Current progress in genetic and genomics-aided breeding for stress resistance in cucumber (Cucumis sativus L.)

Crop plants encounter various biotic and abiotic stresses that hinder life throughout their growth and development. These factors certainly affect the productivity and quality of the final produce. In the post-genomics era, the accumulation of genomic resources has widened the crop breeding for complex traits. Cucumber (Cucumis sativus L.) is an important vegetable crop and has been a model plant species to work on genomics in depth as it is the first horticulture crop genome to be sequenced. During the various phases of growth and development, cucumber is exposed to various diseases, insect-pests and abiotic stresses. Resistance breeding in cucumber demands availability of molecular markers associated with trait of interest. The small genome size and existence of full genome sequence of cucumber has facilitated the utilization of genetic and genomics resources to facilitate molecular breeding. The high-density maps and easily accessible high throughput sequencing technologies has allowed quick identification of molecular markers or cloning of candidate genes/QTL for several biotic and abiotic stresses. This review article is attempted to compile the up-to-date available information on genomics enabled tools for haplotype mapping, genetic linkage mapping and functional gene identification for important biotic and abiotic stresses in cucumber.