Molecular Pathogens, 2025, Vol.16, No.4, 171-181 http://microbescipublisher.com/index.php/mp 173 function, the supply of assimilates during the grouting period is insufficient, the diseased plants are often poor in strength, the grain thinness rate increases, and the enrichment decreases. The rice yield and the whole-sum rice rate of diseased particles will also decrease, and the rice quality will be worse. In addition, bacterial strabular disease infection sometimes causes dark brown spots on the surface of the chaff, affecting the appearance quality of commercial rice (Li et al., 2012). In some rice areas with severe disease, farmers have to harvest in advance in order to reduce losses, resulting in a further decline in rice quality. Figure 1 A model describing how AvrRxo1 targets and degrades PDX1 to inhibit vitamin B6 biosynthesis, leading to a decreased ABA level and stomatal reopening in rice (Adopted from Liu et al., 2022) 3 The Scientific Basis of Rice Disease-Resistant Breeding 3.1 Discovery and functional analysis of disease-resistant genes The cultivation of rice antibacterial disease varieties depends on the acquisition and utilization of genetic resistance genes. For a long time, a large number of studies have been dedicated to discovering and identifying the genetic resources of rice that are resistant to white leaf blight (BB) and resistant to barbed spot disease (BLS). In the rice-white leaf blight interaction system, more than 40 disease-resistant genes have been identified and officially named (Xa1 to Xa46, etc.), of which at least 15 genes have been successfully cloned and resolved. The latest research progress shows that the number of anti-white leaf blight genes is still increasing. By 2023, there have been more than Xa47 and other reported, totaling about 49, with wide resistance spectrum and diverse mechanisms of action (Islam et al., 2024). These genes include dominant disease-resistant genes (R genes), such as the classic Xa21 (coding the receptor kinase protein) and Xa7 (coding the disease-resistant trigger factor protein), as well as recessive disease-resistant genes (such as xa5, xa13, etc., which are usually deficient mutations in sensory genes) (Cao et al., 2018). In contrast, rice has fewer genetic resistance genes to bacterial strabular disease. There are few main-effect anti-stripe genes in cultivated rice, and the early resistances were mostly quantitative trait sites (QTLs) or recessive genes in wild rice. For example, the recessive genes bls1 and bls2 from common wild rice O. rufipogon were shown to confer some resistance to plaque disease, where bls2 showed resistance to multiple Xoc strains (Tannidi et al., 2024). The bls2 gene was first initially localized on the 6th chromosome by Chinese researchers through genetic analysis of wild rice hybrid offspring. 3.2 Disease-resistant genetic mechanism and regulatory network Rice's resistance to bacterial diseases reflects the typical "gene to gene" interaction law, and the genetic mechanism behind it involves a multi-level regulatory network of the plant's innate immune system. At the molecular level, rice recognizes pathogens and stimulates defense through two types of immune receptors: one is the pattern recognition receptor (PRR) on the cell membrane, which can sense pathogen-related molecular patterns to trigger primary immunity (PTI); the other is the disease-resistant protein (mainly NLR proteins) in the cell,
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