title: Chemical- and irradiation-induced mutants of indica rice IR64 for forward and reverse genetics.
abstract: IR64, the most widely grown indica rice in South and Southeast Asia, possesses many positive agronomic characteristics (e.g., wide adaptability, high yield potential, tolerance to multiple diseases and pests, and good eating quality,) that make it an ideal genotype for identifying mutational changes in traits of agronomic importance. We have produced a large collection of chemical and irradiation-induced IR64 mutants with different genetic lesions that are amenable to both forward and reverse genetics. About 60,000 IR64 mutants have been generated by mutagenesis using chemicals (diepoxybutane and ethylmethanesulfonate) and irradiation (fast neutron and gamma ray). More than 38,000 independent lines have been advanced to M4 generation enabling evaluation of quantitative traits by replicated trials. Morphological variations at vegetative and reproductive stages, including plant architecture, growth habit, pigmentation and various physiological characters, are commonly observed in the four mutagenized populations. Conditional mutants such as gain or loss of resistance to blast, bacterial blight, and tungro disease have been identified at frequencies ranging from 0.01% to 0.1%. Results from pilot experiments indicate that the mutant collections are suitable for reverse genetics through PCR-detection of deletions and TILLING. Furthermore, deletions can be detected using oligomer chips suggesting a general technique to pinpoint deletions when genome-wide oligomer chips are broadly available. M4 mutant seeds are available for users for screening of altered response to multiple stresses. So far, more than 15,000 mutant lines have been distributed. To facilitate broad usage of the mutants, a mutant database has been constructed in the International Rice Information System (IRIS; http: //www.iris.irri.org) to document the phenotypes and gene function discovered by users.
authors.affiliation: Entomology and Plant Pathology Division, International Rice Research Institute, Metro Manila, Philippines.
authors.forename: Jian-Li
authors.initials: JL
authors.lastname: Wu
authors.forename: Chanjian
authors.initials: C
authors.lastname: Wu
authors.forename: Cailin
authors.initials: C
authors.lastname: Lei
authors.forename: Marietta
authors.initials: M
authors.lastname: Baraoidan
authors.forename: Alicia
authors.initials: A
authors.lastname: Bordeos
authors.forename: Ma Reina Suzette
authors.initials: MR
authors.lastname: Madamba
authors.forename: Marilou
authors.initials: M
authors.lastname: Ramos-Pamplona
authors.forename: Ramil
authors.initials: R
authors.lastname: Mauleon
authors.forename: Arlett
authors.initials: A
authors.lastname: Portugal
authors.forename: Victor Jun
authors.initials: VJ
authors.lastname: Ulat
authors.forename: Richard
authors.initials: R
authors.lastname: Bruskiewich
authors.forename: Guoliang
authors.initials: G
authors.lastname: Wang
authors.forename: Jan
authors.initials: J
authors.lastname: Leach
authors.forename: Gurdev
authors.initials: G
authors.lastname: Khush
authors.forename: Hei
authors.initials: H
authors.lastname: Leung
mesh_terms: D018744:DNA, Plant / Q000235:genetics / Q000302:isolation & purification; D030541:Databases, Genetic; D004852:Epoxy Compounds / Q000633:toxicity; D005020:Ethyl Methanesulfonate / Q000633:toxicity; D014644:Genetic Variation; D018745:Genome, Plant; D005838:Genotype; D007113:Immunity, Innate / Q000235:genetics; D009153:Mutagens / Q000633:toxicity; D009154:Mutation / Q000235:genetics*; D012275:Oryza / Q000187:drug effects* / Q000235:genetics / Q000528:radiation effects*; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D011839:Radiation, Ionizing; D012098:Reproduction / Q000235:genetics; D012639:Seeds / Q000235:genetics
chemical_list: D018744:DNA, Plant; D004852:Epoxy Compounds; D009153:Mutagens; C007366:diepoxybutane; D005020:Ethyl Methanesulfonate