Glomus versiforme and intercropping with Sphagneticola calendulacea decrease Cd accumulation in maize.

Little information is available on the influence of the compound use of intercropping (IN) and arbuscular mycorrhizal fungus (AMF) on Cd accumulation and the expression of Cd transporter genes in two intercropped plants. A pot experiment was conducted to study the influences of IN and AMF-Glomus versiforme on growth and Cd uptake of two intercropped plants-maize and Cd hyperaccumulator Sphagneticola calendulacea, and the expression of Cd transporter genes in maize in Cd-polluted soils. IN, AMF and combined treatments of IN and AMF (IN + AMF) obviously improved biomass, photosynthesis and total antioxidant capacities of two plants. Moreover, single and compound treatments of IN and AMF evidently reduced Cd contents in maize, and the greatest decreases appeared in the compound treatment. However, Cd contents of S. calendulacea in IN, AMF and IN + AMF groups were notably improved. Furthermore, the single and compound treatments of IN and AMF significantly downregulated the expression levels of Nramp1, HMA1, ABCC1 and ABCC10 in roots and leaves, and the largest decreases were observed in the combined treatment. Our work first revealed that the combined use of IN and AMF appeared to have a synergistic effect on decreasing Cd content by downregulating the expression of Cd transporter genes in maize.

The effect of Funneliformis mosseae on the plant growth, Cd translocation and accumulation in the new Cd-hyperaccumulator Sphagneticola calendulacea.

The screening and identification of hyperaccumulators is the key to the phytoremediation of soils contaminated by heavy metal (HM). Arbuscular mycorrhizal fungus (AMF) can improve plant growth and tolerance to HM; therefore, AMF-assisted phytoextraction has been regarded as a potential technique for the remediation of HM-polluted soils. A greenhouse pot experiment was conducted to determine whether Sphagneticola calendulacea is a Cd-hyperaccumulator and to investigate the effect of the AMF-Funneliformis mosseae (FM) on plant growth and on the accumulation, subcellular distribution and chemical form of Cd in S. calendulacea grown in soils supplemented with different Cd levels. At 25, 50 and 100 mg Cd kg-1 level, S. calendulacea showed high Cd tolerance, the translocation factor and the bioconcentration factor exceeded 1, and accumulation of more than 100 mg Cd kg-1 was observed in the aboveground parts of the plant, meeting the requirements for a Cd-hyperaccumulator. Moreover, FM colonization significantly increased both biomasses and Cd concentration in S. calendulacea. After FM inoculation, the Cd concentrations and proportions increased in the cell walls, but exhibited no significant change in the organelles of the shoots. Meanwhile, FM symbiosis contributed to the conversion of Cd from highly toxic chemical forms (extracted by 80% ethanol and deionized water) to less toxic chemical forms (extracted by 1 M NaCl, 2% acetic acid, 0.6 M HCl) of Cd in the shoots. Overall, S. calendulacea is a typical Cd-hyperaccumulator, and FM symbiosis relieved the phytotoxicity of Cd and promoted plant growth and Cd accumulation, and thus greatly increasing the efficiency of phytoextraction for Cd-polluted soil. Our study provides a theoretical basis and application guidance for the remediation of Cd-contaminated soil by the symbiont of S. calendulacea with FM.

Divergence of Phyllosphere Microbial Community Assemblies and Components of Volatile Organic Compounds between the Invasive Sphagneticola trilobata, the Native Sphagneticola calendulacea and Their Hybrids, and Its Implications for Invasiveness.

Closely-related plant groups with distinct microbiomes, chemistries and ecological characteristics represent tractable models to explore mechanisms shaping species spread, competitive dynamics and community assembly at the interface of native and introduced ranges. We investigated phyllosphere microbial communities, volatile organic compound (VOC) compositions, and potential interactions among introduced S. trilobata, native S. calendulacea and their hybrid in South China. S. trilobata exhibited higher α diversity but significantly different community composition compared to the native and hybrid groups. However, S. calendulacea and the hybrid shared certain microbial taxa, suggesting potential gene flow or co-existence. The potent antimicrobial VOC profile of S. trilobata, including unique compounds like p-cymene (13.33%), likely contributes to its invasion success. The hybrid's intermediate microbial and VOC profiles suggest possible consequences for species distribution, genetic exchange, and community assembly in heterogeneous environments. This hybrid deserves further study as both an opportunity for and threat to diversity maintenance. These differentiating yet connected plant groups provide insight into ecological and evolutionary dynamics shaping microbiome structure, species co-occurrence and competitive outcomes during biological exchange and habitat transformation. An interdisciplinary approach combining chemical and microbial ecology may reveal mechanisms underlying community stability and change, informing management of species spread in a globalized world.

Determination of in vitro antioxidant activity and in vivo antineoplastic effects against Ehrlich ascites carcinoma of methanolic extract of Sphagneticola calendulacea (L.) Pruski.

BACKGROUND AND AIM: Sphagneticola calendulacea (L.) Pruski (S. calendulacea) is a well-known medicinal plant that is widely used in traditional medicine. This study was conducted to evaluate the antioxidant and antineoplastic properties of S. calendulacea leaf. EXPERIMENTAL PROCEDURE: Methanol was used as a solvent to prepare leaf extract from the dried leaf of S. calendulacea (MESL). We have evaluated the total phenolic and flavonoid contents of MESL, and using five different assays; we have also evaluated the antioxidant property of MESL. In vivo antineoplastic activity of MESL against Ehrlich ascites carcinoma (EAC) cells in experimental mice was also explored. RESULTS: The phytochemical analysis of MESL exhibited the total phenolic, and total flavonoid contents in the dry extracts were 32.86 mg/gm of gallic acid equivalent and 127.26 mg/gm of catechin equivalent, respectively. Moreover, MESL also showed promising scavenging activity in all assays (IC50 value ≥70.5 µg/mL). In the in vivo antineoplastic assay, MESL showed increased EAC cell death at the doses of 50 mg/kg and 100 mg/kg body weight. MESL administration also induced apoptosis of EAC cells, significantly inhibited EAC cell growth, and increased the life span of EAC cell-bearing mice compared to EAC cell-bearing control mice. CONCLUSIONS: All findings of this study suggest potential antioxidant and antineoplastic properties of MESL.