The significance of magnesium for crop quality

Abstract

Background The quality of agricultural and horticultural products and its modulation by fertilization has increasingly received attention. However, whereas the importance of magnesium (Mg) as an essential plant nutrient is well established, the impact of Mg nutrition on quality parameters has only been rarely addressed. Scope This review aims at evaluating the available knowledge on the influence of Mg on produce quality. A short discussion on the term quality as used in this review is followed by an overview of the various functions of Mg in plant metabolism in relation to quality aspects. Finally, the available literature on Mg-associated effects on crop quality is critically surveyed. The question whether Mg application beyond yield optimum further improves crop quality is specifically addressed. Conclusion Increasing Mg supply on Mg-deficient sites tends to increase the quality of agricultural crops, particularly when the formation of quality traits is dependent on Mg-driven photosynthesis and assimilate translocation within the plant. In fruits and vegetables, ratios of Mg to other nutrients like Ca and K were shown to be a more reliable indicator of the quality response than the Mg status alone. Moreover, it is concluded that Mg doses beyond those required for maximum yield rarely induce a further improvement of produce quality.