Currently 40% of food crops are grown under irrigation, but on 30% of these acres crop yield is impaired by saline soil. Worldwide losses due to drought and salt stress are estimated higher than those brought about by pathogens and other pests, respectively.
In crops, photosynthetic capacity is impaired by salt stress, resulting in retarded development and reduced crop yield. But under sub-lethal stress no increased salt concentrations have been found inside chloroplasts. Therefore, complex multi-factorial interactions of metabolic pathways and regulation steps have been predicted. This assumption agrees with the finding that stress sensitivity of plants is under the control of a high number of genes, and gene action is non-additive.
