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Rice blast, caused by the fungus Magnaporthe oryzae, and brown planthopper (BPH) infestation are two of the most destructive problems of rice production in China. The development of multi-resistant varieties is widely recognized as the most efficient and environmentally friendly approach to controlling crop diseases and pests. Functional molecular markers (FMMs) have been developed from functional variants in the genic region associated with trait variation, greatly enhancing the efficiency of identifying and pyramiding valuable genes in crop breeding. In this study, two FMMs and a multiplex PCR amplification system were developed for two major broad-spectrum BPH resistance genes, Bph6 and Bph9. With the assistance of FMMs in the multi-resistant rice restorer-line development pipeline, two lines (Huahui7713 and Huahui3006) with blast and BPH resistance were developed by pyramiding three resistance genes Pigm, Bph6 and Bph9. Two new hybrid rice varieties, Weiliangyou7713 and Xuanliangyou3006, derived from Huahui7713 and Huahui3006, have been developed and commercialized in China. Weiliangyou7713 and Xuanliangyou3006 exhibit enhanced resistance to both blast and BPH, while maintaining optimal yield and grain quality. The adoption of Weiliangyou7713 continues to expand, now being cultivated on a large scale, which is promising for its future role in reducing the dependence on chemical fungicides and pesticides in rice production. This suggests that the implementation of Huahui7713 and Huahui3006 in targeted breeding programs could be highly beneficial for developing rice varieties with strong resistance to blast and BPH. [ABSTRACT FROM AUTHOR]

Hybrid rice, as one of the most successful crops exploiting heterosis, has greatly contributed to global food security. Due to its high‐yield potential, approximately half of the rice‐growing area in China is planted with hybrid rice varieties. However, the extreme vulnerability of hybrid rice to various diseases and poor grain quality pose great challenges to rice breeders. Here, we report the development of five new restorer lines pyramiding the broad‐spectrum blast resistance gene Pigm and low/intermediate amylose content‐associated gene Wxb by marker‐assisted and phenotypic selection. All these new restorer lines showed enhanced blast resistance in the disease nursery compared with the original restorer lines and had low‐to‐intermediate apparent amylose contents, ranging from 11.3% to 14.2%. Genetic background analysis based on next‐generation sequencing indicated that the proportion of Gumei 4 (donor of Pigm) genome in the five new restorer lines ranged from 9.89% to 21.69%. Eight of their derived hybrid combinations, which exhibited better grain quality and higher levels of blast resistance, have been certificated for commercial release in different ecological regions of China. Among them, Jing‐Liang‐You 3189, Yue‐Liang‐You 3189, Jing‐Liang‐You 1074 and Long‐Liang‐You 3188 meet the national standards for superior‐quality rice in China. These results confirmed the success of developing elite restorer lines through marker‐assisted and phenotypic selection, and these new restorer lines have great potential in developing more elite hybrid rice combinations. [ABSTRACT FROM AUTHOR]