Bacha Hamza, Hussain Anwar, Murad Waheed, Irshad Muhammad, Hamayun Muhammad, Al-Huqail Asma A, Iqbal Amjad, Ali Sajid
Department of Botany, Garden Campus, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan.
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Heliyon. 2024 Jul 31;10(15):e35501. doi: 10.1016/j.heliyon.2024.e35501. eCollection 2024 Aug 15.
The pervasive issue of heavy metal contamination in agricultural lands poses significant concerns and has wide-ranging implications for ecosystems. However, an encouraging solution lies in exploiting the potential of fungal endophytes to alleviate these detrimental effects. This study emphasized on improving the growth-promoting and chromium-alleviating capabilities of fungal endophytes, particularly strain SH20, through ultraviolet (UV) irradiation. Following UV treatment, SH20 exhibited significantly enhanced growth-promoting and chromium-alleviating capabilities in comparison to its non-irradiated counterpart. Distinctly, the UV-treated SH20 strain demonstrated an improved ability to accumulate and reduce toxic chromate in the soil, effectively addressing the growth constraints imposed by elevated chromium levels in L. The UV-irradiated SH20 variant boosted shoot length up to 3 times that of the control. Similarly, this fungal strain displayed a remarkable increase in the total fresh weight of the seedlings, recording nearly 17 times greater than the control. The isolate treated with UV light reduced the absorption of chromium by about 3 times in the roots, helping the young plants to grow well even when exposed to chromate stress. A drop in root colonization by the UV-treated strain further resulted in reduced chromate absorption by the roots. Also, the strain showed great skill in boosting the host's antioxidant defenses by reducing the buildup of harmful reactive oxygen species (ROS), increasing the removal of ROS, and improving the plant's antioxidant levels, including phenols and flavonoids. When the host plants were exposed to 25 ppm of Cr stress, the UV-irradiated variant SH 20 stimulated the production of flavonoids (246 μg/ml) and phenols (952 μg/ml) in comparison to the control (with 220 μg/ml of flavonoids and 919 μg/ml of phenols). In conclusion, this report highlights how exposing the strain SH20 to UV light has the potential to enhance its abilities to promote growth and bioremediate. This suggests a promising solution for addressing heavy metal contamination in agricultural lands.
农田中普遍存在的重金属污染问题引发了重大关注,并对生态系统产生了广泛影响。然而,一个令人鼓舞的解决方案是利用真菌内生菌的潜力来减轻这些有害影响。本研究着重通过紫外线(UV)照射提高真菌内生菌,特别是SH20菌株的促生长和减轻铬毒害的能力。经过紫外线处理后,与未照射的对照相比,SH20表现出显著增强的促生长和减轻铬毒害的能力。明显地,经紫外线处理的SH20菌株在积累和还原土壤中有毒铬酸盐方面能力有所提高,有效解决了高铬水平对黑麦草生长的限制。经紫外线照射的SH20变体使茎长增加到对照的3倍。同样,这种真菌菌株使幼苗的总鲜重显著增加,记录显示几乎比对照大17倍。经紫外线处理的分离物使根部对铬的吸收减少约3倍,即使在暴露于铬酸盐胁迫下也有助于幼苗良好生长。经紫外线处理的菌株根部定殖率下降,进一步导致根部对铬酸盐的吸收减少。此外,该菌株通过减少有害活性氧(ROS)的积累、增加ROS的清除以及提高植物的抗氧化水平(包括酚类和黄酮类),在增强宿主抗氧化防御方面表现出色。当宿主植物暴露于25 ppm的铬胁迫时,与对照(黄酮类为220 μg/ml,酚类为919 μg/ml)相比,经紫外线照射的变体SH 20刺激了黄酮类(246 μg/ml)和酚类(952 μg/ml)的产生。总之,本报告强调了将SH20菌株暴露于紫外线如何有可能增强其促进生长和生物修复的能力。这为解决农田重金属污染提出了一个有前景的解决方案。