The Effect of Use of the Biologically Active Substances in Alleviating the Stress Caused by Lead in Barley Seedling on the Basis of Biochemical and Physiological Parameters

Abstract

Plants are constantly exposed to a variety of stressors during their lives. One of such stressors is contamination of the environment with heavy metals. Lead is one of highly toxic metals and it significantly inhibits normal plant growth. The study aimed at assessing the degree of relieving the stress caused by 1 mM Pb(NO 3 ) 2 via different biologically active substances (AsA, GSH, PP, α-Toc, SA) on the basis of the measurement of morphological (root length, coleoptile length, fresh weight), biochemical (Pro, MDA, CAT, POX) and physiological (Chl a+b, Car) traits in 10-day leaves of spring barley of the cultivar Eunova under laboratory conditions. Pb-stress reduced the fresh weight, root length and coleoptiles of the barley tested. Lead increased lipid peroxidation and Pro content, enhanced CAT and POX activity, and significantly suppressed the photosynthetic pigments content. Among the substances used in the experiment, PP, α-Toc and GSH generally relieved the toxic effect of lead to the barley seedlings to the greatest degree.

Examining Nicotinamide Application Methods in Alleviating Lead-Induced Stress in Spring Barley

“…Literature reports indicate a decrease in morphological parameters under the influence of varying lead concentrations in wheat [34], beans [56], and tomatoes [57]. Our research [35,36] conducted on barley using the same lead dose showed a much more pronounced decrease in all investigated morphological parameters compared to this study. In studies conducted on MS media in vitro culture [35], there was a 46% decrease in root length, 59% decrease in seedling length, and 43% decrease in fresh weight compared to the control while, in experiments conducted on Petri dishes [36], the decreases were 81.8%, 36.6%, and 41.2%, respectively.…”

“…The results demonstrated a decrease in pigment content in plants growing in lead-contaminated soil compared to control plants. Similarly, other studies have shown that lead decreases pigment content compared to controls [13,33,35,36,78,84]. The reduced chlorophyll content under the influence of lead may be attributed to its inhibition of magnesium availability.…”

“…The study revealed significant induction of enzymes such as CAT and POX, along with increased levels of Pro and MDA in plants growing in lead-contaminated soil compared to control plants. Similar results were reported by Dey et al [74] for POX and by Jiang [75] for POX, Yang et al [76] for CAT, POX, MDA, Alamri et al [34] for CAT, MDA, Sędzik et al [35] for CAT, POX, Pro, MDA, Cândido et al [77] for CAT, MDA, Pirzadoh et al [78] for Pro, Navabpaur et al [73] for CAT, MDA, Khan et al [13] for CAT, POX, Pro, Ahmad et al [33] for Pro, Sędzik-Wójcikowska et al [36] for CAT, POX, Pro, MDA. However, conflicting results were presented by Verma and Dubey [55], Dey et al [74] for CAT, Sędzik et al [35] for CAT at the highest lead dose, and Li et al [79] for CAT and POX.…”

“…In recent years, numerous scientific studies have explored the use of exogenous substances to mitigate the toxicity of various abiotic stresses, including those induced by heavy metals. Effective alleviation of lead stress has been achieved through the application of substances such as brassinosteroids [23][24][25][26], auxins, cyto-kinins [27], salicylic acid (SA) [28,29] jasmonic acid (JA) [30], various organic chelates [31,32], glutathione (GSH) [33], and vitamins [34][35][36]. Various methods of introducing exogenous substances into plants exposed to heavy metals are documented in the literature.…”

“…Various methods of introducing exogenous substances into plants exposed to heavy metals are documented in the literature. For example, these substances can be applied in hydroponic systems [31,35,37], on Petri dishes [36], in vitro culture on MS media [35,38], or in soil [29,33]. They can also be applied as foliar sprays [29,37,39] or seed imbibition treatments [39].…”