Breeding of pulses, especially chickpea, by exploiting genetic diversity using conventional methods has been practiced in the past. Nevertheless, these methods at present are inadequate for making any significant breakthrough to handle the world's ever-increasing food demand. In this bizarre scenario, induced mutations have emerged as big relief, and are largely exploited for developing improved high-yielding crop varieties and for discovering desired genes that control important agronomical traits. Gene mutation, leading to the quality advancement of well-adapted existing varieties, has been the pedestal for germplasm improvement. Pulses are more prone to biotic and abiotic stresses as compared to cereals. As a result, there is a serious need to develop such varieties having high resistance to the above-mentioned stresses. During the past eight and a half decades, around 3,139 improved crop varieties have been released globally derived either as direct mutants or from their progenies (http://mvgs.iaea.org). Vast numbers of these varieties like cereals, pulses, oil crops, root and tuber crops and ornamentals have been released in developing countries for cultivation, including India, resulting in massive economic impact. Lately, mutagenesis has received an immense impel for its use in a newfangled promising technique known as targeting induced local lesions in genomes. With the unfolding of novel biological fields such as genomics, functional genomics, bioinformatics and the emergence of other technologies based on these sciences, there has been an increased surge in induced mutations within the scientific community. The knowledge of functional and basic genetics of model legume crops will benefit chickpea breeders to comprehend that marker-assisted selection has great potential to develop biotic and abiotic stress-resistant varieties. The basic understanding of genes, which direct major agronomical traits, is essential for plant breeders to frame apposite approaches and execute them in breeding programmes for promising results. In this era, with growing human population, hunger ghosts are haunting millions of people all around. Under these circumstances, the salvaging step lies in tailoring better crop varieties embedded with superior proteins, minerals and high yield. Mutagenic agents, physical as well as chemical, are used to induce mutations and generate variations from which desired mutants may be selected. However, basic information vis-à-vis effectiveness of various mutagens and their possible role in generating polygenic variability is meagre among pulses in general and chickpea in particular. Hence, the present review condenses various facets of contemporary knowledge for pulse crop varietal improvement, particularly chickpea, through induced mutagenesis with special thrust on qualitative as well as yieldattributing traits.

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Vitamin and mineral deficiencies are prevalent in human populations throughout the world. Vitamin A deficiency affects hundreds of millions of pre-school age children in low income countries. Fruits of pepper (Capsicum annuum L.) can be a major dietary source of precursors to Vitamin A biosynthesis, such as β-carotene. Recently, pepper breeding programs have introduced the orange-fruited (of) trait of the mutant variety Oranzheva kapiya, which is associated with high fruit β-carotene concentrations, to the mutant variety Albena. In this manuscript, concentrations of β-carotene and mineral elements (magnesium, phosphorus, sulphur, potassium, zinc, calcium, manganese, iron and copper) were compared in fruit from P31, a red-fruited genotype derived from the variety Albena, and M38, a genotype developed by transferring the orange-fruited mutation (of) into Albena. It was observed that fruit from M38 plants had greater β-carotene concentration at both commercial and botanical maturity (4.9 and 52.7 mg / kg fresh weight, respectively) than fruit from P31 plants (2.3 and 30.1 mg / kg fresh weight, respectively). The mutation producing high β-carotene concentrations in pepper fruits had no detrimental effect on the concentrations of mineral elements required for human nutrition.

Although historically a surplus food producer, Bulgarian agriculture has faced a downturn in recent decades. Local legume cultivars have lost favour with farmers and the canning industry, due to their low productivity in comparison with imported ones. Diseases and abiotic stresses are the most important factors limiting the production of edible legumes, costing farmers hundreds of euros in lost revenue each year. The overall objective of our ongoing bean mutation breeding programme was to enrich the gene pool of Phaseolus vulgaris L. and to develop genotypes resistant to Xanthomonas axonopodis pv. phaseoli (Smith) (Xap) and Pseudomonas savastanoi pv. phaseolicola (Burkh.) (Psp) using EMS. An elite line and common cultivar (an heirloom and a snap bean type) in Bulgaria, were selected as parents and the chemical mutagen EMS was used for generating mutations. In total, 1000 seeds were treated and the two generated M1 populations were grown in the field. All M2 mutant plants (1650 from initial line IP564 and 2420 from initial cultivar 'Mastilen 11b') were grown in field conditions and a number of phenotypic changes were observed on these mutated plants. They were also screened for Xap disease resistance via leaf artificial inoculation under greenhouse conditions. Individual plant selection was performed for the putatively resistant M2 plants. In the M3 generation these lines were screened using artificial inoculation with Xap and Psp pathogens (leaves and pods) under field conditions. Selected M3-M4 lines with confirmed disease resistance were tested for fresh pod quality. Yield tests were started in M4 and M5 generations and, according to their productivity performance, mutants were advanced to the M6/M7 generation for validation. The expression patterns of genes putatively involved in the resistance reactions towards two races of Psp were determined using qRT-PCR for the specific and reference genes. In conclusion, 50 plants with visible morphological changes and/or increased tolerance to the two targeted bacterial diseases were selected. A total of 20 advanced mutant bean lines are currently being evaluated for their competitiveness in multiple sites.

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