Molecular Pathogens, 2025, Vol.16, No.4, 171-181 http://microbescipublisher.com/index.php/mp 172 directions and prospects. Through the systematic elaboration of the above content, it is expected to provide useful reference for future research and production practice of rice bacterial resistant stripe disease breeding. 2 Overview of Bacterial Stripe Spot Disease in Rice 2.1 Classification and biological characteristics of pathogenic bacteria Bacterial strabular disease of rice is caused by infection with Xanthomonas oryzae pv. oryzicola (Xoc). It is a Gram-negative bacteria that specializes in infecting rice. This pathogen belongs to the genus Xanthomona of the order Xanthomonadales and Xanthomonadaaceae, and is closely related to the rice pathogenic variant (X. oryzae pv. oryzae, Xoo) that causes white leaf blight. The two have similarities in genetic and pathogenicity, but the invasion site and pathogenic properties are different: Xoc mainly infects the parenchymal tissue of rice leaves, causing narrow stripe lesions, while Xoo expands through leaf veins, forming large-area leaf dysfunction symptoms. Xoc bacteria are short rod-shaped, monopolar flagella, and can swim in the host surface and in the leaflet water membrane to invade plant tissue from water pores or wounds (Wan et al., 2021). Its genome encodes a series of secretion systems and effector molecules, among which the type III secretion system (T3SS) and its secreted transcriptional activator-like effector protein (TALE) play a key role in the pathogenesis process. Typical strains of Xoc (such as the Chinese Guangxi strain GX01) usually carry more than 20 TALE family genes. After these effector proteins enter the nucleus of rice cells, they can bind to the effector binding elements on the promoter of the host gene, activate or inhibit the expression of specific genes, thereby interfering with the plant immune response or promoting nutrient supply (Wang et al., 2024). 2.2 Epidemiological characteristics and environmental influencing factors The distribution of rice bacterial stripe disease in the world is mainly concentrated in warm and humid rice-farming areas. It is currently known that the disease is widely present in rice areas in East Asia and Southeast Asia, including southern China, Southeast Asian countries and parts of South Asia, and has also been found in some West African countries (Hutin et al., 2024). The prevalence of diseases is closely related to environmental conditions: high temperature and high humidity are conducive to the survival and spread of pathogenic bacteria in the rice field environment. When the daily average temperature is between 25 ℃ and 30 ℃ and the relative humidity of the air continues to be above 80%, the prevalence of bacterial strabular disease is easily induced. Especially in the late rice season or rainy season, if the fields accumulate water and leaves are wet for a long time, the pathogenic bacteria will spread rapidly in the rice population through wind and rain, leading to epidemic outbreaks. In addition, management measures in the rice growth environment will also affect the occurrence of diseases: excessive application of nitrogen fertilizer will increase the sensitivity of the plants and make the lesions expand faster; high-density planting and unreasonable crop rotation in rice fields also increase the chance of pathogenic bacteria transmission and residues. Pathogens can survive and overwinter on sick bodies and seeds, becoming the initial source of infection for the next season. Seed-carrying bacteria is an important way for the long-distance transmission of diseases. The transportation of infected rice seeds may spread pathogens to new areas, so strengthening phytosanitation is crucial to prevent the disease from spreading across regions (Han et al., 2024). 2.3 Comprehensive impact on rice growth, yield and quality Bacterial stripe spots mainly infect rice leaves, forming brown to yellowish-brown stripe spots. In severe cases, the lesions are continuous, resulting in large leaves that fade prematurely and yellow. The direct effect of the disease on rice growth is manifested as a decrease in photosynthesis area and a decrease in the accumulation of assimilated products. After the onset of the leaves, the photosynthetic efficiency decreased significantly, the growth potential of the plant weakened, the tillering rate decreased, and the maturation period was delayed (Figure 1) (Liu et al., 2022). A large number of studies and field surveys have shown that the incidence of bacterial strabular disease is negatively correlated with rice yield: field-induced disease varieties generally reduce production by more than 10% in epidemic years, moderate epidemics can reduce production by 20% to 30%, and the yield reduction rate even exceeds 50% in severe outbreaks. The disease not only causes a decrease in the fruit rate and a decrease in the weight of 1 000 grains, but also affects the quality of rice. Because lesions affect leaf
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