Agronomy of Halophytes as Constructive Use of Saline Systems

Abstract

Extensive coastal sabkhas in the northern Gulf of California in North America are colonized by Distichlis palmeri, an endemic perennial grass that produces a grain that was harvested as a staple food by native Cocopah people. Previous short-term trials have shown good vegetative growth but low grain yields. During outdoor trials under anaerobic saline soil conditions of paddy-style irrigation, D. palmeri exhibited high salt tolerance, grain and biomass production. Reproductive maturity was reached four years after initial establishment of plants from seed and a 1:3 mixture of male and female plants produced 231-310 g m⁻² of grain, with nutritional content similar to domesticated grains, confirming the feasibility of developing D. palmeri as a perennial grain and biomass crop for salinized soils and water supplies. Salicornia bigelovii Torr., a cosmopolitan annual coastal marsh succulent, produces seed with high oil content and has been suggested as a potential cash crop for fuel production from saline irrigation but its domestication and development into a cost effective commodity has been slow. A breeding and selection program for agronomic traits that will provide multiple landscape and ecosystem services that could enhance cost benefits of the agronomy of S. bigelovii was initiated during a two year period while producing seed for a pilot system at the Masdar Institute in Abu Dhabi, U.A.E. A concept for a saline landscape designed to consume and concentrate saline waste streams was developed and demonstrates the feasibility and potential to support agronomy of halophytes within a built landscape ecology akin to coastal marsh systems. Exploration and development of potential services halophytes could provide and field testing of selected halophytes for their potential to produce food, fuel, fiber and habitat under designed and managed domestication in our salinized soils with saline waste irrigation needs our continued investigation.