Phenotypic, biochemical and genomic variability in generations of the rapeseed (Brassica napus L.) mutant lines obtained via chemical mutagenesis

Abstract

The phenotypic, biochemical and genetic variability was studied in M2-M5 generations of ethyl methansulfonat (EMS, 0.2%) mutagenized rapeseed lines generated from canola, ‘00’, B . napus cv. Vikros. EMS mutagenesis induced extensive diversity in morphological and agronomic traits among mutant progeny resulted in selection of EMS populations of B . napus - and B . rapa- morphotypes. The seeds of the obtained mutant lines were high-protein, low in oil and stabilized in contents of main fatty acids which make them useful for feed production. Despite the increased level of various meiotic abnormalities revealed in EMS populations, comparative karyotype analysis and FISH-based visualization of 45S and 5S rDNA indicated a high level of karyotypic stability in M2-M5 plants, and therefore, the obtained mutant lines could be useful in further rapeseed improvement. The revealed structural chromosomal reorganizations in karyotypes of several plants of B . rapa- type indicate that rapeseed breeding by chemical mutagenesis can result in cytogenetic instability in the mutant progeny, and therefore, it should include the karyotype examination. Our findings demonstrate that EMS at low concentrations has great potential in rapeseed improvement.

A Novel Banana Mutant “RF 1” (Musa spp. ABB, Pisang Awak Subgroup) for Improved Agronomic Traits and Enhanced Cold Tolerance and Disease Resistance

“…Dwarfism is one of the most important objectives of banana breeding because dwarf plants have strong resistance to wind or flood disturbances (Cho et al, 2016 ; Wang et al, 2021 ). Recent work found that chemical mutagenesis is capable of inducing dwarf and semi-dwarf mutants from high-stem banana varieties (Aslam et al, 2016 ; Amosova et al, 2019 ). In our study, the gene locus controlling banana plant height was sensitive to the EMS mutagen, leading to abundant dwarf or semi-dwarf mutant offspring obtained.…”

Development and screening of EMS mutants with altered seed oil content or fatty acid composition in Brassica napus

“…Based on previous EMS mutagenesis studies in B. napus (Wang et al, 2008;Harloff et al, 2012;Amosova et al, 2019) and our examinations of various EMS concentrations on the germination rate, 0.8% EMS was applied in this study. Previous EMS mutagenesis studies in crops usually screened a few thousand mutagenized plants, and numerous mutants have been successfully identified in peanut (Fang et al, 2012), cucumber (Wang et al, 2014), eggplant (Xi-ou et al, 2017), soybean (Espina et al, 2018), rice (Takagi et al, 2015) and B. napus (Wang et al, 2008;Harloff et al, 2012;Amosova et al, 2019). In order to identify adequate mutants for gene cloning and breeding, we generated a M2 population with approximately 100 000 plants in this study.…”

“…The creation of mutant materials by EMS produces stable genetic variation at the genome level with a high density of point mutation, and valuable mutants can be directly applied to breeding without gene-modified controversy (Steven et al, 2004). EMS-induced mutagenesis has been widely used in different crops, such as soybean (Lakhssassi et al, 2017;Espina et al, 2018), maize (Lu et al, 2018b), rice (Serrat et al, 2014;Takagi et al, 2015), wheat (Chen et al, 2012), rapeseed (Wang et al, 2008;Harloff et al, 2012;Amosova et al, 2019) and tomato (Shirasawa et al, 2016). EMS-induced mutagenesis has been shown to be an effective way to obtain germplasm resources in the quality breeding of rapeseed, especially in the development of rapeseed cultivars with high oleic acid and low linolenic acid.…”

Stress Management in Plants: Examining Provisional and Unique Dose-Dependent Responses

“…Initially, a basic understanding of genomic instability in plants came from IR studies; however, further research has revealed that this type of instability can also occur as a result of other methods used in plant breeding, for instance, physical, chemical, or radiation mutagenesis. Recent studies have shown that stress-inducing factors, such as low concentrations of EMS [ 165 ], herbicides [ 166 ], and salt and heat stress [ 142 ], can also lead to genomic instability.…”