Physiological and molecular analysis of iron and zinc deficiency stress in high seed iron and zinc accumulating barnyard millet lines

Abstract

Experiments were conducted at Department of Crop Physiology and Department newlineof Plant Biotechnology to study the physiological and molecular responses of barnyard newlinemillet lines under Iron (Fe) and Zinc (Zn) deficiency conditions. newlineIron and Zinc are the most essential micro-nutrients needed for the growth and newlinemetabolism of higher plants. Plants have evolved with multifaceted Fe and Zn newlinehomeostatic mechanisms that regulate their acquisition from the environment and the newlinemovement within the plant system. Plant establishes a tightly controlled system including newlinemetal specific uptake transporters and transcriptional regulators to balance the uptake, newlineutilization and storage of metal ions. Barnyard millet (Echinochloa frumentaceae), one of newlinethe minor millets is superior in Fe and Zn content compared to the most widely consumed newlinecereals like rice and wheat. In the present study, 19 barnyard millet accessions were newlinescreened for high Fe and Zn content in seeds by ionomic profiling. Out of 19 barnyard newlinemillet lines, MDU1 accumulated high Fe (14.57 g/100g) and Zn (2.18 mg/100g) in seeds, newlinewhereas, the least Fe (0.24 mg/100g) and Zn (0.82 mg/100g) accumulation was found in newlineACM-16-5. Phenotypic evaluation of MDU1 and ACM-16-5 revealed that under newlinecomplete Fe and Zn deficiency conditions, the performance of both the contrasting newlinephenotype was comparatively lower when compared with plants grown under control and newlineminimal Fe and Zn conditions. Since, Fe and Zn play an important role in various growth newlineand metabolic processes, the deficiency of these nutrients in plant system lead to newlinereduction in growth and development of both MDU1 and ACM-16-5. Comparing the newlineperformance of MDU1 and ACM-16-5 under complete Fe and Zn deficiency conditions, newlineMDU1 performed better than ACM-16-5 due to the efficient uptake and utilization of newlinethese micronutrients, particularly Fe. MDU1 recorded higher Fe in shoot and root under newlinecomplete Fe deficit condition, which was utilised for efficient nutrient remobilization newline