Environmental Biology Unit, Department of Plant Biology, Faculty of Life Sciences, P. M. B. 1515, University of Ilorin, Ilorin, 240003, Nigeria.
Environmental Biology Unit, Department of Plant Biology, Faculty of Life Sciences, P. M. B. 1515, University of Ilorin, Ilorin, 240003, Nigeria.
J Biotechnol. 2020 Feb 20;310:54-61. doi: 10.1016/j.jbiotec.2020.01.009. Epub 2020 Jan 31.
The study was conducted to investigate the effects of foliar-intervention of nano-TiO on Cd toxicity in cowpea plants. Cowpea plants were exposed to Cd toxicity at 10 mg/kg soil for 21 days and afterwards, subjected to six episodes of foliar application of nano-TiO intervention. Results showed that foliar-applied nano-TiO significantly promoted chlorophyll b and total chlorophyll contents after Cd stress as compared to Cd-stressed plants without the intervention. Interestingly, Cd contents of roots, shoots and grains were significantly reduced (p < 0.05) after nano-TiO sprays compared to Cd-stressed plants. However, the Cd contents in edible tissues (leaves and seeds) after interventions remained above recommended threshold. Furthermore, nano-TiO interventions promoted stress enzymes activity in both roots and leaves as well as increased Zn, Mn and Co levels in seeds compared to Cd-stressed plants without intervention. Estimated daily intake of Cd in leaves and seeds for adult subpopulation exceeded the WHO recommended daily intake by some folds in Cd-stressed and nano-TiO-treated plants. The health risk quotient (HQ) for adult subpopulation exceeded unitary in seeds from nano-TiO treatments (HQ = 1.75 and 1.96, respectively) while no potential risk was obtained for leaves. Overall, foliar application of nano-TiO portends significant ameliorative potential for Cd toxicity in cowpea plants.
这项研究旨在探讨叶面施纳米 TiO2 对豇豆植株镉毒性的影响。豇豆植株在 10mg/kg 土壤中暴露于镉毒性 21 天后，随后进行了六次叶面施纳米 TiO2 干预。结果表明，与未受干预的镉胁迫植株相比，叶面喷施纳米 TiO2 后，叶绿素 b 和总叶绿素含量明显增加。有趣的是，与镉胁迫植株相比，纳米 TiO2 喷雾后根、茎和籽粒中的镉含量显著降低（p<0.05）。然而，干预后可食用组织（叶片和种子）中的镉含量仍高于推荐阈值。此外，纳米 TiO2 干预促进了根和叶中应激酶的活性，并增加了种子中锌、锰和钴的水平，与未受干预的镉胁迫植株相比。成人亚群从叶片和种子中摄入的镉估计每日摄入量超过了世界卫生组织推荐的每日摄入量的数倍，在镉胁迫和纳米 TiO2 处理的植株中。对于成人亚群，纳米 TiO2 处理的种子的健康风险商数（HQ）超过了 1（HQ=1.75 和 1.96，分别），而叶片则没有潜在风险。总的来说，叶面喷施纳米 TiO2 对豇豆植株的镉毒性具有显著的改善潜力。
