Analysis of accumulation and acute phytotoxic reactions of Ocimum basilicum to lead contamination in the initial phases of plant development

Abstract

It was noted that contamination of agricultural water and substrates with heavy metals is a serious environmental problem that can reduce both plant productivity and the safety of plant production used for food purposes or as forage. Lead, being one of the most common ecotoxicants among heavy metals, often ends up in water used for irrigating open and closed ground crop systems. The experimental model was based on the method for determining acute phytotoxicity according to GOST 33777-2016, with the introduction of the necessary corrective changes that do not conflict with GOST. Analytical work was based on the methods of atomic emission spectrometry and optical microscopy. Based on the data obtained, it is necessary to note the barrier function of basil seed exudate, which is expressed in the fact that the exudate absorbs most of the ecotoxicant compound from the solution, as well as deprivation of root hair growth and low variability of Pb(CH3COO)2 phytotoxicity for different varieties. The phytotoxicity of lead is expressed in this study along a gradient in which at the maximum concentration of Pb(CH3COO)2 we obtain an acute, but non-lethal toxic reaction. Exudate plays a protective role in the first days of seed germination, but does not exclude necrosis of root hairs and, subsequently, of the root not protected by exudate.