Gene Pyramiding for Sustainable Crop Improvement against Biotic and Abiotic Stresses

Abstract

Sustainable agricultural production is endangered by several ecological factors such as drought, extreme temperatures, excessive salts, parasitic ailments, and insect pest infestation. These challenging environmental factors may have adverse effects on future agriculture production in many countries. In modern agriculture, conventional crop breeding techniques alone are inadequate for achieving the increasing population’s food demand on a sustainable basis. The advancement of molecular genetics and related technologies are promising tools for the selection of new crop species. Gene pyramiding through marker assisted selection (MAS) and other techniques have accelerated the development of durable resistant/tolerant lines with high accuracy in the shortest possible period of time for agricultural sustainability. Gene stacking has not been fully utilized for biotic stress resistance development and quality improvement in most of the major cultivated crops. This review emphasizes on gene pyramiding techniques that are being successfully deployed in modern agriculture for improving crop tolerance to abiotic and biotic stresses for sustainable crop improvement.

RNA-Based Technologies for Engineering Plant Virus Resistance

“…The use of virus-resistant crop varieties is a traditional and efficient way to reduce losses caused by viral infections. However, conventional antiviral breeding strategies, even augmented with modern molecular techniques such as quantitative trait locus (QTL) mapping, marker-assisted selection, and whole-genome sequence-based approaches, are slow and laborious and require monitoring of large crop populations over multiple generations [ 1 ].…”

Molecular Breeding Strategy and Challenges Towards Improvement of Downy Mildew Resistance in Cauliflower (Brassica oleracea var. botrytis L.)

“…Marker-assisted gene pyramiding of resistance QTLs have been successfully applied in several crops consequently producing a number of varieties and lines with improved resistances against biotic stresses, such as late blight, bacterial blight, gall midge, mosaic viruses, powdery mildew and many abiotic stresses, such as salinity, drought, heat, and cold with a higher yield and desired nutritional quality (reviewed by Dormatey et al, 2020 ). Especially, the multi-loci polymerization resistance breeding is a success story in rice where plant scientists successfully utilized this technique to accomplish durable resistance against various diseases such as gall midge ( Das and Rao, 2015 ), blast ( Jamaloddin et al, 2020 ), brown planthopper ( Liu et al, 2016 ), bacterial blight ( Singh et al, 2001 ; Joseph et al, 2004 ; Jamaloddin et al, 2020 ; Ramalingam et al, 2020 ), sheath blight ( Ramalingam et al, 2020 ), blast and bacterial blight ( Narayanan et al, 2002 ), bacterial, sheath blight and stem borer ( Datta et al, 2002 ) etc.…”

Stacking for future: Pyramiding genes to improve drought and salinity tolerance in rice

“…To develop multi‐stack hybrids, gene stacking is a strategy to successfully introduce one or more transgenes by crossing the desired parents having different transgenes. The conventional crop breeding strategies utilize traditional techniques and routine natural processes that require extensive field trials (Dormatey et al, 2020; Janila et al, 2016). These strategies include recurrent selection, iterative hybridization, backcross breeding, and pedigree crossing (Figure 1).…”

“…Plant breeders use MAS to transfer genes from pyramided lines into the required crop to enhance the proportion of the desired population of improved genotypes (Das & Rao, 2015; Magar et al, 2014; Pradhan et al, 2015; Shamsudin et al, 2016). By using MAS, plant scientists successfully utilize genes/QTL allele‐linked markers to improve qualitative as well as quantitative traits against abiotic stress such as drought, besides monitoring these polygenic traits at a time (Dormatey et al, 2020). There are several recent reviews published on this approach (for reference see Gouda et al, 2020) and therefore, presenting the details of this approach is beyond the scope of this review.…”