Plants in remediating salinity-affected agricultural landscapes

Abstract

Soil salinity is a widespread problem throughout the world. Salinization makes productive land unproductive. This problem can be addressed by non-plant based (e.g., leaching of salts, chemical amelioration of soils, structural engineering modifications) and eco-friendly, plant-based remediation (e.g., phytoremediation). Non-plant based remediation provides rapid outcomes. However, they have several inherent problems, viz., they are energy and cost intensive, they need to be site specific, and are usually unsuitable in managing vast landscapes. In contrast plant-based remediation, viz., phytoremediation, is a slower process, but is economical and eco-friendly. Phytoremediation is applied in areas that not only suffer salinity, but also in areas that include heavy-metal leachates such as mine areas and in landscapes that suffer sodicity. Further to improving soils by bringing them to near-natural conditions, phytoremediation, a worthwhile eco-friendly effort, provides many additional benefits such as improving nutrient availability in the restored soil. Keeping these in view, this article attempts to provide a comprehensive overview of salinity and its effect on plants, salinity-tolerance mechanisms in selected plants, various plant-based salinity remediation and management practices, such as phytoextraction, phytostabilization, phytotransformation, phytovolatilization, and rhizodegradation, and their contextual relevance. This overview while comprehensively summarizing the scientific bases in the historical and current developments in managing salinity-afflicted landscapes, should equip interested people in recruiting environmentally friendly management of salt-affected agricultural landscapes especially in developing nations.