Somatic Cell Selection Criteria for Water Use Efficiency Using Genetically Differential Alfalfas

Development of crops that are water use efficient would make an important contribution to the conservation of this critical resource. Laboratory methods of genetic engineering, such as somatic cell selection, promise to be faster and more precise in the development of water use efficient crops compared to conventional breeding, provided that appropriate selection criteria can be identified. This project attempted to define somatic cell selection criteria by using a series of genetically related alfalfa populations bred by conventional methods to be increasingly more water use efficient.

The preliminary data generated by this project lend support to the following conclusions: (1) cell survival under osmotic stress was not an adequate cell selection criterion for genetic improvement of water use efficiency; and (2) titers of polyamines in cell cultures and whole-plants under stress corresponded to the degree of water use efficiency known to exist in the respective parental populations. If polyamine titers represent biochemical indices of water use efficiency, they could be used to devise an appropriate whole-plant or cell selection strategy.