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In some mutualisms involving host plants, photoassimilates are provided as rewards to symbionts. Endophagous organisms often manipulate host plants to increase access to photoassimilates. Host manipulations by endophagous organisms that are also mutualists are poorly understood. We show host plant manipulations by symbionts and the role of phytohormones, i.e. the auxin indole-3-acetic acid (IAA), and the cytokinin trans-zeatin (tZ), in the brood-site pollination mutualism between fig trees and pollinator fig wasps. In this interaction, pollinator wasps pollinate Ficus flowers within an enclosed inflorescence called a syconium, in exchange for flowers that develop into galls nourishing pollinator offspring. To examine host manipulation by pollinator galls by affecting host fitness through seed reduction, we compared growth hormones released by syconial occupants within three experimentally produced treatment groups of syconia: S (containing only seeds), G (containing only pollinator galls) and SG (containing seeds and pollinator galls). We harvested syconia from each treatment in early and mid-phases of syconial maturation when maximal growth occurs and measured hormone levels. Hormones were reduced by mid-phase in general; however, their levels were mostly sustained in G syconia in the mid-phase, suggesting that galls manipulate the host to continuously access resources. We found no difference in IAA and tZ levels of S and G syconia. IAA concentrations were higher in SG syconia. From the perspective of the maintenance of mutualism, syconium volume and hormone concentrations were highest when both seeds and galls were present (SG treatment), indicating that both partners control allocation of resources to syconia. [ABSTRACT FROM AUTHOR]

• Isolation and characterization of the bacterial species. • Microorganism resistant to heavy metals was identified. • SEM and FTIR for identifying heavy metal remediation. • Bioremediation confirmation through seed germination studies. In this investigation, heavy metal-resistant microorganisms from tannery effluent were isolated, characterized, and identified. Also, to study their phytotoxicity towards Macrotyloma uniflorum. The characterized bacterium, identified as Stenotrophomonas rhizophila , showed different resistance levels and sensitivity to too many antibiotics tested. In the current investigation, nine aerobic strains of bacteria from the tannery effluent were identified. Based on the tests looked at, such as the lowest inhibitory concentration, the relatively heavy metal analysis showed the maximum percentage of degradation of Na 2 HAsO 4 was 91.6 %, Hg was 91 %, and Cr was 78.66 %, respectively. Furthermore, the IAA generation exhibited greater tolerance and stimulated plant development. The isolated bacteria showed MARI against the evaluated antibiotics at a rate of 30 %. On the other hand, the study found that inoculation with metal-tolerant bacteria dramatically enhanced plant growth and metal accumulation and protected plants from the damaging effects of heavy metals. The selected bacteria shield plants from the growth-inhibiting effects of heavy metals (Cd and Cr). According to these results, such metal-tolerant bacteria that promote plant growth are valuable resources exploited to create bio-inoculants that would increase the effectiveness of heavy metal removal. [Display omitted] [ABSTRACT FROM AUTHOR]

Previous research on cadmium (Cd) focused on toxicity, neglecting hormesis and its mechanisms. In this study, pakchoi seedlings exposed to varying soil Cd concentrations (CK, 5, 10, 20, 40 mg/kg) showed an inverted U-shaped growth trend (hormesis characteristics): As Cd concentration increases, biomass exhibited hormesis character (Cd5) and then disappear (Cd40). ROS levels rose in both Cd treatments, with Cd5 being intermediate between CK and Cd40. But Cd5 preserved cellular structure, unlike damaged Cd40, hinting ROS in Cd5 acted as signaling regulators. To clarify ROS controlled subsequent metabolic processes, a multi-omics study was conducted. The results revealed 143 DEGs and 793 DEMs across all Cd treatment. KEGG indicated among all Cd treatments, the functional differences encompass: "plant hormone signal transduction" and "starch and sucrose metabolism". Through further analysis, we found that under the influence of ROS, the expression of IAA synthesis and signaling-related genes was significantly up-regulated, especially under Cd5 treatment. This further facilitated the accumulation of reducing sugars, which provided more energy for plant growth. Our research results demonstrated the signaling pathway involving ROS-IAA-Sugar metabolism, thereby providing a novel theoretical basis for cultivating more heavy metal hyperaccumulator crops and achieving phytoremediation of contaminated soils., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)