Improving blast resistance of the rice restorer line, Hui 316, by introducing Pi9 or Pi2 with marker-assisted selection

Abstract

Introducing resistance (R) genes into a susceptible rice cultivar is an effective strategy to achieve broad-spectrum and durable disease resistance. During the breeding process, marker-assisted selection (MAS) provides an efficient approach for direct screening of the progeny containing the R gene in a population. In this study, we designed an optimized polymerase chain reaction marker, Pi9/2, targeting the same polymorphic region of our previously developed Pi9-Pro and demonstrated that Pi9/2 is more specific than Pi9-Pro for the blast resistance genes Pi9 and Pi2 in MAS. With the assistance of Pi9/2, Pi9 and Pi2, from donor lines 75-1-127 and C101A51, respectively, were separately introgressed into the strong rice restorer line, Hui 316, by backcrossing. The two improved representative Hui 316 lines, Hui 316-Pi9 and Hui 316-Pi2, displayed similar agronomic traits to Hui 316. Inoculation tests for blast resistance revealed that Hui 316-Pi9 and Hui 316-Pi2 showed markedly enhanced resistance to blast fungi compared with Hui 316. Investigation of agronomic traits for yield and rice quality indicated that the hybrid combinations from Hui 316-Pi9 or Hui 316-Pi2 crossed with male sterility lines were similar to those derived from Hui 316. Therefore, introgression of Pi9 or Pi2 into with Hui 316 could improve its resistance to blast with little influence on its restoring ability, which will facilitate the application of Hui 316 in rice production. These results also indicate that the optimized marker, Pi9/2, is effective in introducing Pi9 or Pi2 by MAS to improve blast resistance of rice cultivars. ARTICLE HISTORY ÃStatistically significant with P-value <0.05.

Disease resistance of improved MR220 lines against Pyricularia oryzae Cavara and their preliminary agronomic performance

“…Several studies have shown that MAS can efficiently monitor the introgression of blast resistance genes both into the recipient plants and improved varieties. For example, the Pi9/Pi92 gene was introgressed into the rice restorer line Hui 316 by Tian et al (2019). In the present study, we demonstrate the application of MAB in breeding to improve the blast resistance of an elite Malaysian rice variety, MR220 by transferring the Pi9 gene from a donor parent into the recipient variety.…”

Molecular Breeding of Zheyou810, an Indica–Japonica Hybrid Rice Variety with Superior Quality and High Yield

“…Additionally, this technology has also made notable strides in rice breeding programs, where it has been used to identify markers associated with disease resistance, grain quality, and yield-related traits. For example, several studies have reported the successful use of KASP markers for identifying blast resistance genes, including Pi2 and Pi9 [20,21]. KASP markers have also been utilized to identify markers associated with other important diseases, such as bacterial blight [22] and bakanae disease [23].…”

Emergence of Rice Blast AVR-Pi9 Resistance Breaking Haplotypes in Yunnan Province, China

“…In Chinese monogenic lines, the resistance to rice blast fungus was introduced in 2000. In fact, five resistant genes were introduced, via the conventional breeding techniques, into the blast susceptible Japonica rice variety named Lijiangxin-tuan-heigu (LTH) [ 40 , 41 ]. At the protein level, Pi9 is a member of the NBS-LRR genes that show broad-spectrum resistance to different rice blast strains.…”