Changes of plant biomass partitioning, tissue nutrients and carbohydrates status in magnesium-deficient banana seedlings and remedy potential by foliar application of magnesium

Abstract

Magnesium (Mg) is involved in many biochemical and physiological processes affecting plant growth and development. Although Mg deficiency is a widespread problem in banana production, detailed study of physiological responses to Mg deficiency in banana crops is lacking. Here, we characterized plant biomass partitioning, tissue nutrient distribution and carbohydrates status of banana seedlings grown under sufficient and deficient Mg supply. We also studied the potential of remedying Mg deficiency by foliar application of Mg. Mg deficiency severely decreased plant growth, especially biomass partitioning from rhizome to root and led to a reduction of root/shoot dry weight ratio. Under Mg deficiency, plant Mg status was reduced but the concentrations of N, P and K were increased in most tissues. Mg deficiency caused an overall reduction in tissue glucose and fructose contents, and accumulation of sucrose, amylose and amylopectin in leaves. Sucrose, amylose and amylopectin contents were however reduced in pseudostem, rhizome and root of plants with Mg deficiency. Foliar application of Mg to Mg-deficient plants completely recovered banana plant growth, nutrients and carbohydrates status.