BIOTECHNOLOGY-DRIVEN BREEDING OF SOLANACEOUS VEGETABLE CROPS: ADVANCES IN IN VITRO CULTURE AND MARKER-ASSISTED SELECTION

Abstract

Solanaceous crops like tomato, brinjal, chilli and potato are vital for global food security. Traditional breeding methods face limitations, including being time-consuming, labour-intensive, and constrained by limited genetic diversity. In vitro and marker-assisted breeding techniques offer solutions to overcome these challenges. In vitro breeding includes embryo rescue, which helps in interspecific hybridization, and anther and microspore culture, which accelerates the production of homozygous plants. Protoplast fusion allows combining genetic material from incompatible species, while in vitro mutagenesis creates genetic variations through induced mutations. These techniques enable the use of wild relatives as sources of desirable traits, especially disease resistance. Marker-assisted breeding uses DNA markers linked to specific traits, enabling precise selection without the influence of environmental factors. Advances in genomics, particularly single nucleotide polymorphisms (SNPs), have enhanced marker-assisted selection, improving resistance to biotic and abiotic stresses, yield potential, and nutritional qualities. Specifically, in vitro techniques combined with marker-assisted breeding have shown synergistic effects. For instance, embryo rescue has been used to create hybrids between cultivated tomatoes and wild relatives with disease resistance genes. Anther culture facilitates rapid development of doubled haploid lines in eggplants. Protoplast fusion has enabled the transfer of disease resistance from wild species to cultivated eggplants. In vitro mutagenesis has induced drought tolerance in tomatoes. Marker-assisted selection is used to select disease resistance genes in tomatoes and to pyramid multiple resistance genes against late blight in potatoes. Marker-assisted backcrossing efficiently transfers specific genes while retaining the genetic background of the cultivated variety. Genomic selection uses genome-wide markers to predict the breeding value of individuals for complex traits like fruit quality in tomatoes and tuber yield in potatoes, enhancing genetic gain. These integrated approaches accelerate the development of improved solanaceous crop varieties with enhanced resilience and nutritional value.