Genetic and molecular breeding perspectives on developing abiotic stress tolerant pea (Pisum sativum L.)

Pea is an important cool-season legume crop of the genus Pisum used for food and feed due to its high protein content. Pea plants often experience limitations in their potential productivity due to various abiotic stresses such as heat, drought, salinity and frost. These stresses exhibit complex quantitative inheritance, rendering conventional breeding slow and laborious due to long generation cycles. This underscores the need for genomic accelerated breeding approaches. Therefore, this review provides detailed insights into significant abiotic stresses affecting pea yield, available genetic resources, tolerant genotypes developed, and genomic advancements like reference genome information, QTL mapping, GWAS, transcriptomics, proteomics, and transgenics. These techniques enabled the identification of stress-tolerant gene(s) within the pea gene pool and their introgression into elite varieties to accelerate genetic gains in a breeding program. Additionally, advances and accomplishments achieved using cutting-edge techniques viz., gene editing, speed breeding, phenomics, genomic selection, epigenetic breeding, functional marker development and allele mining are discussed as time-efficient strategies for developing novel pea phenotypes resilient to abiotic stress. Integrating conventional breeding with advanced molecular and modern omics techniques will revolutionize the pea abiotic stress tolerance breeding program.