Plant Biomass Research Articles

Biochar and nanoscale silicon synergistically alleviate arsenic toxicity and enhance productivity in chili peppers (Capsicum annuum L.)

Arsenic (As) contamination in agricultural soils threatens crop productivity and food safety. In this study, we examined the efficacy of biochar (BC) and silicon nanoparticles (SiNPs) as environmentally sustainable soil amendments to alleviate As toxicity in chili (Capsicum annuum L.) plants. Our findings revealed that As stress severely inhibited the growth parameters of Capsicum annuum L., and subsequently reduced yield. However, the application of BC and SiNPs into the contaminated soil significantly reversed these negative effects, promoting plant length and biomass, particularly when applied together in a synergistic manner. Arsenic stress led to increased oxidative damage, as evidenced by a 29% increase in leaf malondialdehyde content as compared to the healthy plants. Nevertheless, the synergistic (BC + SiNPs) application effectively modulated antioxidant enzyme activity, resulting in a remarkable 55% and 66% enhancement in the superoxide dismutase and catalase levels, respectively, boosting chili's resistance against oxidative stress. Similarly, BC + SiNPs amendments improved photosynthesis by 52%, stomatal conductance by 39%, soluble sugars by 42%, and proteins by 30% as compared with those of control treatment. Additionally, the combined BC + SiNPs application significantly reduced root As content by 61% and straw As by 37% as compared with the control one. Transmission electron microscopy confirmed that the synergistic use of BC and SiNPs preserved chili leaf ultrastructure, shielding against As-induced damage. Overall, the supplementation of contaminated soil with BC and SiNPs was proved to be a sustainable strategy for mitigating As toxicity in chili peppers, enhancing plant growth, physiology, and yield, and thereby food safety.

The Multifunctional Anaphase Promoting Complex 7 (APC7) Gene Is Associated With Increased Plant Growth and Improved Resistance to DNA and RNA Viruses.

The anaphase promoting complex 7 (AtAPC7) is an APC/C subunit expressed in different organs of Arabidopsis thaliana and conserved among eukaryotes. A variant of the complete APC7 protein, containing its C-terminal region (named APC-CT), shows a high homology with a tobacco viral replication inhibitor (IVR-like) protein that reduces plant susceptibility to RNA viruses. Here, the role of the AtAPC7 gene was investigated by characterizing Arabidopsis plants overexpressing the full-length AtAPC7 (APC7OE) and the C-terminal portion (APC7-CTOE), by phenotypical, physiological and molecular approaches. APC7OE plants showed improved growth of vegetative organs, earlier flowering and increased photosynthetic efficiency, CO2 assimilation and productivity, compared with Col-0 control plants. Conversely, APC7-CTOE plants showed reduced susceptibility to both RNA and DNA viruses, along with an improvement in plant growth, although not surpassing APC7OE plants. Altogether, the data provide evidence for the role of the AtAPC7 in regulating cell division, expansion and differentiation, accompanied by an increase in photosynthetic capacity, resulting in enhanced plant biomass and seed yield. AtAPC7-CT might reduce growth-defence trade-offs, enabling plants to simultaneously defend themselves while promoting better growth. Our findings highlight the multifunctional role of AtAPC7, unveiling the potential of its orthologous genes as valuable biotechnological tools in important crops.

Enhanced remediation of acetochlor-contaminated soils using phosphate-modified biochar: Impacts on environmental fate, microbial communities, and plant health

Given that acetochlor (ACT) persists in soil for extended periods, disrupting microbial community structure and causing phytotoxicity to sensitive crops, this study investigated the potential of phosphate-modified biochar (PBC-800) to remediate ACT-contaminated soil. Incorporating 0.5 % PBC-800 into fluvo-aquic, red, and black soils increased their adsorption capacities by 80.4 mg g−1, 76.6 mg g−1, and 76.0 mg g−1, respectively. Even after six months of aging, the Kf values remained 1.6 to 5.1 times higher than in untreated soils. PBC-800 also accelerated ACT degradation across all three soil types, reducing residual ACT levels by 34.3 % to 76.4 % after 60 days, and shortening the degradation half-life by 5 to 7 days. High-throughput sequencing revealed that ACT reduced soil microbial diversity and disrupted community structure, while 0.5 % PBC-800 amendments promoted the growth of degradation-capable genera such as Rhodococcus, Lysobacter, and Gemmatimonas, enhancing microbial ecosystem stability. Furthermore, the amendment of soil with 0.5 % PBC-800 reduced ACT residue concentrations in maize and soybeans by 76.5 % to 82.9 %, and restored plant biomass, leaf chlorophyll content, and mesophyll cell ultrastructure to levels comparable to the control. Therefore, amending ACT-contaminated soil with PBC-800 mitigates ecological and environmental risks, boosts microbial activity, and safeguards plant health.

Reseeding increased plant biomass production and soil fertility, but not plant species diversity in degraded grasslands in China

Reseeding is a primary measure to restore degraded grasslands. Numerous studies have conducted experiments to investigate how the properties of grassland ecosystems respond to reseeding in China. However, there is a lack of summary of the results of these studies. Here, we conducted a hierarchical random-effects meta-analysis on the effects of reseeding on plant, soil, and microbial properties. We collected 19 variables, including plant biomass, species diversity and richness, soil organic carbon content, soil total and available nutrients, soil water content, soil microbial biomass and diversity, and enzyme activity, from a dataset of 1363 paired observations (degraded vs. reseeded) from 75 publications. The results showed that reseeding increased aboveground and belowground plant biomass by 70.2% and 68.0% on average, respectively. Reseeding increased soil organic carbon, phosphorus, and potassium contents, but did not affect soil nitrogen levels. Reseeding increased soil microbial nitrogen under conditions of tillage and fertilization. Reseeding age was found to have a positive correlation with species richness, while planting type, fertilization, and tillage did not have a significant impact on the species richness and diversity. Under the treatments of fertilization, non-tillage, and mix-planting, the response ratio of aboveground biomass to reseeding was positively correlated with the response ratio of species diversity to reseeding. Our results concluded that current reseeding practices can significantly improve plant biomass production and soil fertility but have minor effects on plant species diversity. These findings indicate that the preservation of biodiversity should receive greater attention from both researchers and practitioners in grassland remediation in China.

Mixed application of raw amino acid powder and Trichoderma harzianum fertilizer for the prevention and management of apple replant disease

Apple replant disease (ARD) is mainly caused by biological factors, and it severely restricts the development of the apple industry. The use of biological control measures to alleviate ARD is critically important for the sustainable development of the apple industry. The effects of raw amino acid powder and Trichoderma harzianum fertilizer on plant biomass, leaf and root indexes, soil physical and chemical properties, soil enzyme activity, and the soil fungal community were studied under pot and field conditions using Malus hupehensis Rehd. seedlings and grafted trees (Fuji New 2001/M9T337) as experimental materials. We found that the application of the materials significantly promoted plant growth, increased the leaf photosynthesis and chlorophyll content, root respiration rate, root antioxidant enzyme activity, and soil enzyme activity, significantly decreased the number of Fusarium sp. in soil, and significantly increased the abundance of beneficial bacteria. In conclusion, the mixed application of raw amino acid powder and Trichoderma harzianum fertilizer can is an effective method for the prevention and management of ARD.

Study on the enhancement effect of EDTA and oxalic acid on phytoremediation of Cr(VI) from soil using Datura stramonium L.

This study investigated the enhancing effects of soil treatment with ethylene diamine tetraacetic acid (EDTA) and oxalic acid (OA) on the remediation of Cr(VI) contaminated soil by Datura stramonium L. A greenhouse pot experiment was conducted, where Cr(VI) contaminated soil was treated with 100 mg/kg Cr(VI) and varying concentrations of EDTA (5 and 10 mmol/kg) and OA (5 and 10 mmol/kg). The effects of these soil treatments on biomass, chlorophyll content, antioxidant enzyme activities, and Cr(VI) enrichment and translocation efficiency of D. stramonium were evaluated. The results showed that added OA to soil significantly increased the biomass and chlorophyll content of D. stramonium. The addition of 10 mmol/kg of OA to soil increased the plant biomass by 67.16 % and chlorophyll b content by 40.01 %. In addition, OA soil treatment significantly enhanced the activities of superoxide dismutase (SOD) by 6.36 %, peroxidase (POD) by 163.13 %, catalase (CAT) by 36.92 %, and ascorbate peroxidase (APX) by 32.12 %, which effectively alleviated the oxidative stress induced by Cr(VI). In contrast, soil treatment with a high concentration of EDTA (10 mmol/kg) significantly reduced plant biomass and chlorophyll content, although it increased the biological concentration factor (BCF) of the stem and leaf, as well as the translocation factor (TF). In conclusion, appropriate amounts of EDTA and OA added to soil can enhance the phytoremediation efficiency of D. stramonium grown in Cr(VI) contaminated soil, with OA added to soil being more effective than addition of EDTA. This study revealed the potential mechanisms of chelating agents EDTA and OA in enhancing the phytoremediation of Cr(VI) contaminated soil by D. stramonium, providing a scientific basis for further optimization of phytoremediation techniques.

Production of cellulose nanocrystals from the waste banana (M. Oranta) tree rachis fiber as a reinforcement to fabricate useful bionanocomposite

It is crucial to produce CNCs from the waste biomass of secondary plants to reduce the extra pressure on primary plants which have other advantageous applications in many sectors. Whereas the useless banana (M. oranta) rachis after harvesting its edible part could be a very new and beneficial one. Meanwhile, several well-known methods could be conducted, namely water retting, scouring, alkali treatment, chlorite bleaching, and acid hydrolysis, to yield high-quality CNCs. The samples of all stages were characterized by several state-of-the-art techniques, namely FTIR-ATR, TGA, FESEM, XRD, UV-vis-NIR, DLS, and zeta potential analysis, for a better understanding of their structural properties/purity. However, obtained results recommended that the CNCs have shown extensive active edges, greater thermal improvement up to 700°C, high crystallinity around 81.07±0.15% with JCPDS-ICDD card number (00-056-1718), a honeycomb-like porous microstructure, and promising spherical shapes along with an average size around 50nm. Additionally, the newly produced CNCs were free from all impurities and coloring materials and revealed a higher negatively charged surface around -45mV. Therefore, due to these outstanding features, banana rachis CNCs with a high yield (around 82.05±0.06%) would be beneficially used as promising reinforcement to fabricate useful bionanocomposite for various applications to replace fossil-based hazardous synthetic materials.

Carbon isotope composition of biomass and water use efficiency in young plants of Jatropha curcas L. under irrigated or water deficit conditions

Jatropha curcas L. is a non-food crop quoted as a promising natural feedstock for biodiesel production in tropical and subtropical regions. Although an efficient mechanism of drought avoidance through stomatal control of transpiration has been demonstrated in this species, low carbon assimilation and growth rates preclude any advantage of such strategy under water limitation. Two greenhouse experiments were conducted with the objective of investigating varietal differences in water use as the trade-off between carbon isotope composition (δ13C) in different tissues and water use efficiency, in young plants of J. curcas. The first experiment was a survey with seven provenances of J. curcas under non-limiting water availability. There were no significant differences among provenances for leaf gas exchange rates, growth and whole-plant transpiration (T). However, significant effects of provenance and tissue (stem bark or leaf) in δ13C were demonstrated. The provenances CNPAE183 and CNPAE222 were selected for the second experiment, as variations in water use traits and δ13C between the two provenances were observed. Soil water deficit, imposed for 18 days, led to significant physiological, biochemical, and morphological changes. An early and sharp response to water deficit in CNPAE183 as compared to CNPAE222 was observed, as indicated by a 44% higher rate of decrease of T in the former. In addition, water deficit led to increase of δ13C, which was more pronounced in CNPAE222 (13% in young leaves) when compared to CNPAE183 (11% in young leaves). In both provenances, δ13C was less negative in young as compared to mature tissues. Significant and direct correlations between stem bark and leaf δ13C and leaf-level intrinsic water use efficiency were observed. Contrasting results, particularly on T and δ13C, suggest the existence of genetic diversity for water relations and metabolic traits linked to drought tolerance in J. curcas. Using stem bark or leaf δ13C measurements as the basis for large-scale screening of water-use efficient genotypes should be considered.

Developing Strategies to Mitigate Squash Injury from the Soil Residual Activity of Glyphosate in Bareground Systems

Fresh market vegetables are an essential component of the human diet. Maximizing yield is critical, and to achieve this goal, fields must be weed-free when vegetable crops are planted. Historically, removing emerged weeds just before planting has been accomplished using the herbicide glyphosate. However, recent research has indicated that glyphosate applied to sandy, low-organic-matter soils just before transplanting vegetables can be injurious. Two field experiments investigated 1) the response of transplanted squash to the residual activity of glyphosate, and 2) the effects of implementing tillage, irrigation, or extending the plant-back interval after application and before planting to mitigate injury from glyphosate. Glyphosate applied at 1.3, 2.5, or 3.8 kg ae/ha 1 day before transplanting injured squash 13%, 29%, and 53%, respectively; extending the interval between application and planting to 7 days reduced injury to 1%, 11%, and 28% at the same rates. An interaction between application rate and planting interval was also observed on squash plant widths and biomass, as well as early-season and total marketable fruit numbers and weights. Total marketable fruit number was reduced 29% and 52% by glyphosate at 2.5 or 3.8 kg ae/ha, respectively, and a reduction in fruit production of 36%, 28%, and 23% was observed when glyphosate was applied 1, 4, or 7 days before transplanting, respectively. In a separate study, light tillage (5 cm deep) was the most effective cultural practice evaluated because it eliminated damage by glyphosate. Overhead irrigation of 0.6 cm was not beneficial in mitigating injury by glyphosate. Recommendations from this research will help vegetable growers avoid injury from the residual activity of glyphosate through a FIFRA 2(ee) recommendation label.

Inoculation with multifunctional Bacillus sp. NEAU-DCB1-2 mitigates chromium toxicity in pakchoi (Brassica rapa ssp. chinensis) through a multi-level mechanism

Soil chromium (Cr) accumulation is escalating, severely hindering plant growth and development. Plant growth-promoting bacteria (PGPB) have shown potential in enhancing plant tolerance to heavy metals. However, the role and mechanisms of Cr(VI)-reducing PGPB strains in improving the growth of pakchoi under Cr toxicity remain unclear. This study aimed to isolate a Cr(VI)-reducing PGPB strain from Cr-contaminated soil, evaluate its effect on pakchoi growth under Cr(VI) stress, and investigate the mechanisms involved. Our findings showed that Bacillus sp. NEAU-DCB1-2 effectively reduce Cr(VI) to Cr(III) and produced indole-3-acetic acid and siderophores. Under Cr(VI) stress, inoculation with NEAU-DC1-2 significantly promoted seed germination and early growth of pakchoi. In pot experiments, NEAU-DCB1-2 significantly increased biomass accumulation, plant height, and root length of Cr(VI)-treated pakchoi seedlings, while reducing the Cr(VI) content in root, shoot and soil. Moreover, NEAU-DCB1-2 greatly increased catalase, superoxide dismutase, peroxidase, and ascorbate peroxidase activities in seedlings under Cr(VI) stress, thereby reducing malondialdehyde content. Transcriptome analysis indicated substantial alterations in gene expression patterns after inoculation with NEAU-DCB1-2 under Cr(VI) stress. Further analyses revealed that NEAU-DCB1-2 mainly affected the responses of antioxidant system, metal chelation and transport, together with auxin, abscisic acid, and jasmonic acid signaling to Cr(VI) stress. Conclusively, the Cr(VI)-reducing PGPB strain NEAU-DCB1-2 significantly enhances the growth and Cr tolerance of pakchoi through multiple mechanisms, offering a valuable microbial resource for mitigating the adverse effects of heavy metal contamination in agricultural soils on the yield and safety of vegetable crops.

Effect of Plant Identity in Wheat Mixtures on English Grain Aphid (Sitobion avenae) Control

ABSTRACTField experiments have demonstrated that wheat mixtures differ in their ability to regulate aphid populations. To further investigate the effectiveness of wheat mixtures (Triticum aestivum and Triticum turgidum) in controlling aphids, we conducted both laboratory and greenhouse experiments. Specifically, we assessed the associational resistance of two wheat mixtures (Florence‐Aurora with Forment, Florence‐Aurora with Montcada), and their respective monocultures, in different stages of the aphid host selection process. We analysed aphid acceptance rate, population growth, and load under different wheat treatments. Additionally, we characterised wheat aboveground biomass and nitrogen content as important functional traits for aphid resistant. Aphid acceptance decreased in plants of cv. Forment when exposed to volatiles from undamaged Florence‐Aurora plants, whereas the other tested combinations tested had no effect. Aphids performed differently in the two mixtures: Florence‐Aurora mixed with Forment significantly reduced aphid population growth and load compared to the monocultures, whereas the combination of Florence‐Aurora with Montcada wheat had no effect on aphid performance. The plant–plant interactions also modified the analysed traits. Nitrogen content of Florence‐Aurora wheat plants was reduced when mixed with Forment wheat, which may explain the lower aphid load observed in plants of cv. Florence‐Aurora when mixed with plants of cv. Forment. However, mixing wheats with similar aboveground biomass resulted in an increase in the average biomass of plants of both cultivars which could have led to a higher aphid population. The data supports the idea of right neighbour, as the benefits of wheat mixtures for aphid control were determined by the identity of the combined plants (or species). Finally, our results suggest that associating wheats with different traits may promote facilitative interactions, which in turn enhances associational resistance, whereas the combination of wheats with similar traits may result in competitive interactions that may hinder aphid control benefits.

Metagenomic analysis of a top-down enriched straw biodegradation synthetic bacterial consortium (StrBsyn) facilitates anaerobic rice straw degradation

Lignocellulose is a complex and recalcitrant component of plant biomass. Traditional sources of lignocellulose-degrading microorganisms are the rumen system of herbivores and soil microorganisms, with limited studies on marine sediments. In this study, we employed a "top-down" approach to construct a straw biodegradation synthetic bacterial consortium (StrBsyn) capable of degrading lignocellulose from offshore marine sediments. It achieved 66.74% cellulose, 63.79% hemicellulose, and 42.85% lignin conversion within 30 days using 0.2% rice straws. Additionally, the maximum concentrations of total organic carbon (TOC) and total volatile fatty acids (TVFA) reached 4.66g/mL and 15.10g/L, respectively, with a significant increase in pH. β-glucosidase, xylanase, laccase, and lignin peroxidase activities were detected in StrBsyn. Metagenomic sequencing revealed a dynamic shift in the community composition and functional genes. The taxonomic assignment of these functional genes suggested the genera Clostridium, Glomeromyces, and Sedimentobacter as major contributors to carbohydrate transport, metabolism, and lignin degradation processes. This study demonstrated the significant potential of harnessing the power of marine sediment microbial communities for sustainable and efficient anaerobic lignocellulose bioconversion.

Effect of In Vitro Pretreatment with Ag-Containing Amino Acid Nanofibers on Biometrics and Antioxidant Activity in Drought-Stressed Ex Vitro-Adapted Stevia rebaudiana Bertoni

Biotechnological methods prevent the destruction of natural populations of medicinal plants due to climate change and developing agriculture. This study evaluates the effects of in vitro pretreatment with two types of silver-containing amino acid nanofibers (NF-1%Ag and NF1-Ag salt) on the drought tolerance of ex vitro soil-adapted Steviia rebaudiana Bertoni. The duration of the drought was five days. The data suggested that the pretreatment with the studied nanofibers during plant propagation enhanced the plant tolerance to drought stress manifested in a smaller decrease in plant biomass accumulation and a smaller increase in sugar content. The pretreatment with the two tested nanoparticles of well-watered plants increased the leaf fresh biomass accumulation of the ex vitro-adapted S. rebaudiana compared to the untreated WW control plants. The highest values were reported at 10 mg L−1 NF1-Ag salt. Five days of drought led to a decrease in the leaf fresh biomass compared to the WW plants, with the recorded lowest reduction again at 10 mg L−1 NF1-Ag salt. These observations correlate with antioxidant activity improvement. The results show that adding 10 mg L−1 NF1-Ag salt to the MS medium led to higher ex vitro-adapted S. rebaudiana resistance to water deficit than 100 mg L−1. This paper discusses the impact of the selected nanofibers on parameters characterizing plant growth and antioxidant activity of drought-stressed ex vitro-adapted Stevia rebaudiana plants.

Citric acid-driven cadmium uptake and growth promotion mechanisms in Brassica napus

Citric acid (CA) is well-known for mitigating cadmium (Cd) toxicity in plants. Yet, the underlying mechanisms driving growth promotion, Cd detoxification/tolerance, and enhanced phytoremediation processes remain incompletely understood. This study investigated the effects of CA application (2.5 mM) on Brassica napus grown in Cd-contaminated (30 mg kg−1) growth medium through a controlled pot experiment. Cd exposure alone significantly impaired various plant physiological parameters in B. napus. Whereas CA application significantly (p < 0.05) enhanced physiological attributes, Cd detoxification and tolerance by modulating key genes involved in photosynthesis and Cd transport, including the metal-transporting P1B-type ATPases (Cd/zinc heavy metal-transporting ATPase 1; HMA1) and light-harvesting chlorophyll a/b-binding 3 (LHCB3). Notably, CA application increased Cd accumulation in stems and leaves by 4% and 35%, respectively, enhancing bioconcentration factors (BCF) by 12% in stems and 40% in leaves while reducing root BCF by 10%. This translocation was facilitated by the upregulation of HMA4, HMA2, and plant Cd resistance (PCR2) genes in plant leaves, improving Cd mobility within the plant. Furthermore, CA induced a 34% increase in phytochelatins and a 32% upregulation in metallothioneins, accompanied by a significant reduction in oxidative stress markers, including a 40% decrease in hydrogen peroxide and a 44% decline in malondialdehyde levels in leaves. Enhanced antioxidant enzyme activity and osmolyte accumulation further contributed to improved Cd detoxification/sequestration in leaves, reduced oxidative stress, and improved photosynthetic efficiency, resulting in enhanced plant biomass production and Cd tolerance. Transcriptomic analysis showed that CA treatment substantially influenced the expression of 12,291 differentially expressed genes (DEGs), with 750 common genes consistently downregulated in CK vs Cd treatment group but upregulated in Cd vs Cd-CA treatment group. Additionally, CA modulated 11 DEGs associated with 32 gene ontologies in the citrate pathway under Cd stress, highlighting its targeted regulatory effect on metabolic pathways involved in Cd stress response. This study offers novel insights into the synergistic role of CA in promoting plant growth and regulating Cd uptake in B. napus, highlighting its potential to enhance phytoremediation strategies.

Effect of viral-inoculation on the morphology, physiology, and phytochemistry of parsley (Petroselinum crispum)

Petroselinum crispum known as parsley is widely used in raw material food and culinary. In this study, the effects of three different viruses, parsley yellow leaf curl virus (PYLCV), sesame curly top virus (SeCTV), and cucumber mosaic virus (CMV), on parsley morphological, physiological, biochemical, and phytochemical characteristics, were investigated. To repeat the entire experiment, the study was conducted over two growing seasons using a completely randomized design. The results showed that all three viruses significantly reduced plant biomass, photosynthesis, greenness, and chlorophyll content. The Fv/Fm ratio, results revealed that PYLCV was more stress-inducing than SeCTV and CMV. Although PYLCV reduced essential oil (EO) content, SeCTV and CMV increased EO content. In addition to changes in all physiological and morphological parameters of parsley during virus-inoculation, the main component of parsley EO, myristicin, ranged from 37% to 73%. These results have profound implications for sustainable viral disease management, emphasizing the importance of understanding virus impacts on important plants to enhance crop resilience and ensure food quality and safety. This knowledge is crucial for optimizing phytochemical production and mitigating the effects of viral infections.

Sustainable control of invasive plants: Compost production, quality and effects on wheat germination

Invasive plant species pose significant ecological threats worldwide, affecting the stability and biodiversity of local ecosystems. As a result of their control, a considerable amount of plant biomass is produced, which can be used to produce various value-added products. Five different composts were prepared from three invasive plant species found in Latvia – Reynoutria japonica, Solidago canadensis, Lupinus polyphyllus. The stages of composting have been investigated and recommendations for process optimization have been made based on the quality characterization of the final compost. The quality of the prepared invasive plant biomass composts has been evaluated based on the main plant nutrient concentration, humic substance concentration, and mineral contents. The allelopathic lupin alkaloid concentration throughout the composting process has been evaluated and shows a consistent reduction. Obtained compost quality complies with the EU regulations for fertilizing products and soil amendments thus it can be considered equivalent to industrially produced compost and vermicompost. Seed germination tests confirm that compost prepared from invasive plants is suitable for plant growth and comparable to commercial composts. Based on pilot-scale composting results, recommendations for invasive plant composting have been suggested.

Native accumulator plants with a differential mercury phytoremediation potential in a region in Southern Amazon.

Mercury (Hg) is a non-essential trace metal, toxic to living beings and complex to quantify and mitigate in the environment. In this study, 25 plant species native to an Amazon-Cerrado transition area were tested for use in Hg remediation. Species identification, Hg quantification in plant biomass and soil at each sampling point, and evaluation of Hg compartmentalization in each plant were carried out. The results were subjected to statistical tests and evaluated using translocation coefficients (FT), bioconcentration (FBC), and bioaccumulation (FB). The results demonstrated that the distribution and accumulation of Hg differed between species and between the parts of the plant evaluated. Soil was the predominant source of Hg in the study area. The study highlighted seven species with Hg phytoremediation potential. Five translocator species were characterized, among these a preferentially bioaccumulating and bioconcentrating species, in addition to a bioconcentrating species and a preferentially bioconcentrating and bioaccumulating species of Hg. Potentially accumulating species stood out, Blechnum serrulatum Rich. (Blechnaceae), Mauritia flexuosa L.f. (Arecaceae), and Montrichardia arborescens (L.) Schott (Araceae), all widely distributed in tropical regions, characterized as rooted, terrestrial, or amphibious and associated with ruderal environments.

Russian thistle (Salsola tragus) ecology in wheat cropping systems of the Pacific Northwest

Abstract Russian thistle (Salsola tragus L.) is a significant summer annual weed in the semi-arid Pacific Northwest (PNW), causing yield losses of up to 50%. Understanding the biology and ecology of S. tragus is vital for developing effective integrated weed management (IWM) strategies. This study focused on 1) S. tragus emergence and seedbank persistence in two cropping systems: fallow–winter wheat (Triticum aestivum L.) and spring wheat–fallow–winter wheat rotations, and 2) S. tragus plant biomass and viable seed production in fallow and spring wheat fields. A four-year experiment (2020-2023) was conducted at the Columbia Basin Agriculture Research Center (CBARC) in Adams, OR, using a randomized block design with four replications. Salsola tragus seeds were sprinkled only at the beginning of the experiment, and seedling numbers were recorded throughout. Most seedlings emerged in the first year, with the highest rates in spring wheat (72%) and fallow (32%), followed by significantly lower rates (0.25-5%) in subsequent years. Seedling emergence began in late March and early April for the first two years but was delayed to May for the third year. Plant biomass and viable seed production were greater in fallow than in spring wheat, with early-season plants having more biomass than later-emerging plants. Plants emerged between early and mid-May produced the most viable seeds. Viable seed production was very low until it peaked in mid-September. Findings indicated that most S. tragus seedlings emerged in the first year after dispersal coinciding with spring precipitation and lasting approximately two months. Additionally, most S. tragus plants produce viable seeds in September, and seeds persist in the soil for more than two years. These results demonstrate the need for growers to control S. tragus emergence to prevent reinfestations and ultimately the need to control S. tragus plants before September to prevent the species from producing viable seed.

Techno-economic study for photovoltaic battery-free irrigation systems in an arid area for olive fields in Western West Al Minya, Egypt

Due to rain scarcity, artificial irrigation became an environmentally critical application for crop production. Proper irrigation is essential to maximize water use efficiency and plant biomass. Using clean energy sources is currently a trend that is sweeping the globe. To achieve this, we propose a solar-powered irrigation system. This study considers alternative irrigation systems using photovoltaic solar systems to pump water from deep wells for new land reclamation, whereas groundwater is the only source. The main objective is to evaluate various PV-powered pumping systems in Egypt's Western West Al Minya area. Two systems were nominated by considering the annual savings: the conventional irrigation Diesel system and a Photovoltaic (PV) battery-free irrigation system. The second system requires isolated pipes so solar radiation does not affect water temperature and avoids damage to plant roots. The 192 kW PV system was sized to operate a 60 KW water pumping system, with a required area of 1920 m2 for implementation. Direct irrigation using PV systems proved the best economical solution since it incurs the fewest costs of $0.015/m3 for 100–120 m well depth, compared with $0.073/m3 from the conventional system. As a result, the proposed PV-pumping system reduced the overall system cost by around 80% concerning the conventional system.

Growth and fecundity of Palmer amaranth escaping glufosinate in cotton with and without grass competition

Abstract Field experiments were conducted at Clayton and Rocky Mount, North Carolina, during the summer of 2020 to determine the growth and fecundity of Palmer amaranth plants that survived glufosinate with and without grass competition in cotton. Glufosinate (590 g ai ha-1) was applied to Palmer amaranth early postemergence (5 cm tall), mid postemergence (7 to 10 cm tall), and late postemergence (&gt;10 cm tall) and at orthogonal combinations of those timings. Non-treated Palmer amaranth was grown in weedy, weed-free in-crop (WFIC) and weed-free fallow (WFNC) conditions for comparisons. Palmer amaranth control decreased as larger plants were treated; no plants survived the sequential glufosinate applications in both experiments. The apical and circumferential growth of Palmer amaranth surviving glufosinate treatments was reduced by more than 44% compared to the WFIC and WFNC Palmer amaranth in both experiments. The biomass of Palmer amaranth plants surviving glufosinate was reduced by more than 62% when compared with the WFIC and WFNC in all experiments. The fecundity of Palmer amaranth surviving glufosinate treatments was reduced by more than 73% compared to WFNC Palmer amaranth in all experiments. Remarkably, the plants that survived glufosinate were fecund as WFIC plants only in the Grass Competition experiment. The results prove that despite decreased vegetative growth of Palmer amaranth surviving glufosinate treatment, plants remain fecund and can be fecund as non-treated plants in cotton. These results suggest that a glufosinate-treated grass weed may not have a significant interspecific competition effect on Palmer amaranth that survives glufosinate. Glufosinate should be applied to 5 to 7 cm Palmer amaranth to cease vegetative and reproductive capacities.