Fuente: WIPO "tomato" A Penicillium cyclopium strain capable of degrading crop straw fibers efficiently and application thereof are provided. The provided induces mutagenesis of a Penicillium cyclopium strain MP-03 (2554-2) (CGMCC No. 41542) using a nitrosoguanidine method and obtains a mutant strain ΔMP-03 (455-1) (CGMCC No. 41541) with enhanced ability to degrade corn straw. By optimizing a nitrogen-to-carbon ratio of culture medium, culture time, temperature, and a pH range for high enzymatic activity, the mutant strain 455-1 significantly enhances the degradation of corn straw, and endoglucanase and exoglucanase activities in corn straw compared with the non-mutant strain 2554-2. The provided optimizes the conditions for scale-up culture of the mutant strain 455-1, and develops the organic-coupled cultivation technology that integrates a fermentation suspension of the mutant strain 455-1, corn straw and organic fertilizer, which improves the growth, root development and photosynthetic efficiency of greenhouse vegetable, and resistance to the soil-borne oomycete diseases.