Marker-assisted breeding for abiotic stress tolerance in horticultural crops

Abstract The horticultural crops are predominantly short duration crops mostly grown on small patches of land and require a very specific climatic and edaphic requirement to complete their growth and production cycle. The extreme weather events and various abiotic stresses have been reported to cause considerable damage to many horticultural crops. The effects of abiotic stresses like drought, temperature, cold, salinity, and heavy metals on the yield performance are more pronounced in vegetables and fruit crops. To cope up with these abiotic challenges, different plant breeding programs have already been carried out, focusing on the development of abiotic stress-tolerant varieties. Recently, the economic uses of utilizing molecular markers of interesting genes in plant breeding programs have emerged out as a powerful tool in molecular breeding. The potential benefits of these identified markers of bona fide specific traits enhanced the feasibility and success of this marker-assisted selection (MAS). In conventional breeding programs, the selection is carried out based on morphological traits without the knowledge of genetics. Impact of abiotic factors and recent yield issues, characters that control environmental stress tolerance, mineral, osmotic requirement, etc., are the main concerns for horticultural crops. The molecular MAS technology suggests rapid and cost-effective progress in selecting abiotic stress-acclimated horticultural plants with expanding accuracy. The molecular-aided selection has potential in pyramiding target traits/genes in a single progeny plant more precisely and conveniently with little\accidental harms. Marker-tagged abiotic stress-resistance genes can be easily combined without the need for phenotypic screening. As it is a cost-effective and less time-consuming strategy, it can be suggested for long-term improvement in stress tolerance of horticultural crops with some limitations.