AUTHOR=Mahmoodi Nazanin , Movahedi Zahra , Ghabooli Mehdi 

TITLE=Impact of Piriformospora indica on various characteristics of tomatoes during nickel nitrate stress under aeroponic and greenhouse conditions

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 13 - 2022

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.1091036

DOI=10.3389/fmicb.2022.1091036

ISSN=1664-302X

ABSTRACT=As an essential nutrient for plant growth, nickel (Ni) requirement is very low, and its augmented level causes environmental pollution and toxicity. Being a root endophytic fungus, Piriformospora indica (P. indica) can be in this way beneficial to many plants under stress and non-stress conditions, particularly in terms of their improved growth performance. P. indica, as evidenced, enhances tolerance and resistance in most plants once experiencing a range of stresses caused by biotic and abiotic factors; e.g., diseases and heavy metals. Against this background, the positive effects of P. indica on the tomato plants under Ni-induced stress (viz., 300, 600, and 900 mg L-1) were analyzed in three lab, greenhouse, and aeroponic experiments in this study. The growth traits of the tomato plants, such as root length (RL) and root dry weight (RDW), were accordingly found to be positively boosted in the cases treated with P. indica, as compared with the non-treated ones. Treating with P. indica also thwarted the negative effects of Ni on some biochemical traits, including anthocyanin (Anth), proline (Pro), catalase (CAT), and glutathione peroxidase (GPx), while significantly minimizing the adverse impacts of this heavy metal at different levels on hydrogen peroxide (H2O2). In spite of this, the Ni-stressed plants indicated much better traits in the presence of this fungus, compared with the non-treated ones, in most of the cases measured. Moreover, the photosynthetic pigments, i.e., chlorophyll a and b (Chl a & b) and carotenoid content (Carot) were significantly higher in the tomato plants treated with P. indica under high Ni-induced stress, as compared with the non-treated ones under non-Ni conditions, in which these pigments were low. The Pro production was further observed all through the P. indica inoculation, which could aid the treated plants to become Ni-stress-tolerant. Finally, the present study helped broaden the knowledge of utilizing P. indica symbiosis in inducing the tolerance of heavy metals, like Ni, in tomato plants, to meet the goals of sustainable agriculture.