Establishment and Application of Multiplex PCR System for Blast Resistance Genes Pi-ta and Pi-b in Rice

Abstract

Rice blast is one of the important diseases in major rice producing areas in China. The main blast resistance genes Pi-ta and Pi-b showed wide and durable resistance spectrum in many rice growing areas. In this study, two sets of multiple PCR system primed by functional markers were established to identify Pi-ta and Pi-b, using 22 rice varieties with known alleles on both Pi-ta and Pi-b loci. The PCR system I could detect the resistance alleles on Pi-ta and Pi-b loci, while the PCR system II could detect the susceptible alleles simultaneously. The effectiveness of the two PCR systems was validated in 336 japonica breeding lines. The result was highly consistent with that of molecular detection using conventional single marker. Therefore, the two multiple PCR systems developed are stable, reliable and time-saving, and can serve as a rapid and efficient method to identify Pi-ta and Pi-b genes in bulky screening and marker-assistant selection in rice aiming at blast resistance breeding.

Research progress on the breeding of japonica super rice varieties in Jiangsu Province, China

“…Combined with conventional breeding techniques, we quickly and successfully tracked and pyramided two important genes and accurately obtained a homozygous target gene for several varieties including Nanjing 46, Nanjing 5055, Nanjing 9108, and others with strong resistance to stripe disease, good edibility qualities, and high yield (Wang et al 2008a, b, c, d;Yao et al 2010). In recent years, we successfully used molecular markers for Pita and Pib to assist the selection of panicle neck blast resistance with positive results (Yao et al 2015). As long as the single plant contained Pita and Pib markers, roughly 75% of its neck blast resistance was rated among 0 and 2.…”