Triacontanol priming as a smart strategy to attenuate lead toxicity in Brassica oleracea L.

The most prevalent heavy metal pollutant in the environment is lead (Pb). Lead potentially contribute 10% of overall heavy metal contamination. Lead uptake by plants has been found to have an impact on their metabolic functions, photosynthetic activity, growth, and productivity. The current experiment was conducted to investigate the impact of triacontanol (Tria) for attenuating Pb stress in Brassica oleracea var. italic (broccoli). Three different Tria concentrations (10, 20 and 30 mu mol L-1) were used to prime broccoli seeds. Growth of broccoli was reduced when exposed to Pb-driven toxicity. Additionally, Pb had a deleterious impact on the protein quantity, stomatal conductance, transpiration and photosynthetic rate. Nevertheless, plants grown from seeds primed with Tria2 (20 mu mol L-1 Tria) exhibited improved morphological characteristics, uptake of mineral content (Mn+2, Zn+2, K+1, Na+1) along with biomass production. There was 1.6-fold increase in photosynthetic rate, the phenol (1.3 folds), and DPPH activity (1.2 folds) in seed primed with Tria2. Additionally, plants treated with Tria2 demonstrated enhanced MTI and gas exchange characteristics that improves plant stress tolerance under Pb stress. Seed priming with Tria can be used to increase plant tolerance to Pb stress as evidenced by the improved growth and biochemical characteristics of broccoli seedlings. NOVELTY STATEMENTA number of studies emphasize the beneficial effects of plant growth regulators on the growth and yield of agricultural crops. The priming of seeds with triacontanol in vegetable crops, however, is a concern about which we know remarkably little. In addition, the effects of triacontanol on Brassica oleracea L var. italica under lead stress on growth, biomass, and nutrient content are largely unknown. Thus, the objective of this study was to evaluate the effects of seed priming with triacontanol on the agronomic traits, physiochemical traits, and nutrient content of Brassica oleracea L. var. italica under lead stress.