Molecular Pathogens, 2025, Vol.16, No.3, 100-110 http://microbescipublisher.com/index.php/mp 101 sorghum rotation mode in alleviating pest and disease pressure is of great practical significance. This study aims to explore the impact of sorghum's pest and disease resistance mechanism on soil ecology, control of major pests and diseases, and application results in different regions in the rotation system, and propose a generalizable agricultural management strategy, in order to provide theoretical support and practical path for green and sustainable sorghum planting. 2 Ecological Relationship Between Sorghum and Pests and Diseases 2.1 Physiological mechanism of sorghum's resistance to pests and diseases As an ancient and important food and feed crop, sorghum has formed a unique mechanism of resistance to pests and diseases in the long-term process of natural selection and artificial breeding. In terms of chemical defense, sorghum is rich in cyanogenic compounds, such as dhurrin, which rapidly decompose and release hydrogen cyanide when the plant is mechanically damaged or fed by insects, which is toxic to insects (Krothapalli et al., 2013). Studies have found that sorghum varieties containing high concentrations of dhurrin have stronger repellency and resistance to pests such as aphids and stem borers, and this chemical defense can play an early protective role in the seedling stage (Chen et al., 2024). In addition, tannins and polyphenols in sorghum tissues also have antibacterial activity, which can interfere with the cell wall synthesis and toxin production of pathogenic fungi, thereby fighting fungal diseases such as anthracnose and leaf spot (Little et al., 2023). At the physiological response level, disease-resistant sorghum varieties can quickly stimulate the activity of antioxidant enzymes such as peroxidase (POD) and superoxide dismutase (SOD) after pathogen invasion, scavenge reactive oxygen free radicals, and protect cell structures (Chen et al., 2024). Some sorghum strains also have high jasmonic acid (JA) and salicylic acid (SA) contents, which can induce systemic acquired resistance and enhance the resistance of the whole plant to multiple pathogens (Carrión et al., 2019). It is worth noting that sorghum has a well-developed root system and rich secretions, which can form a mutually beneficial symbiotic relationship with soil microorganisms, indirectly enhancing its defense against soil-borne diseases. For example, phenolic acid compounds secreted by the rhizosphere have been shown to promote the growth of antagonistic microbial communities and enhance the rhizosphere ecological barrier function (Sun et al., 2023). These physiological bases provide theoretical support for sorghum to act as an "antagonistic crop" in the rotation system. 2.2 Interaction between crop species and biological factors Pathogenic microorganisms and pest species are significantly different from those of crops such as legumes and crucifers, so they are often given the role of "non-host crops" in rotation systems. This "non-host barrier" mechanism can break the biological chain of specific pests and pathogens and reduce their continued occurrence in the field (Okosun et al., 2021). For example, in the sorghum-soybean rotation system, the introduction of soybeans significantly reduced the field incidence of sorghum stem base rot, and sorghum, as a non-host of non-leguminous cyst nematodes, also weakened its population base, achieving two-way suppression of diseases and insects (Sun et al., 2024). It is worth noting that there are also obvious differences between the root activities and secretions of sorghum and other crops, which in turn exert selective pressure on the soil micro-ecosystem. Studies have found that symbiotic microorganisms such as actinomycetes and arbuscular mycorrhizal fungi are enriched in the rhizosphere of sorghum, which helps to inhibit the spread of soil-borne pathogens; while legumes tend to attract nitrogen-fixing bacteria, thereby enhancing soil nutrient cycling and ecological function stability. This complementarity of rhizosphere metabolic niches has become an important basis for sorghum to regulate the balance of pathogens and antagonistic microorganisms in diversified rotations. In order to more intuitively understand the ecological interaction mechanism of sorghum in the rotation system, Zhou et al. (2023) systematically summarized the relationship between sorghum and pests and diseases. The
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