Molecular Plant Breeding 2024, Vol.15, No.6, 417-428 http://genbreedpublisher.com/index.php/mpb 424 of drought events. Recent studies have identified wheat germplasm with useful genetic sources for drought tolerance and reported QTLs associated with drought tolerance traits. These efforts have facilitated genome- and marker-assisted selection approaches, accelerating the development of drought-tolerant wheat varieties (Khadka et al., 2020a). Additionally, the evaluation of newly developed wheat genotypes for water deficit stress tolerance has highlighted the importance of physio-biochemical mechanisms in breeding programs. Genotypes that maintain better water relations, photosynthetic pigments, and antioxidative defense mechanisms under limited water supply have shown better yield performance, making them suitable for commercial application in drought-prone areas (Shahid et al., 2022). 6.3 Development of comprehensive resistance varieties The development of wheat varieties with comprehensive resistance to multiple diseases and environmental stresses has been achieved through various innovative breeding strategies. One such example is the identification of wheat genotypes with high levels of biotic and abiotic stress tolerance from the extensive collections conserved in national and international genebanks. These genotypes have been evaluated for trait-specific germplasm, leading to the development of varieties with combined resistance to multiple stresses (Kumar et al., 2022). Another case study involves the genome-wide association study of yield-related traits in wheat under normal and drought conditions. This study identified several QTLs and SNPs associated with yield and drought resistance, which have been transformed into kompetitive allele-specific PCR (KASP) markers. These markers facilitate the discovery of promising SNPs for yield-related traits and drought stress tolerance, accelerating the development of new wheat varieties with comprehensive resistance (Zhao et al., 2023). 7 Future Research Directions and Trends 7.1 Diversified strategies for wheat germplasm innovation Future research should focus on integrating multiple traits and diversifying breeding strategies to enhance wheat germplasm innovation. Traditional breeding methods, such as direct hybridization and backcrossing, have been successful but are time-consuming and limited in their ability to combine multiple desirable traits (Mondal et al., 2016). Modern approaches, including high-throughput phenotyping, genome sequencing, and genomic selection, offer promising avenues to accelerate the breeding process and improve the genetic gains in wheat (Mondal et al., 2016; Dwivedi et al., 2017). Additionally, the use of cisgenic techniques to transfer beneficial alleles within related species can help achieve durable resistance to diseases like rust (Mondal et al., 2016). An integrated approach involving multiple stakeholders and disciplines, such as molecular biology, genomics, agronomy, and stress tolerance, will be essential to address the global challenges of food security and climate change (Dwivedi et al., 2017). 7.2 Germplasm innovation in the context of climate change Climate change poses significant challenges to wheat production, necessitating the development of stress-tolerant germplasm. Strategies to enhance germplasm innovation in response to climate change should include the identification and utilization of genetic diversity from gene banks and wild relatives (Sehgal et al., 2015; Kumar et al., 2022). Advanced molecular techniques, such as genotype-by-sequencing and genome editing (e.g., CRISPR-Cas9), can be employed to identify and incorporate quantitative trait loci (QTLs) associated with drought and heat tolerance (Khadka et al., 2020a; Khadka et al., 2020b). High-throughput phenotyping platforms can also play a crucial role in evaluating physio-morphological traits at different growth stages, thereby improving the efficiency of breeding programs aimed at developing drought-tolerant wheat varieties (Khadka et al., 2020b). The integration of genetic, genomic, and phenotypic information will be vital for the rapid application of novel genetic discoveries in breeding programs (Dwivedi et al., 2017). 7.3 Integration of wheat germplasm innovation with precision agriculture The application of digital breeding and precision agriculture technologies holds significant potential for advancing wheat germplasm innovation. Precision agriculture techniques, such as remote sensing and data analytics, can enhance the monitoring and management of crop growth and stress responses (Mondal et al., 2016). Digital breeding tools, including genome-wide association studies (GWAS) and high-density SNP arrays, can help dissect
RkJQdWJsaXNoZXIy MjQ4ODYzMg==