the biomass of the strain could reach more than 10⁷ CFU·mL⁻¹, meeting the requirements of field irrigation application. The research results provide technical support for the large-scale field application of Paenibacillus ottoensis NPDY05-8, and also offer a technical guarantee for the popularization of green prevention and control of maize stalk rot.