Crop Yields as Affected by Salinity

Abstract

This chapter focuses on how plants respond to salinity and toxic elements (i.e., Na+, G, and B), the various factors that influence plant response to salinity, and the extent to which salinity affects crop yields. The salt tolerance of a crop can best be described by plotting its relative yield as a continuous function of soil salinity. For most crops this response function follows a sigmoidal relationship. The chapter shows the two-piece model fitted to actual grain yield data obtained in a salt tolerance experiment on corn. It also presents management strategies to maximize yields by controlling soil salinity. Regardless of the irrigation water supplies and quality available to the grower, irrigation practices must be managed to control soil salinity within an acceptable level. This requires that a favorable salt balance can be attained. A long-term salt balance can only be achieved at the farm scale or regional scale if there is adequate drainage.