Keywords
BLB
broad-spectrum resistance
differential lines
Xoo races
Abstract
Bacterial leaf blight (BLB) is a major rice disease in the Philippines, making the identification of BLB-resistant varieties and their underlying mechanisms critical for breeding. This study evaluated twenty gamma-ray-induced advanced (M₁₂) mutant rice lines derived from the traditional variety Gal-ong, alongside susceptible checks and IRBB differential lines that possess known Xa genes and with defined reactions to different Xanthomonas oryzae pv. oryzae (Xoo) races. All the materials were screened against ten Xoo strains representing nine major Philippine races prevalent in local rice-growing regions across the country. This revealed that some of the mutants (GXB-229, GXB-SB-9, GXB-51, GXB-61, GXB-225-1 and GXB-1) had a wide spectrum of resistance against the different Xoo races, with broad-spectrum resistance indices (BSRI ≥ 0.8) comparable to those of the broad-spectrum resistant checks. In trying to estimate the causal genes of the mutants, a discrepancy was observed between the reaction profiles of the mutants with those of the resistant IRBB checks, indicating possible gain-of-function or novel genetic mechanisms in the Gal-ong mutants. This is supported by the sequence analysis (BLASTN) of 32 Xa genes in Gal-ong and GXB207 genomes, which showed that 15 truncated Xa genes in Gal-ong were partially to fully restored in the mutant in terms of homology length to the full-length query sequence as a random effect of gamma irradiation. Overall, this study identified new BLB-resistant materials that, when further subjected to genetic analysis, could become invaluable sources of novel BLB resistance genes for rice breeding.
References
Ahloowalia, B., & Maluszynski, M. (2001). Induced mutations—A new paradigm in plant breeding. Euphytica, 118, 167–173.
Alfonso, A. A., Avellanoza, E. S., Miranda, R. T., Espejo, E. O., & Garcia, N. S. (2015). Production and characterization of gamma ray‑induced rice mutants with broad‑spectrum resistance to the bacterial blight pathogen Xanthomonas oryzae pv. oryzae. Philippine Journal of Crop Science, 40(3), 1‑9. ([UKDR UPLB][1].
Ashwini, S., Prashanthi, S. K., Vidyashankar, D., Hegde, Y. R., Krishnaraju, P. U., Muttappagol, M., Krishnanand, I., & Abinash. (2024). Insights into the virulence profiles and molecular diversity of Xanthomonas oryzae pv. oryzae isolates are associated with bacterial blight of rice in major districts of Karnataka, India. Physiological and Molecular Plant Pathology, 133, 102338.
Baloch, A. W., Soomro, A. M., Javed, M. A., Bughio, H. U. R., Alam, S. M., Bughio, M. S., Mohammed, T., & Mastoi, N. U. N. (2003). Induction of salt tolerance in rice through mutation breeding. Asian Journal of Plant Sciences (Pakistan), 2(3).
Chen, S. (2002). Functional analysis of the rice bacterial blight resistance gene Xa25. Molecular Plant-Microbe Interactions, 15(6), 713–720.
Cheng, X., Zhou, G., Chen, W., Tan, L., Long, Q., Cui, F., Tan, L., Zou, G., & Tan, Y. (2024). Current status of molecular rice breeding for durable and broad-spectrum resistance to major diseases and insect pests. Theoretical and Applied Genetics, 137(10), 219.
Dossa, G. S., Sparks, A., Vera Cruz, C., & Oliva, R. (2015). Decision tools for bacterial blight resistance gene deployment in rice-based agricultural ecosystems. Frontiers in Plant Science, 6, 305.
International Rice Research Institute. (2013). Standard evaluation system for rice, 5th edition. International Rice Research Institute.
International Rice Research Institute. (2014). Statistical Tool for Agricultural Research (STAR) (Version 2.0.1) [Computer software]. Biometrics and Breeding Informatics Division, IRRI.
Jiang, N., Yan, J., Liang, Y., Shi, Y., He, Z., Wu, Y., Zeng, Q., Liu, X., & Peng, J. (2020). Resistance Genes and their Interactions with bacterial blight/leaf streak pathogens (Xanthomonas oryzae) in Rice (Oryza sativa L.)—an Updated Review. Rice 13, 3 (2020).
Kauffman, H.E., Reddy, A.P.K., Hsieh, S.P.Y. & Merca, S.D. (1973). An improved technique for evaluating resistance of rice varieties to Xanthomonas oryzae. Plant Disease Reporter. 57, 537-541.
Kou, Y., & Wang, S. (2010). Broad-spectrum and durability: understanding of quantitative disease resistance. Current opinion in plant biology, 13(2), 181-185.
Lee, S. W., Choi, G. J., Kim, J. C., Kim, H. T., Choi, Y. H., & Cho, K. Y. (2003). Loss-of-function and gain-of-function rice mutants from gamma-ray mutagenesis. Plant Pathology Journal, 19(6), 301–304.
Li, L., MO, X., LI, T., ZHANG, L., & DONG, H. (2020). Effector XopN of Xanthomonas oryzae pv. oryzae plays a virulent role in rice varieties harboring OsSWEET11 homologs. Chinese Journal of Rice Science, 34(4), 368.
Liu, Z., Zhu, Y., Shi, H., Qiu, J., Ding, X., & Kou, Y. (2021). Recent progress in rice broad-spectrum disease resistance. International journal of molecular sciences, 22(21), 11658.
Lo, K. L., Chen, Y. N., Chiang, M. Y., Chen, M. C., Panibe, J. P., Chiu, C. C., Liu, L. W., Chen, L. J., Chen, C. W., Li, W. H., & Wang, C. S. (2022). Two genomic regions of a sodium azide induced rice mutant confer broad-spectrum and durable resistance to blast disease. Rice, 15(1), 2.
Lu, J., Wang, C., Zeng, D., Li, J., Shi, X., Shi, Y., & Zhou, Y. (2021). Genome‑wide association study dissects resistance loci against bacterial blight in a diverse rice panel from the 3000 Rice Genomes Project. Rice, 14, 22.
Mew, T. W., Vera Cruz, C. M., & Medalla, E. S. (1992). Changes in race frequency of Xanthomonas oryzae pv. oryzae in response to rice cultivars planted in the Philippines.
Mundt, C. C. (2014). Durable resistance: a key to sustainable management of pathogens and pests. Infection, Genetics and Evolution, 27, 446-455.
Oliva, R., Ji, C., Atienza-Grande, G., Huguet-Tapia, J. C., Perez-Quintero, A., Li, T., Eom, J. S., Li, C. Nguyen, H. Liu, B., Auguy, F., Sciallano, C. Luu, V. T., Dossa G. S., Cunnac, S., Schmidt, S. M., Slamet-Loedin, I. H., Vera Cruz, C., Szurek, B., …, & Yang, B. (2019). Broad-spectrum resistance to bacterial blight in rice using genome editing. Nature biotechnology, 37(11), 1344-1350.
Raza, A., Razzaq, A., Mehmood, S. S., Zou, X., Zhang, X., Lv, Y., & Xu, J. (2019). Impact of climate change on crops adaptation and strategies to tackle its outcome: A review. Plants, 8(2), 34.
Song, W. Y., Wang, G. L., Chen, L. L., Kim, H. S., Pi, L. Y., Holsten, T., Gardner, J., Wang, B., Zhai, W. X., Zhu, L. H., Fauquet, C. & Ronald, P. (1995). A receptor kinase-like protein encoded by the rice disease resistance gene, Xa21. Science, 270(5243), 1804-1806.
Vera Cruz, C. M., Bai, J., Oña, I., Leung, H., Nelson, R. J., Mew, T. W., & Leach, J. E. (2000). Predicting durability of a disease resistance gene based on an assessment of the fitness loss and epidemiological consequences of an avirulence gene mutation. Proceedings of the National Academy of Sciences, 97(25), 13,500–13,505.
Yang, B., Sugio, A., & White, F. F. (2006). Os8N3 is a host disease susceptibility gene for bacterial blight of rice. Proceedings of the National Academy of Sciences, 103(27), 10503–10508.
Zhong, Q., Xu, Y., & Rao, Y. (2024). Mechanism of rice resistance to bacterial leaf blight via phytohormones. Plants, 13(18), 2541.