Micronutrient constraints to crop production in the near east: Potential significance and management strategies

Abstract

This review focuses on the Near East, a region of the world where there is a dearth of information on micronutrients in soils and plants. The long history of cultivated agriculture in the region and the peculiar characteristics of the soils and the climate predispose towards problems with micronutrient deficiencies. Over 2 decades ago, a global study on micronutrients indicated deficiencies of iron (Fe) and zinc (Zn), and the likelihood of excess levels of boron (B), in some countries of the Near East. This review primarily addresses two focal points in the region, Pakistan on one side and the Syria/Lebanon/Turkey region on the other, reflecting the zones of activity of the two authors. It brings together and summarises published work in the areas of crop and soil micronutrient availability, their behaviour in soils in relation to crop growth, and strategies to deal with either deficiency or toxicity, including crop selection for tolerance and subsequent genetic manipulation. The review highlights the implications of micronutrient constraints in the soil-plant-human-animal continuum. While intensification of agricultural production is likely to accentuate micronutrient deficiencies in the region, other developments may counteract this trend. Nevertheless, as the trend for land use intensification increases, and as other nutrient constraints are eliminated, micronutrients will inevitably assume greater significance in future agriculture of the Near East.