Tools and approaches for the genetic improvement of salinity tolerance in alfalfa

Authors: Sandhu, Devinder; Suarez, Donald; Ferreira, Jorge; CORNACCHIONE, MONICA - Instituto De Clima Y Agua (INTA); KAUNDAL, RAKESH - Utah State University

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/31/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Salinity is a critical problem faced by agriculture throughout the globe. Alfalfa, a most widely cultivated perennial forage legume, is increasingly facing the salinity threat in the arid and semi-arid regions. Understanding genetic determinants regulating salinity tolerance in alfalfa will be critical in developing genetic material tolerant to salinity. Screening of hundreds of alfalfa genotypes in a long-term salinity experiment showed that selections based on total biomass and ion composition were highly effective. The reduction in biomass yield under salinity was due to a reduction in shoot number rather than shoot height. The genetic analyses led to the identification of various genes involved in salt tolerance, including genes involved in ion transport, ion partitioning, and tissue tolerance. Gene expression analyses allowed us to classify genotypes based on their ability to regulate different components of the salt tolerance mechanisms. Screening of a segregating population generated by crossing two salt-tolerant parents resulted in the isolation of highly salt-tolerant genotypes that can tolerate the salinity of half seawater. These salt-tolerant genotypes can be utilized in breeding programs to develop alfalfa genotypes for salt-affected regions in the United States.