Khan Mawra, Ahmed Shakil, Yasin Nasim Ahmad, Sardar Rehana, Hussaan Muhammad, Gaafar Abdel-Rhman Z, Haider Faish Ullah
Institute of Botany, University of the Punjab, Lahore 54590, Pakistan.
SSG RO-II Department, University of the Punjab, Lahore 54590, Pakistan.
Plants (Basel). 2023 Oct 11;12(20):3528. doi: 10.3390/plants12203528.
Brassinosteroids (BRs) influence a variety of physiological reactions and alleviate different biotic and abiotic stressors. Turnip seedlings were grown with the goal of further exploring and expanding their function in plants under abiotic stress, particularly under heavy metal toxicity (lead stress). This study's objective was to ascertain the role of applied 28-homobrassinolide (HBL) in reducing lead (Pb) stress in turnip plants. Turnip seeds treated with 1, 5, and 10 µM HBL and were grown-up in Pb-contaminated soil (300 mg kg). Lead accumulation reduces biomass, growth attributes, and various biochemical parameters, as well as increasing proline content. Seed germination, root and shoot growth, and gas exchange characteristics were enhanced via HBL treatment. Furthermore, Pb-stressed seedlings had decreased total soluble protein concentrations, photosynthetic pigments, nutrition, and phenol content. Nonetheless, HBL increased chlorophyll and chlorophyll levels in plant, resulting in increased photosynthesis. As a result, seeds treated with HBL2 (5 µM L) had higher nutritional contents (Mg, Zn, Na, and K). HBL2-treated seedlings had higher DPPH and metal tolerance indexes. This led to the conclusion that HBL2 effectively reduced Pb toxicity and improved resistance in lead-contaminated soil.
油菜素甾醇（BRs）影响多种生理反应，并减轻不同的生物和非生物胁迫。种植芜菁幼苗的目的是进一步探索和扩展其在非生物胁迫下，特别是在重金属毒性（铅胁迫）下在植物中的功能。本研究的目的是确定施用28-高油菜素内酯（HBL）在减轻芜菁植物铅（Pb）胁迫中的作用。用1、5和10μM HBL处理的芜菁种子在铅污染土壤（300 mg/kg）中生长。铅积累会降低生物量、生长特性和各种生化参数，并增加脯氨酸含量。通过HBL处理提高了种子萌发、根和茎的生长以及气体交换特性。此外，铅胁迫的幼苗总可溶性蛋白浓度、光合色素、营养物质和酚类含量降低。尽管如此，HBL增加了植物中的叶绿素a和叶绿素b水平，从而提高了光合作用。因此，用HBL2（5μM/L）处理的种子具有更高的营养含量（镁、锌、钠和钾）。经HBL2处理的幼苗具有更高的DPPH和金属耐受指数。由此得出结论，HBL2有效地降低了铅污染土壤中的铅毒性并提高了抗性。
