Morphological phenotyping and genetic analyses of a new chemical-mutagenized population of tobacco (Nicotiana tabacum L.)

Abstract

A novel tobacco mutant library was constructed, screened, and characterized as a crucial genetic resource for functional genomics and applied research. A comprehensive mutant library is a fundamental resource for investigating gene functions, especially after the completion of genome sequencing. A new tobacco mutant population induced by ethyl methane sulfonate mutagenesis was developed for functional genomics applications. We isolated 1607 mutant lines and 8610 mutant plants with altered morphological phenotypes from 5513 independent M2 families that consisted of 69,531 M2 plants. The 2196 mutations of abnormal phenotypes in the M2 putative mutants were classified into four groups with 17 major categories and 51 subcategories. More than 60% of the abnormal phenotypes observed fell within the five major categories including plant height, leaf shape, leaf surface, leaf color, and flowering time. The 465 M2 mutants exhibited multiple phenotypes, and 1054 of the 2196 mutations were pleiotropic. Verification of the phenotypes in advanced generations indicated that 70.63% of the M3 lines, 84.87% of the M4 lines, and 95.75% of the M5 lines could transmit original mutant phenotypes of the corresponding M2, M3, and M4 mutant plants. Along with the increased generation of mutants, the ratios of lines inheriting OMPs increased and lines with emerging novel mutant phenotypes decreased. Genetic analyses of 18 stably heritable mutants showed that two mutants were double recessive, five were monogenic recessive, eight presented monogenic dominant inheritance, and three presented semi-dominant inheritance. The pleiotropy pattern, saturability evaluation, research prospects of genome, and phenome of the mutant populations were also discussed. Simultaneously, this novel mutant library provided a fundamental resource for investigating gene functions in tobacco.

Insight into the B3Transcription Factor Superfamily and Expression Profiling of B3 Genes in Axillary Buds after Topping in Tobacco (Nicotiana tabacum L.)

“…Fortunately, the genomes of four species of Nicotiana, including several cultivars of the allotetraploid tobacco have been sequenced [115,116,117,118]. In addition, mutant libraries of tobacco based on both activation-tagging and chemical mutagenesis have been constructed and characterized [119,120]. These resources provide an opportunity to enhance our understanding of the function of B3 gene families in branching development in tobacco compared with those of Arabidopsis.…”

Genetic Mapping and Identification of the Gibberellin 3-Oxidase Gene GA3ox Leading to a GA-Deficient Dwarf Phenotype in Pumpkin (Cucurbita moschata D.)

“…EMS mutation technology and BSA technology have greatly improved the efficiency of new germplasm creation and gene function research. Ethyl methane sulfonate had a mutagenic effect, and since then, this method has been used in several different plants [17,43]. This method is widely used to induce mutants and construct mutant libraries because of its relatively low price, strong operability, and reusability.…”

Characterization and Mapping of a Novel Premature Leaf Senescence Mutant in Common Tobacco (Nicotiana tabacum L.)

“…The yl1 mutant was identified from the chemical mutagen EMS induced library derived from the common tobacco variety HonghuaDajinyuan (HD) [57]. The yl1 mutant was identified from one the M2 lines, and further verified in the M3 and M4 generation.…”