Mutagenesis: A coherent technique to develop biotic stress resistant plants

Modernization leads to frequent and remarkable alterations in the environmental factors which consequently affect the global agricultural productivity. Environmental factors can be broadly categorized into biotic and abiotic components. Biotic factors, which are represented by pests, bacteria, viruses, fungi, nematodes, etc., pose a severe threat to plants growth and development, thereby adversely impact the productivity. Taking this into consideration, crop improvement may prove to be a leading approach to ensure the sustainability of food and plant products. Modern agricultural practices rely upon agrochemicals and formulations for disease control that are responsible for causing environmental pollution and have detrimental effect on human health. Thus, development of stress resistance crop varieties must be a better approach in the current agriculture system. An array of genetic, biochemical and metabolic variations is required to produce such desirable alleles for appropriate crop improvement. Moreover, increasing genetic variation beyond natural variation is a crucial aspect of plant breeding programs. In connection, mutagenesis is one of the most prevalent tools to control plant stresses. To induce mutagenesis, techniques such as physical (gamma radiation, ultra-violet rays, etc.), chemical (ethyl methane sulfonate, methyl methane sulfonate, sodium azide, etc.) and gene editing (ZFN, TALEN, and CRISPR) are highly preferred by plant breeders. This review aims to provide an insight into mutation breeding techniques that facilitate the variable spectrum of agronomic and economic characters which is a prerequisite for successful crop improvement programs.