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Strigolactone can improve the tolerance of plants to abiotic stress. To improve the phytoremediation capacity of cadmium (Cd) hyperaccumulator Galinsoga parviflora Cav., the effects of strigolactone (using strigolactone analog GR24 with the concentration of 1 and 2 μmol/L) on the Cd accumulation of G. parviflora were studied. Cd treatment at 0.1 mg/L inhibited the growth of G. parviflora. Under Cd stress (0.1 mg/L), GR24 had no significant effect on the biomass and catalase activity of G. parviflora, while it decreased the peroxidase activity and increased the superoxide dismutase activity. In addition, GR24 decreased the root Cd content and root Cd extraction. GR24 at 1 μmol/L increased the shoot Cd content, shoot Cd extraction, bioconcentration factor, and translocation factor, while at 2 μmol/L, the opposite effect was observed. When the concentration of GR24 was 1 μmol/L, the shoot Cd content and shoot Cd extraction increased by 8.75% and 12.35%, respectively, compared with control. Moreover, correlation and grey relational analyses showed that the translocation factor, shoot Cd content, and plant height were the top three most highly correlated parameters with the shoot Cd extraction. These findings suggest that GR24 at 1 μmol/L can improve the phytoremediation capacity of G. parviflora for Cd. [ABSTRACT FROM AUTHOR]

Cadmium (Cd)‐contaminated soil has affected the fruit production safety. To decrease the Cd accumulation in the fruits, the effects of intercropping with the potential Cd‐hyperaccumulator Solanum photeinocarpum and its post‐grafting generations on the Cd uptake in cherry (Cerasus pseudocerasus) were studied by the pot experiments. Intercropping increased the biomass of cherry seedlings to some extent, and decreased the biomass of S. photeinocarpum and its post‐grafting generations. Intercropping decreased the Cd contents in cherry seedlings, and increased the Cd contents in S. photeinocarpum and its post‐grafting generations. Compared with their respective monoculture, intercropping decreased the shoot Cd content in cherry seedlings by 31.37%–60.70%, and increased the shoot Cd contents in S. photeinocarpum its post‐grafting generations by 18.50%–28.76%. In addition, intercropping also decreased the root‐to‐shoot Cd translocations in both plant species, and decreased the Cd content in the branches and fruits of fruiting cherry trees and the Cd extractions of S. photeinocarpum and its post‐grafting generations. Therefore, intercropping with S. photeinocarpum and its post‐grafting generations can be used to reduce Cd accumulation in cherry for fruit production safety. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination of orchard soils is a global problem that has been increasing. To decrease the Cd accumulation in fruits, intercropping the orchard crops with hyperaccumulator plants has been used for soil remediation. A pot and a field experiment were conducted to study the effects of intercropping the potential Cd-hyperaccumulator Solanum photeinocarpum and its post-grafting generations with loquat (Eriobotrya japonica) on the growth and Cd uptake of these two plant species. In the pot experiment, intercropping improved the biomass, Cd content, Cd extraction, and root-to-shoot Cd translocation in both species. Intercropping increased the DNA methylation levels, antioxidant enzyme activity, and soluble protein content of loquat seedlings. These results indicate that intercropping could improve the phytoremediation of S. photeinocarpum and its post-grafting generations and increase the Cd uptake in loquat seedlings. In the field experiment, intercropping increased the Cd contents in the old branches, while it decreased that in the young branches and fruits of loquat. These findings indicate that intercropping could increase the Cd uptake in old tissues but reduce the Cd uptake in young tissues and fruits of loquat. So, intercropping loquat with S. photeinocarpum and its post-grafting generations could be used in Cd-contaminated orchards. Intercropping the potential Cd-hyperaccumulator Solanum photeinocarpum and its post-grafting generations with loquat mutually promoted the growth of two plant species, and also promoted the cadmium uptakes in S. photeinocarpum and old branches of loquat, while inhibited the Cd uptake in the loquat young tissues (young branches and fruits). These results are the new findings of the intercropping. [ABSTRACT FROM AUTHOR]

Nasturtium officinale is a cadmium (Cd) accumulator plant, but its phytoremediation capacity is low compared to other hyperaccumulators. To improve the phytoremediation capacity, the seedlings of N. officinale was grown in Cd-contaminated paddy soils, and the effects of diethyl aminoethyl hexanoate (DA-6) on N. officinale growth and Cd accumulation were studied. DA-6 increased the shoot biomass of N. officinale, and had a quadratic polynomial regression relationship with root and shoot biomass. DA-6 had no significant effects on chlorophyll a, chlorophyll b, and carotenoid contents, increased peroxidase, superoxide dismutase, and catalase activities, and decreased the soluble protein content. DA-6 also increased the Cd content and Cd extraction of N. officinale to some extent, and had a quadratic polynomial regression relationship with the root Cd content, shoot Cd content, root Cd extraction, and shoot Cd extraction. Significant correlations were found among plant biomass, chlorophyll content, Cd content, Cd extraction, and antioxidant enzyme activity. Furthermore, soluble protein content and soil exchangeable Cd was significantly correlated with plant Cd content and Cd extraction. Therefore, DA-6 can promote N. officinale growth and improve its phytoremediation capacity for Cd-contaminated paddy soils, with a recommend optimum dose of 20 mg/L. [ABSTRACT FROM AUTHOR]

To determine if the uniconazole concentration(s) whether could enhance the cadmium (Cd) tolerance of Cyphomandra betacea seedlings, the effects of spray treatments with various uniconazole concentrations (0, 5, 10, 20, and 50 mg/L) on the physiological characteristics and Cd accumulation of C. betacea seedlings were studied in a hydroponic experiment. The results indicated that uniconazole significantly decreased the Cd content of C. betacea seedling stems, leaves, and shoots, but significantly increased the biomass of all analyzed seedling parts. Additionally, the leaf chlorophyll a, chlorophyll b, and carotenoid contents as well as the net photosynthetic rate, transpiration rate, stomatal conductance, and CO2 concentration of intercellular were higher for the uniconazole‐treated C. betacea seedlings than for the control seedlings. The optimal uniconazole concentration significantly promoted the superoxide dismutase, peroxidase, and catalase activities and the soluble protein content of C. betacea leaves. Moreover, uniconazole decreased the soluble sugar content of the C. betacea roots and stems, but had the opposite effect on the soluble sugar content of the leaves and shoots. The 20 mg/L uniconazole treatment resulted in the highest C. betacea seedling biomass and the lowest Cd content, indicating this concentration may be useful for improving C. betacea seedling growth in Cd‐contaminated soils. [ABSTRACT FROM AUTHOR]