Changes in root morphology and nutrient uptake in wheat plants with varied potassium and magnesium supply

Official URL: http://risc01.sabanciuniv.edu/record=b1659290 (Table of Contents)

Mineral nutrient deficiencies on agricultural soils is a widespread problem affecting crop productivity worldwide. This study was conducted to investigate the effects of potassium (K) and magnesium (Mg) supply on biomass production, root morphology and uptake of other mineral nutrients in wheat (Triticum aestivum cv. Ceyhan-99). Changes in root morphology as well as nutrient uptake by roots were monitored under various K and Mg treatments. Results showed that K and Mg deficiency significantly reduced shoot and root growth and induced changes in nutrient uptake by roots. K deficiency reduced nitrate (NO3 -) and phosphorus (P), but increased Mg uptake by roots. In general, all root morphological attributes analyzed were significantly affected by low K and Mg supply. However, root length, root area, root volume and number of tips were the most affected attributes which lead to severe reductions in nutrient acquisition and use efficiency. Moreover, K deficiency resulted in impaired use of absorbed nitrogen (N) in protein biosynthesis. Total free amino acid concentration increased sharply in response to K starvation and resulted in severe inhibition of N uptake by roots due to the negative feedback effect. It is concluded that ensuring adequate K and Mg nutrition is required to maximize agricultural production and to improve use efficiency of nutrients applied to agricultural lands.