摘要：
Amaranthus spp. are a group of strongly invasive and vigorous plants, and heavy metal phytoremediation using alien invasive Amaranthus spp. has been a popular research topic. In this study, the bioconcentration factor (BCF) and translocation factor (TF) of Amaranthus spp. were evaluated, focusing on the accumulation potential of cadmium (Cd) and lead (Pb) by plants from three different zinc mining areas, namely Huayuan (HYX), Yueyang (LYX), and Liuyang (LYX). The HYX area has the most severe Cd contamination, while the LYX area has the most apparent Pb contamination. The results showed that Amaranthus spp. had a strong Cd and Pb enrichment capacity in low-polluted areas. To elucidate the underlying mechanisms, we used high-throughput sequencing of 16S rRNA and internal transcribed spacer (ITS) regions to analyze rhizosphere bacterial and fungal communities in three areas. The results showed significant differences in the structure, function, and composition of microbial communities and complex interactions between plants and their microbes. The correlation analysis revealed that some key microorganisms (e.g., Amycolatopsis, Bryobacterium, Sphingomonas, Flavobacterium, Agaricus, Nigrospora, Humicola) could regulate several soil factors such as soil pH, organic matter (OM), available nitrogen (AN), and available phosphorus (AP) to affect the heavy metal enrichment capacity of plants. Notably, some enzymes (e.g., P-type ATPases, Cysteine synthase, Catalase, Acid phosphatase) and genes (e.g., ZIP gene family, and ArsR, MerR, Fur, NikR transcription regulators) have been found to be involved in promoting Cd and Pb accumulation in Amaranthus spp. This study can provide new ideas for managing heavy metal-contaminated soils and new ways for the ecological resource utilization of invasive plants in phytoremediation.
摘要：
<jats:p>Allelopathy has been considered a good explanation for the successful invasion of some invasive plants. However, the real latitudinal and longitudinal allelopathic effects on native species have rarely been documented since many exotics have spread widely. We conducted a Petri dish experiment to determine the latitudinal and longitudinal allelopathic patterns of an invasive alligator weed (<jats:italic>Alternanthera philoxeroides</jats:italic>) on a common crop (<jats:italic>Lactuca sativa</jats:italic>) in China, and find what determines the allelopathic intensity. The results showed that the allelopathic effects of <jats:italic>A</jats:italic>. <jats:italic>philoxeroides</jats:italic> increased with the latitude while decreased with the longitude. This indicated that <jats:italic>A</jats:italic>. <jats:italic>philoxeroides</jats:italic> used its allelopathy to gain competitive advantages more in its recent invaded communities than that in its early invaded ones as <jats:italic>A</jats:italic>. <jats:italic>philoxeroides</jats:italic> is expanding from southeast China to northwest China. Furthermore, we found that the allelopathic intensity of <jats:italic>A</jats:italic>. <jats:italic>philoxeroide</jats:italic> was negatively correlated to the leaf contents of soluble carbohydrate (SC), carbon (C) and nitrogen (N), but that was positively correlated to the leaf contents of soluble protein (SP), free amino acids (FAA), plant polyphenol (PP), phosphorus (P) and potassium (K). These results suggested that the allelopathic intensity of <jats:italic>A</jats:italic>. <jats:italic>philoxeroide</jats:italic> was more determined by the limited P and K nutrients as well as the intermediate allelochemicals (SP, FAA, PP) rather than the unlimited C, N and SC. Thus, we can speculate that the negative or positive effects of plant aqueous extracts are a function of not only the extract concentrations but also the trade-offs between inhibition and promotion of all components in the extracts. Then we could reduce the allelopathic effects of <jats:italic>A</jats:italic>. <jats:italic>philoxeroide</jats:italic> by controlling the component contents in the plant tissues, by fertilization or other managements, especially in the plant recent invaded communities.</jats:p>
通讯机构：
[Yan-Hong Wang; Ji-Hui Wen] E;Ecology Department, College of Resources and Environment, Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>School of Forestry and Bio-technology, Zhejiang Agriculture & Forestry University, Hangzhou, 311300, China<&wdkj&>Ecology Department, College of Resources and Environment, Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Institute of Plant Protection, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
关键词：
Autotoxicity;Bacterium;Detoxification;Invasion;Advantage;Release;Decline;Over time
摘要：
Plant invasive success is attributed to invaders' ecological advantages over their native neighbors. However, increasing evidence suggests that these advantages are expected to attenuate over time because of natural enemy accumulation, ecological evolution of native species and autotoxicity. We determined how an invasive Ageratina adenophora could remain its competitive advantages over time by avoiding its autotoxicity. Our results highlighted that the autotoxicity of A. adenophora in its invaded soil was reduced by some microbes. Moreover, an autotoxic alle-lochemical, 2-coumaric acid glucoside, detected in the invaded soil, demonstrated distinctly autotoxic effects on its seed germination and seedling growth. However, the autotoxic effects were greatly alleviated by a bacterium Bacillus cereus, accumulated by A. adenophora. Further-more, the allelochemical could be almost completely degraded by B. cereus within 96 h. Accordingly, we speculate that A. adenophora could aggregate B. cereus to release its autotoxicity maintaining its competitive advantages over time.
作者机构：
[Zhou, Xiaoyun; Kuang, Yiwen] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Peoples R China.;[Su, Zhaohong; Su, ZH; Hu, Shiyu; Qin, Xiaoli; Cheng, Cong; Wang, Jiaqi; Li, Jian] Hunan Agr Univ, Coll Chem & Mat Sci, Changsha 410128, Peoples R China.;[Ou, Lihui; Ou, LH] Hunan Univ Arts & Sci, Coll Chem & Mat Engn, Changde 415000, Peoples R China.
通讯机构：
[Su, ZH ; Hu, SY; Ou, LH ] H;Hunan Agr Univ, Coll Chem & Mat Sci, Changsha 410128, Peoples R China.;Hunan Univ Arts & Sci, Coll Chem & Mat Engn, Changde 415000, Peoples R China.
关键词：
melamine;nanomonomer;prepolymerization and electropolymerization;nanocomposite;selective detection of dopamine and uric acid
摘要：
The formation process of carbon dots (CDs) is mostly polymerization; recently, studies on the polymerization of carbon families (graphene oxide and C60) have been receiving exciting attention. Herein, a protocol of prepolymerization and electropolymerization of monomer (melamine) and nanomonomer (CDs fixed melamine residues) was proposed to prepare a nanocomposite for selective dopamine (DA) and uric acid (UA) sensing. The nanomonomer was prepared by hydrothermal prepolymerization of melamine, and then the nanocomposite was formed in situ by electropolymerization of the CDs/carboxylated multiwalled carbon nanotubes (MWCNTs-COOH)-modified glassy carbon electrode (GCE) in KCl solution. Scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry were used to characterize the properties of the nanocomposite. Under optimal conditions, the electrochemical sensor shows selectivity and a wide linear range from 0.1 to 10 μM for DA and 0.1 to 200 μM for UA, with the detection limit of 0.023 and 0.064 μM (S/N = 3) in the presence of AA, respectively. In addition, the proposed sensor was also applied to selectively test DA and UA in the presence of 500 μmol/L AA in real samples with satisfactory recovery.
期刊：
Environmental Science and Pollution Research,2023年30(12):32337-32347 ISSN：0944-1344
通讯作者：
Pu Jia
作者机构：
[Li, Jin-tian; Cheng, Yizhi] Sun Yat Sen Univ, Sch Life Sci, Guangzhou 510275, Peoples R China.;[Li, Fenglin; Wu, Zhuo-hui; Wu, Guanxiong; Jia, Pu] South China Normal Univ, Sch Life Sci,Inst Ecol Sci, Guangdong Prov Key Lab Biotechnol Plant Dev, Guangzhou Key Lab Subtrop Biodivers & Biomonitori, Guangzhou 510631, Peoples R China.;[Ji, Zhihui; Wang, Chenggang; Xiao, Xiao; Cheng, Yizhi; Li, Jing] Hunan New World Sci & Technol Co Ltd, Zhuzhou 412000, Peoples R China.;[Bu, Xuan] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410000, Peoples R China.
通讯机构：
[Jia, Pu] I;Institute of Ecological Science, Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, People's Republic of China.
关键词：
Heavy metal;Microbial biomass;Enzyme activity;Compost;Biochar
摘要：
<jats:p>The shortage of land resources restricts the sustainable development of agricultural production. Multiple cropping has been widely used in Southern China, but whether the continuous planting will cause a decline in soil quality and crop yield is unclear. To test whether multiple cropping could increase grain yield, we investigated the farmlands with different cultivation years (10–20 years, 20–40 years, and &gt;40 years). Results showed that tobacco-rice multiple cropping rotation significantly increased soil pH, nitrogen nutrient content, and grain yield, and it increased the richness of the bacterial community. The farmland with 20–40 years of cultivation has the highest soil organic carbon (SOC), ammonium nitrogen, and grain yield, but there is no significant difference in the diversity and structure of the bacterial community in farmlands with different cultivation years. The molecular ecological network indicated that the stability of the bacterial community decreased across the cultivation years, which may result in a decline of farmland yields in multiple cropping system&gt; 40 years. The Acidobacteria members as the keystone taxa (Zi ≥ 2.5 or Pi ≥ 0.62) appeared in the tobacco-rice multiple cropping rotation farmlands, and the highest abundance of Acidobacteria was found in the farmland with the highest SOC and ammonium nitrogen content, suggesting Acidobacteria <jats:italic>Gp4, GP7, GP12</jats:italic>, and <jats:italic>GP17</jats:italic> are important taxa involved in the soil carbon and nitrogen cycle. Therefore, in this study, the multiple cropping systems for 20 years will not reduce the crop production potential, but they cannot last for more than 40 years. This study provides insights for ensuring soil quality and enhancing sustainable agricultural production capacity.</jats:p>
摘要：
Boehmeria nivea L. Gaud (Ramie) produces one of the longest natural fibers in nature. The bark of ramie mainly comprises of the phloem tissue of stem and is the raw material for fiber. Therefore, identifying the molecular regulation of phloem development is important for understanding of bast fiber biosynthesis and improvement of fiber quality in ramie. In this study, we collected top bud (TB), bark from internode elongating region (ER) and bark from internode fully elongated region (FER) from the ramie variety Zhongzhu No. 1. Histological study indicated that these samples contain phloem tissues at different developmental and maturation stages, with a higher degree of maturation of phloem tissue in FER. RNA sequencing (RNA-seq) was performed and de novo transcriptome was assembled. Unigenes and differentially expressed genes (DEGs) in these three samples were identified. The analysis of DEGs by using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed clear differences in gene expression between ER and FER. Some unigenes involved in secondary cell wall biosynthesis were up-regulated in both ER and FER, while unigenes for some cell wall components or cell wall modifications showed differential expression between ER and FER. In addition, the ethylene respond factors (ERFs) in the ethylene signaling pathway were up-regulated in FER, and ent-kaurenoic acid oxidase (KAO) and GA 20-oxidase (GA20ox) for gibberellins biosynthesis were up-regulated while GA 2-oxidase (GA2ox) for gibberellin inactivation was down-regulated in FER. Both morphological study and gene expression analysis supported a burst of phloem and vascular developmental processes during the fiber maturation in the ramie stem, and ethylene and gibberellin are likely to be involved in this process. Our findings provide novel insights into the phloem development and fiber maturation in ramie, which could be useful for fiber improvement in ramie and other fiber crops.
关键词：
captation du plomb;croissance racinaire;endophytes;lead uptake;root growth
摘要：
Endophytic bacteria are generally helpful for plant growth and protection. We isolated from tobacco seeds three Pseudomonas strains (K03, Y04, and N05) that could produce siderophores, indole-3-acetic acid, and 1-aminocyclopropane-1-carboxylate deaminase, fix nitrogen, dissolve phosphorus and potassium, and tolerate heavy metals. In pot experiments, the three isolated strains significantly promoted root growth and increased the root enzyme activity in Nicotiana tobacum K326. Furthermore, bacterial inoculations increased the proportion of residual lead (Pb) by 8.36%-51.63% and decreased the total Pb content by 3.28%-6.38% in the contaminated soil during tobacco planting, compared with uninoculated soils. An effective decrease in Pb content was also found in tobacco leaves with bacterial inoculations. K03 inoculation decreased the Pb content in the upper leaves by 49.80%, and Y04 inoculation had the best effect, decreasing the Pb content in the middle leaves by 70.12%. Additionally, soil pH and root activity had significant effects on transformation and translocation of Pb. The study suggested that in response to Pb pollution in soil, a reasonable application of endophytes (e.g., Pseudomonas) might be a promising approach in promoting tobacco growth and reducing Pb content in tobacco, while simultaneously enhancing Pb stabilization in soils.
通讯机构：
Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture & Forestry Sciences, Beijing, China
关键词：
ZmMs7;genetic male sterility;hybrid seed production;maize;nontransgenic progeny;transgenic maintainer line
关键词：
Crop morbidity;Biological control agents;Bacterial interactions;Bacterial diversity;Bacterial community structure
摘要：
Bacterial wilt, caused by Ralstonia solanacearum, occurs occasionally during tobacco planting and potentially brings huge economic losses in affected areas. Soil microbes in different management stages play important roles in influencing bacterial wilt incidence. Studies have focused on the impacts of species diversity and composition during cropping periods on disease morbidity; however, the effects of the soil bacterial biomass, species diversity, species succession, and population interactions on morbidity remain unclear during non-cropping periods. In this study, we explored the soil bacterial communities in the non-cropping winter fallow (WF) and cropping late growing (LG) periods under consecutive monoculture systems using 16S ribosomal RNA gene sequencing and qPCR and further analyzed their effects on tobacco bacterial wilt incidence. We found that the bacterial communities in the WF period were significantly different from those in the LG period based on detrended correspondence analysis and dissimilarity tests. Crop morbidity was significantly related to bacterial community structure and to the presence of some genera during WF and LG periods. These genera, such as Arthrobacter, Pseudomonas, Acidobacteria GP6, and Pasteuria, may be potential biological control agents for bacterial wilt. Further analysis indicated that low soil bacterial diversity during the WF period, decrease of bacterial interactions from the WF to LG periods, and low soil biomass during the LG period all have the potential to increase morbidity. In conclusion, an increase of soil bacterial diversity and control of some bacterial abundances in the WF period might be an effective approach in controlling bacterial wilt incidence.
关键词：
auxins;cytokinins;gibberellins;Gossypium hirsutum;iTRAQ;near-isogenic line
摘要：
Identifying important regulative elements and pathways related to dwarfism in cotton is a major challenge in cotton breeding. An isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics of the stem terminal buds from the upland cotton (Gossypium hirsutum L.) dwarf line LA-1 and high near-isogenic line LH-1 was performed. Moreover, the transcriptional expression of differentially-expressed proteins (DEPs) belonging to the phytohormone signal transduction, hormone biosynthesis, and ubiquitin system were analysed using the quantitative real-time polymerase chain reaction.. A total of 4 849 proteins were identified from LA-1 and LH-1, 697 of which showed differential accumulations. Most of the DEPs have catalytic, binding, and transporter activity and are involved in metabolism- and protein processing-related pathways. In particular, seven DEPs, including two gibberellin (GA) receptors, three cytokinin (CK) receptors, CK oxidase and CK-N-glucosyltransferase were up-regulated in LA-1, and gibberellin 20-oxidase was down-regulated in LA-1. Our results suggest that the DELLA-independent GA signalling pathway is the primary cause of dwarfism in LA-1 and indicate that cytokinin response element CRE1-2, gibberellininsensitive dwarf, cytokinin oxidase,and gibberellin 3-β-dioxygenase are potential indicators of dwarf cotton. The profiling of DEPs may offer a valuable resource for cotton breeding.
