Department of Botany, The Women University, Multan, Pakistan.
Department of Forestry, Bahauddin Zakariya University, Multan, Pakistan.
PLoS One. 2021 Jul 12;16(7):e0254602. doi: 10.1371/journal.pone.0254602. eCollection 2021.
Cadmium (Cd) is a widespread heavy metal, which commonly exert negative impacts on agricultural soils and living organisms. Foliar application of seed water extract of black cumin (Nigella sativa L.) can mitigate the adverse impacts of Cd-toxicity in plants through its rich antioxidants. This study examined the role of seed water extracts of N. sativa (NSE) in mitigating the adverse impacts of Cd-toxicity on maize growth. Two maize genotypes (synthetic 'Neelum' and hybrid 'P1543') were grown under 0, 4, 8 and 12 mg Cd kg-1 soil. The NSE was applied at three different concentrations (i.e., 0, 10 and 20%) as foliar spray at 25 and 45 days after sowing. All Cd concentrations had no effect on germination percentage of both genotypes. Increasing Cd concentration linearly decreased root and allometric attributes, gas exchange traits and relative water contents of hybrid genotype. However, gas exchange traits of synthetic genotype remained unaffected by Cd-toxicity. Overall, hybrid genotype showed better tolerance to Cd-toxicity than synthetic genotype with better germination and allometric attributes and less Cd accumulation. Foliar application of NSE lowered negative effects of Cd-toxicity on all studied traits, except relative water contents. In conclusion, foliar application of NSE seemed a viable option to improve maize growth in Cd-contaminated soil.
镉（Cd）是一种广泛存在的重金属，通常对农业土壤和生物产生负面影响。通过其丰富的抗氧化剂，黑种草（Nigella sativa L.）种子水提取物的叶面喷施可以减轻 Cd 毒性对植物的不利影响。本研究探讨了黑种草种子水提取物（NSE）在减轻 Cd 毒性对玉米生长的不利影响中的作用。两种玉米基因型（合成型“Neelum”和杂交型“P1543”）在 0、4、8 和 12 mg Cd kg-1 土壤下生长。在播种后 25 和 45 天，以 0、10 和 20%三种不同浓度（即 0、10 和 20%）作为叶面喷施应用 NSE。所有 Cd 浓度对两种基因型的发芽率均无影响。随着 Cd 浓度的增加，杂种基因型的根和比例性状、气体交换特性和相对含水量线性下降。然而，Cd 毒性对合成基因型的气体交换特性没有影响。总的来说，与合成基因型相比，杂种基因型对 Cd 毒性具有更好的耐受性，表现出更好的发芽和比例性状以及较少的 Cd 积累。叶面喷施 NSE 降低了 Cd 毒性对所有研究性状的不利影响，除相对含水量外。总之，叶面喷施 NSE 似乎是一种可行的选择，可以改善 Cd 污染土壤中玉米的生长。
