Heavy metals are major pollutants that pose threats to wetland environments. In the present study, surface sediments from wetlands vegetated by invasive species Spartina alterniflora in the Yellow River Delta were collected and determined for the mass fractions of Co, Ni, As, Cd and Pb. Results showed mass fractions of Co, Ni, As, Cd and Pb in the sediments of the S. alterniflora communities ranged from 8.5 to 16.0, 13.9–27.9, 3.2–13.8, 0.08–0.24, and 17.6–37.5 mg/kg dw, respectively, generally presenting an order of Pb > Ni > Co > As > Cd. The levels of heavy metals in sediments in the S. alterniflora communities were higher than those in the wetland vegetated by the native plant species Suaeda heteroptera. Correlations among metal elements were highly significant, suggesting that they might have the same sources. Clay and TOC were important factors affecting the spatial distribution of metals. The I_geo values of the investigated elements in the sediments were frequently lower than 0, revealing the slight pollution status of these metals. Relatively slight values of E_rⁱ and RI suggested that the potential ecological risks caused by the 5 metals were low. Our findings could provide a better understanding of the correlation between metal pollution and bio-invasion in wetland ecosystems.

Winter jujube (Ziziphus jujuba Mill. cv. Dongzao) is highly popular due to its attractive taste and flavor of fruits. However, its cultivation is facing a serious obstacle for the substantial decrease in fruit soluble solids contents. In this study, four commonly-used fertilization types, including organic manure application (OM), combined application of manure and NPK fertilizer (OC), NPK fertilizer application at high rate (HC) and NPK fertilizer application at low rate (LC) were selected to investigate their effects on soil and fruit properties. Results showed that fertilization influenced soil organic matter (SOM) and NPK contents. Fruit yield decreased as HC (3.37tha⁻¹) > OC (2.81tha⁻¹) > OM (2.14tha⁻¹) > LC (1.92tha⁻¹).Total soluble solids (TSS), protein contents, and the ratio of TSS to titratable acid (TA) were highest in OM, followed by OC, LC and HC. TSS and TSS/TA ratio in OM were 23.0% and 27.0% higher than those in HC. Fruit yield was significantly positively correlated with soil available N, vegetative shoot leaf N, and total topsoil P contents. TSS and TSS/TA ratio both significantly positively correlated with SOM of topsoil and leaf P contents. Combined application of organic and inorganic fertilizers should be the optimal mode for winter jujube production.

Parthenium hysterophorus L., as an invasive plant, has negatively impacted the ecosystem functioning and stability of the terrestrial ecosystem in China. However, little information was available for its effects on microorganisms in the Yellow River Delta (YRD), the biggest newly-formed wetland in China. In the present study, high-throughput sequencing technology was used to obtain the bacterial community in soils and roots of different plant species, including P. hysterophorus and some native ones in the YRD. Our results showed that the Proteobacteria, Acidobacteriota, Gemmatimonadota, and Actinobacteriota were dominant in the rhizosphere soils of P. hysterophorus (84.2%) and Setaria viridis (86.47%), and the bulk soils (80.7%). The Proteobacteria and Actinobacteriota were dominant within the root of P. hysterophorus. A total of 2468 bacterial OTUs were obtained from different groups among which 140 were observed in all the groups; 1019 OTUs were shared by P. hysterophorus non-rhizosphere soil bacteria (YNR) P. hysterophorus rhizosphere soil bacteria (YRR) groups. The indexes of the ACE (823.1), Chao1 (823.19), Simpson (0.9971), and Shannon (9.068) were the highest in the YRR groups, showing the greatest bacterial community diversity. Random forest analysis showed that the Methylomirabilota and Dadabacteria (at the phylum level) and the Sphingomonas, and Woeseia (at the genus level) were identified as the main predictors among different groups. The LEfSe results also showed the essential role of the Acidobacteriota in the YRR group. The SourceTracker analysis of the bacterial community of the YRR group was mainly from GBS groups (average 53.14%) and a small part was from YNR groups (average 6.56%), indicating that the P. hysterophorus invasion had a more significant effect on native plants’ rhizosphere microorganisms than soil microorganisms. Our observations could provide valuable information for understanding the bacterial diversity and structure of the soil to the invasion of P. hysterophorus.

In the present study, winter jujube organs including fruit, fruiting leaf and foliage leaf, and associated soils in 14 typical orchards in Binzhou City, Shandong Province, China were collected and determined for the mass fractions of Co, Ni, Cu, Zn, and Cd. The mass fractions of Co, Ni, Cu, Zn, and Cd in plant tissues generally showed an order of Cu > Zn > Ni > Co > Cd as well as those in the soils decreased as Zn > Cu > Ni > Co > Cd. The values of single factor index and Nemerow pollution index suggested the jujube fruits were not polluted by heavy metals. Values of estimated daily intake for all the elements were far below their associated acceptable reference values, indicating no health risks would be caused by a single trace element. The results of targeted hazard quotient (THQ) of the metals in the fruits decreased as Cu > Ni > Zn > Cd accompanying total THQ (TTHQ) lower than 1 showing no hazard would be caused by those metals. Correlation analysis showed soil might not be the main source of heavy metals in winter jujube organs. Bioaccumulation factors (BAFs) for Co, Ni, Zn and Cd in fruits and leaves were far below 1 suggesting their low bioavailablities. The relatively great BAFs of Cu in the leaves might be due to the application of fertilizers and pesticides containing great amounts of Cu through soil and foliar spraying. To sum up, heavy metals tended not to be a major threat to winter jujube cultivation, and winter jujube had great edible safety.

Magnesium (Mg) release (MGR) proteins play a crucial role in maintaining Mg²⁺ homeostasis in plant cells. However, MGR family genes have not yet been explored in crops. This study identified the wheat MGR (TaMGR) family members via BlastP alignment. A total of 15 MGR genes were mapped to 12 chromosomes. Cis-element prediction in the promoter region revealed that the ABA-responsive element (ABRE) was 100% conserved among all family members. Collinearity analysis indicates that MGR genes in monocot plants may have higher conservation compared to dicot plants. Expression profiling analyses uncovered the expression patterns of TaMGR genes across diverse tissues and under various stresses. Our results demonstrated that TaMGR5D and TaMGR5A.2 were significantly induced by both powdery mildew and stripe rust pathogen infections, whereas TaMGR4A transcript levels were upregulated in response to drought, heat and their combined stress. These findings indicate that TaMGRs may contribute coordinately to the regulation of wheat growth and development as well as adaptive responses to adverse conditions through member-specific expression patterns. This study systematically identified and analyzed the evolution and expression regulation characteristics of TaMGRs, providing a theoretical basis for in-depth research on the functional mechanisms of the TaMGRs and for improving the Mg use efficiency and stress adaptability of wheat via molecular approaches.