Genetic Variability through Induced Mutation

*Faisal Saeed Awan, Bushra Sadia, Javaria Altaf, Madiha Habib, Kiran Hameed and Shabbir Hussain*

#### **Abstract**

The success of plant breeding is based on the accessibility of genetic variation, information about desired traits with well-organized approach that make it likely to develop existing genetic resources. Food security demands to break the yield barrier through increasing new cultivars which can adapt to wide range of environment. It is especially important to observe the character association for yield along with its components before recognizing novel technique to break the yield barrier. There are numerous methods for improved exploiting of the inherent genetic makeup of crops with heritable variations. It is recommended that recognized parental resources can also be induced to mutate for unmasking novel alleles of genes that organize the traits suitable for the crop varieties of the 21st century world. Chemical mutagens have extensively been applied to make genetic changes in crop plants for breeding investigation as well as genetic studies. Ethyl methane sulphonate (EMS) is the most frequently applied as chemical agents in plants. EMS normally induces GC → AT transitions in the genome causing mutated protein that performed different functions rather than normal. It is exposed that the utilization of EMS is an efficient approach for developing novel gene pool.

**Keywords:** ethyl methane sulphonate, mutation, genetic variability, singe nucleotide polymorphism

### **1. Introduction**

Plant breeding involved in rapid introduction of genetic variability in plants, to divulge them with desirable characteristics, through genetic mutation. Plant evolution and genetic breeding depends on the genetic variation that, not all come from spontaneous mutation rather it comes by genetic recombination within population and their interactions with environmental factors [1]. Conventional breeding depends on prevailed environmental genetic variations in wild and cultivated plants that require a large-scale backcrossing to incorporate it and stabilize it while, new mutation breeding strategy is less time consuming and easy that enhances the selection of desirable mutants [2]. Mutation breeding is an advancement of plant breeding where the induction of physical and chemical mutagens cause genetic variation. These variations are transferred to next generation through recombinant hybridization in meiosis [3]. Selection of breeding individuals only probable when there is a significant genetic variability exists [4]. Mutation breeding depends upon the transfer and stabilization of heritable characters that cause the variability [5].

**8**

s12859-020-03619-x

*Genetic Variation*

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Spontaneous and Induced mutations are the primary source of all variations exists in an organisms that may be plants or animals [6]. Genetic variability endorses the differences among the same species and its existence in population is essential for its survival with changing environment. Induced mutation with specific mutagens generates the individuals with desirable characters that can be further exploit in breeding to generate new verities in plants [7, 8]. Mutation was first recognized in the late nineteenth century by Hugo de Varies, when he was working on the 'rediscovery' of Mendel's laws of inheritance [6]. Chemical mutagens are less harmful and easily available for work. In plants, widely used chemical mutagen is EMS that is very effective in causing point mutation in genome [9]. Mutation approaches produces huge and minute effect on all types of phenotypic traits [6]. Induced mutation is helpful in growing novel cultivars of plants as seedless grapes and edible bananas [3, 10] also it bring out the novel color variants of tuber and root crops [11]. Mutagenesis also apply to improve dwarfness, early growth, resistance to biotic and abiotic stresses, and yield improvement as well as quality enhancements in plants [12–15].

Novel breeding techniques based on biological mutagenic agent are widely introduce in plants for targeted variation is also known as targeted genome editing [16]. These genome editing techniques cause the specific and precise genome mutations. It introduce targeted mutation by either insertion, deletion that disturbs the function of gene. CRISPER/Cas9 is a novel technique that introduce desired targeted mutation permanently inside the genome [17].
