Conjoint effect of indole-3-acetic acid and vitamin B1 on nutrient acquisition and seed oil physicochemical properties of Zea mays L. under arsenic intervention

Abstract

Human or natural activities have made the rhizosphere prone to heavy metal (loid) stresses that involve the fluctuating dynamics of mineral-nutrient translocation in plants. To control the nutrient deficiency and growth of plants, the use of plant hormones and vitamins can effectively mediate the reverse effects of crops grown in As-contaminated soils. The current trial was managed to reverse the toxic sequels of As-stress with foliar application of 0.03 mM of indole-3-acetic acid (I3A) and 250 mg/L of vitamin B1 (Vit.B1) in maize (Zea mays L.) cultivars (cv. Pearl and cv. Akbar) under diverse As- levels (50, 100 mg/kg). Applied As-stress (100 mg/kg) increased As-levels in shoot (119.23-fold, 126.38-fold), and root (82.03-fold, 90.69-fold), while Vit.B1 and I3A combined application reduced the As-uptake in shoot (1.66-fold, 1.31-fold) and root (2.05-fold, 1.33-fold), respectively, of cv. Akbar and cv. Pearl under As-level (100 mg/kg). Furthermore, combined application of Vit.B1and I3A significantly increased the uptake of shoot minerals; potassium (59.7, 55.33%), calcium (30, 28.5%), phosphorus (80.86, 70.37%), nitrogen (32.52, 29.87%), ferrous (50.71, 34.81%), manganese (8.41, 2.26%), and seed oil physicochemical properties such as oil saponification values (42.15, 61.35%), iodine values (40.96, 38.52%), refractive index (42.67, 29. 45%),while decreasing the oil unsponifiable values (39.32, 24.49%), para-ansidine values (22.39, 16.52%), oil density (16.36, 14.16%) and oil free fatty acids (38.10, 35.98%), respectively, of cv. Pearl and cv. Akbar under As-stress level (100 mg/kg). Overall outcomes encourage the application of Vit.B1 and I3A in enhancing the nutrient uptake and seed oil quality in maize to counter As-stress. However, much investigation is still required, and open field trials should be managed to unveil the putative role of Vit.B1 and I3A at the molecular level.