Characterization and Fine Mapping of a Leaf Wilt Mutant, m3, Induced by Heavy Ion Irradiation of Rice

Abstract

A rice (Oryza sativa L.) mutant, named m3, was isolated from a population of the M2 generation derived from an indica accession, BBS, where the seeds of BBS were treated with carbon ion irradiation at a dosage of 100 Gy to produce mutants. The m3 mutant is primarily characterized by the production of abnormal wilted leaves by appearance on the main stem, and additional tillers at the 9‐leaf stage. This abnormal leaf‐wilt phenotype is temporary, persisting only to the 13‐leaf stage, after which subsequent new leaves on the main stem and tiller appear normal. The phenotypic change of m3 during the 9‐ and 13‐leaf growth stages was further confirmed at physiological and biochemical levels. Additionally, compared with the wild type (WT, BBS), the heading date of m3 was noticeably delayed. The numbers of grains per panicle were lower by 32.44% than that of the WT. Moreover, plant height, width of flag leaf, panicle weight per plant, panicle length, and seed‐setting rate of m3 were considerably lower than those of the WT. Our genetic analysis revealed that the mutant phenotype of m3 was controlled by a single recessive gene, designated m3(g). We used recessive F2 individuals and mapped the m3(g) locus to a 3824‐kb region near the centromere of chromosome 11. We also performed a MutMap approach to refine the m3(g) locus to a 1030‐kb region comprising 115 genes, but six genes show nonsynonymous mutations. This study provides essential information for the cloning of the m3(g) gene and demonstrates that the MutMap approach is powerful enough to map a target gene that is located in centromeric regions.

Genome-Wide Analysis of CCT Transcript Factors to Identify Genes Contributing to Photoperiodic Flowering in Oryza rufipogon

“…There have been great successes in introducing desired traits from wild rice into cultivated rice, such as cytoplasmic male sterile source ( Lin and Yuan, 1980 ). In this study, we obtained OrCCT genes with the strategy of the reference genome-based gene family identification, which is time-efficient compared with traditional methods of genetic mapping ( Peng et al, 2019 ).…”

Multi-generation study of heavy ion beam-induced mutations and agronomic trait variations to accelerate rice breeding

“…Researchers have used HIB to construct a large number of mutants and rich varieties in model plants( Tanaka et al., 2002 ; Kitamura et al., 2004 ; Magori et al., 2009 ; Du et al., 2018 ; Du et al., 2021 ), crops ( Abe et al., 2002 ; Tanaka et al., 2002 ; Ishikawa et al., 2012 ; Liu et al., 2013 ; Zhang et al., 2022 ) and ornamental plants ( Yamaguchi et al., 2009b ; Hase et al., 2010 ; Matsumura et al., 2010 ). Various types of rice mutants have been generated by HIB irradiation, including plant height variants, leaf variants ( Peng et al., 2019 ), low cadmium absorption( Ishikawa et al., 2012 ), grain variants ( Li et al., 2017 ; Jiang et al., 2019 ), UV-B insensitive mutants ( Takano et al., 2013 ), and salt-alkali tolerance ( Zhang et al., 2022 ).…”

A new method for mutation inducing in rice by using DC electrophoresis bath and its mutagenic effects

“…However, spontaneous mutation rates for higher plants are low, ranging from 10 -5 to 10 -8 , thus, mutagenesis is an important strategy to increase mutation frequencies 6 . The main mutagens are physical mutagens such as X-rays 7-9 , γ-irradiation 10-12 and ion beams [13][14][15][16] , chemical mutagens such as ethyl methane sulfonate 17 and sodium azide 18,19 . Scientists have developed rice varieties with various excellent traits, e.g.…”