Molecular Pathogens, 2025, Vol.16, No.2, 45-52 http://microbescipublisher.com/index.php/mp 49 whether rice is prone to illness. Good bacteria in the soil can help plants enhance their immunity, thereby reducing the chances of occurrence such as rice blast and bacterial blight. The current breeding work can also be done in combination with this aspect. For example, using marker-assisted selection techniques can select varieties that are more suitable for utilizing beneficial soil microorganisms, thereby enhancing disease resistance (Ludwików et al., 2015; Zhang et al., 2022). 6.3 Role of agronomic practices in enhancing resistance Daily planting management will also affect rice disease resistance. Methods such as crop rotation and adding organic fertilizer can improve soil conditions, make rice healthier, and the risk of getting sick is lower. Some disease-resistant genes can also be used through breeding. For example, the Xa4 gene can not only enhance cell walls and improve resistance, but also not affect yield (Hu et al., 2017). In addition, genetic engineering can help. For example, using bacteria-inducible promoters (such as those that control WRKY45) to regulate the expression of disease-resistant genes has been shown in some breeding experiments (Goto et al., 2016). 7 Case Studies of Successful Rice Breeding Programs 7.1 Development of IR64 and its blast resistance improvement IR64 is a high-yield rice variety, and its cultivation is an important breakthrough in rice breeding. This variety not only has high yields, but also has improved its resistance to rice blast disease later. The researchers used molecular methods such as marker-assisted selection and gene stacking to quickly introduce multiple disease-resistant genes into IR64. This allows it to resist a variety of bacteria and has a long-lasting resistance effect (Ashkani et al., 2015; Tao et al., 2021; Anwaar et al., 2024). Through these technologies, we can breed more disease-resistant and stable rice varieties, which is very helpful to food security. 7.2 Breeding programs in southeast asia targeting bacterial leaf blight In Southeast Asia, white leaf blight (BLB) is one of the main diseases affecting rice harvest. In order to deal with it, local breeding projects focus on developing varieties that can resist diseases for a long time, using both traditional breeding methods and molecular technology. In these projects, researchers found several useful disease-resistant genes (R genes) and used them in breeding, which increased the broad-spectrum resistance of rice to BLB (Chukwu et al., 2019; Jiang et al., 2020). The addition of marker-assisted selection and genetic engineering has accelerated the introduction of disease-resistant genes and also reduced the impact of this disease on yield. 7.3 Lessons from large-scale field trials and farmer adoption Large-area field experiments and actual use by farmers are important steps in testing rice breeding results. Experiments can tell us how newly bred varieties perform under different climates and planting conditions. In the land rice breeding project in Brazil, researchers screened out some varieties that were highly resistant to multiple diseases through repeated trials. After the promotion of these varieties, farmers are very enthusiastic about planting because of stable yields and fewer diseases, and the benefits are also improved. A specific example is the Tellahamsa breed. It has high yield and strong adaptability, but it is prone to infection with BB and Blast. Later, the researchers used marker-assisted backcross breeding (MABB) technology to introduce two BB disease-resistant genes (Xa21 and xa13) and two blast disease-resistant genes (Pi54 and Pi1) into Tellahamsa, and bred two new lines: TH-625-159 and TH-625-491 (Jamaloddin et al., 2020; Alves et al., 2021). These two new lines performed well after trials in different regions. They not only had strong disease resistance, but also retained the good yield and quality of the original varieties (Figure 2). This example shows that advanced breeding methods combined with field trials are key to achieving sustainable disease management. 8 Challenges and Future Directions in Rice Disease Resistance Breeding 8.1 Overcoming pathogen evolution and resistance breakdown A major problem with rice disease-resistant breeding is that the bacteria change too quickly. Sometimes, an originally resistant variety will lose its effect in no time. For example, after some new rice blast bacteria appear, the old varieties will no longer work (Singh et al., 2018). To deal with this situation, the researchers thought of
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