Plant Salt Tolerance

Abstract

As noted in previous chapters of this manual, the quality of irrigation water is an important factor in determining sustainability of agriculture on salt-impaired lands. For a number of reasons, the availability of lowsalinity irrigation supplies has led to (1) an interest in using alternative supplies, such as recycled wastewaters, and (2) innovative plant and water management strategies to mitigate the adverse effects of salt and specificion stresses these poor-quality waters may impose on plant growth, yield, and quality. A second motivating factor is the lack of suitable drainage outlets in many agricultural areas of the world. Drainage of irrigated lands is one of the requisites for sustaining agricultural productivity in a given region over the long term. Adequate drainage not only allows for better aeration in the crop rootzone but provides a means by which salinity and toxic elements can be managed and controlled. Reuse of drainage water for irrigation is one way of expanding the useable water supply while at the same time reducing drainage volume. This chapter provides a management perspective on (1) how plants respond to salinity and toxic elements (e.g., Na ϩ , Cl Ϫ , and B); (2) crop salt tolerance and the various factors that influence plant response to salinity; (3) the extent to which salinity affects crop yields and quality; and (4) management strategies to optimize yields by controlling soil salinity. It is not our intent to provide a comprehensive review of physiological effects of salinity crops. That topic is covered in detail in Chapter 6.

Recycled Urban Wastewater for Irrigation of Jatropha curcas L. in Abandoned Agricultural Arid Land

“…) [29]. Significant Bs increases in soil as a result of irrigation with RWW and DBW have been reported by other authors [32,33].…”

“…With regard to EC, the accumulation of soluble salts in the upper zone of the profiles (0-20 cm) with both types of water might be a potentially limiting factor for production in numerous crops [29]. High SAR values, such as those found in these soils, can lead to a deterioration of soil physical properties and, consequently, to a reduction in plant yield [30,31].…”

Chloride levels increase after 13 years of recycled water use in the Salinas Valley

“…However, in the shallow root zone (1 to 12 inches) at the control site and sites 2, 4 and 6, the EC e was 1.5 to 2.0 dS/m (deciSiemens per meter; data not shown), suggesting possible yield losses with lettuce and strawberries, though this is an acceptable level for celery; while at sites 5 and 8, values of EC e between 2.5 and 3.0 dS/m remained acceptable for artichokes, broccoli, cauliflower and rapini. The EC e values of about 4 dS/m found at sites 1 and 7 are just below the threshold yield loss for less-salt-sensitive artichokes (Grieve et al 2012). While the EC data indicates that decreases in yield are possible based on total salt load, Cl concentrations remained below yield loss thresholds specific to Cl sensitivity for all crops grown in the region at seven of the sites (excluding site 7).…”

Soil water energetic status and cowpea beans irrigated with saline water

“…Cowpea (Vigna unguiculata (L.) Walp.) is one of these crops and is classified as moderately sensitive to salinity (Grieve et al, 2012), although it has cultivars developed to increase its tolerance to saline stress, such as IPA 206, classified as moderately tolerant to salinity (Dantas et al, 2002).…”