Improvement of crop production under saline stress by a biohydraulic approach

Abstract

One of the most restricting factors for horticultural production in the world, especially in arid and semiarid areas, is soil salinization. The “hydraulic” and “biological” approaches to this problem focus on the management, cultivation, or development of plants able to thrive on salt-affected soils by improved techniques of irrigation and innovative treatments to plants. This chapter reviews strategies by which plants can be enabled to grow on saline soils. The first component of this approach is based on irrigation methods as the subsurface drip irrigation (SDI), which is becoming popular, as it has revealed to be the most efficient irrigation system. The second component of our approach deals with selecting salt-tolerant lines/genotypes of potential crops and with new biological treatments to plants. For achieving this goal, it is necessary to gain deeper insight into the physiological/biochemical changes induced by the salt stress, which are attributable to detrimental effects of salt stress or are components of the adaptation mechanism. Indeed, exogenous applications of organic compounds and hormones as proline, polyamines, and brassinosteroids to plants under saline conditions have resulted in enhanced levels of these compounds, thereby improving the growth of plants and fruit yield. In addition, different crops differ in their response to exogenous application of these compounds because of their differing responsiveness to such applications. However, the use of such compounds seems to be plausible as components of the biohydraulic approach, so as to attain enhanced crop growth and yield under saline conditions.