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Hybrid giant Napier (HGN) grass was used to examine its phytoextraction potential for removing heavy metal(oid)s from contaminated tailings. Following a two-year cultivation of HGN, the amount of heavy metal(oid)s Zn, Mn, Cu, Pb, Cd, Cr and As removed ranged from 12% to 26% in the tailings and 16% to 74% in the control soil. The root distribution profile and chemical analysis of the plant in the growth media suggest that heavy metal was phytoextracted by fibrous roots, then transported from roots to shoots and stored to all parts of the plant including fibrous roots, tap roots, stem and leaves. Most of the heavy metal was stored in the plant's stem due to its high biomass, although the highest concentration of the metal occurred in the fibrous roots. The plants grown in the contaminated tailings were generally stunted compared to those in the control soil, due to heavy metal phytotoxicity. Less biomass was produced in the HGN planted in the contaminated tailings, which was less than 1/2 amount of biomass yielded in the control soil. The biomass has the potential to be used in energy production. The phytoextraction of heavy metal by the HGN in this study was attributed to the well-developed root systems in the plant which is capable of phytoaccumulating nutrients and heavy metals. Results suggest that HGN has good phytoextraction potential in removing heavy metal(oid)s from contaminated tailing wastes and producing biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biogas, methane, and acid-base indicators were considered concurrently in AD system. • The performance of the improved sparrow search algorithm is obviously enhanced. • ISSALSSVM can serve as a potential early warning and control model for AD system. Anaerobic digestion as an important means of organic waste treatment will play a key role in the realization of ecological civilization and the goal of double carbon. However, the instability of the system due to the high sensitivity to operating conditions restricts the economy and sustainability of the current commercial biogas projects in China. Machine learning as an early warning and control tool for many industrial systems is also applicable to anaerobic digestion systems. Existing studies focus on the biogas or methane yield prediction of the system, while there are few studies have considered the acid-bases indicators, which is crucial to the stability of the system. In this study, an improved sparrow search algorithm was developed, and after comparing its performance with selected optimization algorithms using CEC2017 test suite, combined with LSSVM, was applied to the prediction of eight different indicators of anaerobic systems, and eight datasets were validated. The results show that the optimization algorithm proposed in this study improves the performance of LSSVM and the model of ISSALSSVM shows excellent potential in the early warning and controlling of anaerobic digestion system. [ABSTRACT FROM AUTHOR]

Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation, and comparison of PPF (P. edulis Sims) and YPF (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina, and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes. Comparative analysis revealed 7.6∼8.1 million single nucleotide polymorphisms, 1 million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma, and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways, and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoid metabolites accumulated more in PPF. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases. Our findings revealed that certain TPS homologs in both YPF and PPF varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the 2 passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits. The annotated reference genomes from yellow and purple passion fruit identify candidate genes for terpene synthases that may account for differences in flavor and color between the 2 varieties. [ABSTRACT FROM AUTHOR]

Pectin is one of the constituents of the cell wall, distributed in the primary cell wall and middle lamella, affecting the rheological properties and the cell wall stickiness. Pectin methylesterase (PME) and pectin methylesterase inhibitor (PMEI) are the most important factors for modifying methyl esterification. In this study, 45 PMEI genes from rice (Oryza sativa L.) were screened by bioinformatics tools, and their structure, motifs, cis-acting elements in the promoter region, chromosomal distribution, gene duplication, and phylogenetic relationship were analyzed. Furthermore, CRISPR/Cas9 was used to edit the OsPMEI12 (LOC_Os03G01020) and two mutant pmei12 lines were obtained to explore the functions of OsPMEI in plant growth and development, and under cadmium (Cd) stress. Compared to wild type (WT) Nipponbare, the second inverted internodes of the mutant plants shortened significantly, resulting in the reduction in plant height at mature stage. The seed setting rate, and fresh and dry weights of the mutants were also decreased in mutant plants. In addition, the pectin methylation of pmei12 lines is decreased as expected, and the pectin content of the cell wall increased at both seedling and maturity stages; however, the cellulose and hemicellulose increased only at seedling stage. Interestingly, the growth of the pmei12 lines was better than the WT in both normal conditions and under two phytohormone (GA3 and NAA) treatments at seedling stage. Under Cd stress, the fresh and dry weights were increased in pmei12 lines. These results indicated that OsPMEI12 was involved in the regulation of methyl esterification during growth, affected cell wall composition and agronomic traits, and might play an important role in responses to phytohormones and stress. [ABSTRACT FROM AUTHOR]

The exploitation of mineral resources is very important for economic development, but disorderly exploitation poses a serious threat to the ecological environment. However, investigations on the advantages of plant species and environmental pollution in polluted mining areas are limited. Thus, a survey was conducted to evaluate the impacts of abandoned mines on the surrounding ecological environment along rivers in polluted areas and to determine the Arsenic (As) pollution status in soil and plants. The results showed that the soil and vegetation along the river in the survey area were seriously polluted by As. The total As content of the 15 samples was significantly greater than the national soil background value (GB 15618-2018), and degree of pollution was nonlinearly related to the distance from the mine source, R2 = 0.9844. B. bipinnata, P. vittata and B. nivea were predominant with degrees of dominance of 0.01–0.33, 0.05–0.11, and 0.06–0.14 respectively. The As enrichment capacities of Juncus and P. vittata were significantly greater than those of the other plants, while the bioaccumulation factors (BCFs) were 21.81 and 7.04, respectively. [Display omitted] • The As pollution status of plants and soil in mine polluted area was evaluated by comprehensive investigation. • The degree of soil pollution was found to have a non-linear relationship with the distance from the mine source, with a high correlation (R2 = 0.9844). • B. bipinnata, P. vittata and B. nivea are dominant species in As-contaminated soils. • Juncus and P. vittata were found to have significantly higher Arsenic (As) enrichment capacity compared to other plant species. [ABSTRACT FROM AUTHOR]

Enzymes with fructan exohydrolase (FEH) activity are present not only in fructan-synthesizing species but also in non-fructan plants. This has led to speculation about their functions in non-fructan species. Here, a cell wall invertase-related Zm-6&1-FEH2 with no "classical" invertase motif was identified in maize. Following heterologous expression in Pichia pastoris and in Nicotiana benthamiana leaves, the enzyme activity of recombinant Zm-6&1-FEH2 displays substrate specificity with respect to inulin and levan. Subcellular localization showed Zm-6&1-FEH2 exclusively localized in the apoplast, and its expression profile was strongly dependent on plant development and in response to drought and abscisic acid. Furthermore, formation of 1-kestotriose, an oligofructan, was detected in vivo and in vitro and could be hydrolyzed by Zm-6&1-FEH2. In summary, these results support that Zm-6&1-FEH2 enzyme from maize can degrade both inulin-type and levan-type fructans, and the implications of the co-existence of Zm-6&1-FEH2 and 1-kestotriose are discussed. [ABSTRACT FROM AUTHOR]

The lack of power resources leads to the rapid development of biomass power generation. Biomass power generation technology can not only rationally utilize biomass resources, but also alleviate energy crisis. But if this biomass ash is not handled properly, indiscriminate dumping can cause serious environmental problems such as dust, air and water pollution. The purpose of this study was to use the basic physical and chemical properties of biomass waste ash and biochar to evaluate the effects of mixed uses on soil pH、heavy metal remediation and plant growth. Plant growth was undertaken using ryegrass to examine the potential value of an ash-biochar mixture to ameliorate soil acidity and heavy metal pollution. The special fertilizer for rice was prepared by adding ammonium dihydrogen phosphate, potassium chloride, and urea to the ash and biochar. The results showed that the mixed use of ash and biochar could ameliorate soil acidification, reduce the absorption of cadmium and lead by the plants (43 % and 35 %, respectively), and promote plant growth. Determining of its total nutrients, soluble phosphorus, nitrate nitrogen, and particle size supported that it fell within the high concentration fertilizer range of the national standard for compound fertilizers. The special fertilizer can be used as high quality fertilizer to promote crop growth. In-depth research on the treatment and recycling of biomass power generation waste ash has an essential effect on reducing secondary environmental pollution and waste recycling.It can reduce random dumping, thereby reducing dust, air and water pollution. This was conducted to provide a reference for the preparation of soil amendments and to develop a better amendment and high-quality special fertilizer for rice with biomass waste ash and biochar. [Display omitted] • Ash and biochar addition increased soil pH and promoted plant growth. • Ash and biochar can inhibited cadmium uptake and lead by ryegrass. • Special fertilizers based on ash and biochar reach the quality fertilizer standards. • The special fertilizer improved soil fertility and rice growth. [ABSTRACT FROM AUTHOR]