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Conservation of trees which belong to renewable natural resources in developing countries through judicious utilization in building industry has been seriously left unattended to over the years. The utilization of this unprocessed wealth materials which could serve as one of the alternative constituents in construction materials is now a global concern. Therefore, the needs to investigate the strength and water sorption property of wood waste as a partial replacing material in brick production for building construction arise. Sawdust, sand and cement were mixed together at three different mixing ratios of 1 : 1 : 1, 1 : 1 : 2 and 1 : 1 : 3. The brick samples were replicated three times and subjected to water absorption, density and compressive strength tests. The results show that the effect of the equal volume of sand and sawdust with a subsequent increase in the cement portion at each mixing ratio level gave compact bricks without sudden fracture, reduced unit weight of bricks and subsequent lower water sorption properties of the bricks. The bricks show potentials to be used for wall partitioning. The introduction of sawdust also serves as partial sand replacement in concrete brick making.

The use of independent variables in volumetric modelling is an important step in fitting models to represent tree or stand characteristics. The DBH measured at 1.3 m from the ground level and total tree height (Ht) are the most commonly used independent variables when modelling individual tree volumes. This work aimed to analyze the importance of independent variables in fitting and selecting volumetric equations. A total of 750 trees from an experiment with three Eucalyptus spp. clones planted in five spacings in the semi-arid region of Pernambuco were used. Four statistical procedures were applied to compare the equations: Adjusted Fit Index (AFI), Akaike information criterion (AIC), mean absolute percentage error (MAPE), and a completely random design having the real tree volume as control and the fit equations as treatments. The error measuring heights in the field (EH) was also analyzed. Four heights were evaluated: Ht, height estimated in the field (He) and heights adjusted (Ha) from hypsometric relationships using the DBH [Ha (a)] and D_1.7 [Ha (b)], which was the diameter most correlated with the volume. The result indicates that all 18 fitted models provided high precision volumetric equations which do not differ at the 5% significance level.

Tanymecus dilaticollis is an important pest of maize and sunflowers in eastern Europe. In the present study, we examined the effectiveness of two commercially available bioinsecticides against T. dilaticollis adults under laboratory conditions: Naturalis^® based on the Beauveria bassiana fungus and an azadirachtin-based botanical product NeemAzal T/S^®. Our results suggested that adults of the pests are more susceptible to B. bassiana than to azadirachtin. Naturalis^®, tested at six concentrations (2.3 × 10² - 2.3 × 10⁷ conidia/mL), showed a high lethal effect to T. dilaticollis adults, and 100% corrected mortality was observed in the treatments over 2.3 × 10⁵ conidia/mL and 2.3 × 10⁶ conidia/mL for females and males, respectively. NeemAzal T/S^®, tested at four concentrations (0.5, 1, 2 and 4%) with two treatments, caused generally low to moderate mortality - 6-44% within 16 days. A field experiment consisted of two sprayings of maize experimental plots with Naturalis^® at a rate of 200 mL/0.1 ha and then the recording the number of dead adults of T. dilaticollis in the treated and control plots was conducted in north-western Bulgaria. Twenty days after treatment, a significantly higher mean mortality of the pest caused by the mycoinsecticide than in the control variants was registered.

The oomycete Phytophthora infestans is responsible for the disease known as late blight in potato and tomato. It is the plant pathogen that has caused the greatest impact on humankind so far and, despite all the studies that have been made, it remains the most important in this crop. In Spain during the last years a greater severity of the disease has been observed in both, potato and tomato, probably due to genetic changes in pathogen populations described recently. The aim of this study was the characterization of the physiological strains of 52 isolates of P. infestans obtained in different potato-growing areas in Spain. For this purpose, inoculations on detached leaves were performed in order to determine compatibility or incompatibility reactions. A total of 17 physiological races were found. The less frequent virulence factors were Avr5 and Avr8. By studying the epidemiology of the pathogen, a specific breeding program for late blight resistance can be implemented.

Irrational use of chemical method for crop protection, presents increasingly serious risks for human health and the environment. Droplet size and meteorological parameters are key factors to both environmental contamination and pest control efficacy. The objective of this study is to assess the impact of the nozzle use parameters, the operating pressure and the wind speed on droplet foliage deposition (retention) and soil deposition (losses), when treating artichoke. Several combinations were tested in a wind tunnel and in the field, under Mediterranean microclimatic conditions, using a fluorescent dye as a substitute for pesticide. Multiple regression models were built from tunnel data to predict foliage deposition and soil deposits, with determination coefficients of 0.96. Thus, models are able to simulate pesticide deposition on artichoke leaves and soil deposition, depending on sprayer parameters and wind speed. Foliage deposition and soil deposits rates ranged from 30 to 52% and 26 to 57% respectively for anti-drift nozzle. For conventional nozzle, rates varied from 20 to 38% and 31 to 62%. To improve retention and reduce spray losses, it is recommended to choose a medium droplet size when using an anti-drift nozzle, in conjunction with medium nozzle size, medium pressure and reduced wind speed.

Prof. Ing. Karel Veverka, DrSc. was an important figure in Czech agricultural phytopathology at the turn of the 20th and 21st centuries. His long, diverse experiences in the field of plant protection, combined with his excellent public speaking skills, led him to be recognized as one of the erudite experts of his time. His skillful presentations were widely appreciated at scientific conferences and seminars and at university lectures for students. All his scientific life, he kept contacts in the broader world of agricultural production, to which he was very close due to his personal experience. His expertise in chemical plant-protection products was unsurpassed. Beyond his own research and teaching activities, he always found time for the popularization of science. He published his achievements in both scientific journals and the popular-scientific press, being the author of numerous publications on plant protection, pesticides, the spread of fungal pathogens, diagnostics, and monitoring and epidemiology of phytopathogenic fungi.

Uneven distribution of precipitation and overexploitation of groundwater resources threatens the sustainability of agriculture in the North China Plain. Adoption of water deficit-tolerant winter wheat genotypes coupled with timely, adequate farming practice is crucial to enhance sustainable crop production and water productivity in the region. The present study aimed to evaluate water consumption patterns and water productivity of two winter wheat genotypes (Tainong-18 and Jimai-22), under no-tillage or conventional tillage, over a period of four consecutive cropping seasons. Under no-tillage, Tainong-18 showed the lowest soil moisture consumption before sowing in the 30-110 cm soil profile. Jimai-22 under conventional tillage and Tainong-18 under no-tillage showed the highest and lowest evapotranspiration across cropping seasons, respectively. Compared with conventional tillage, no-tillage reduced grain yield and water productivity of winter wheat, and the difference between them increased for grain yield (6.79, 11.99, 14.78, and 15.73%) and water productivity (0.99, 8.14, 12.18, and 13.30%) over the 2015-2016, 2016-2017, 2017-2018, and 2018-2019 cropping seasons, respectively. In contrast, Tainong-18 showed lower evapotranspiration and increased grain yield and water productivity compared with Jimai-22. Further, Tainong-18 showed a compensatory effect on the reduction of water productivity under no-tillage, compared with Jimai-22. Our conclusions indicate that the combination of no-tillage and water-efficient winter wheat genotypes is an effective strategy to offset the reduction in water productivity caused by no-tillage and thus maximise water productivity in the North China Plain.

The present study used various amounts of P-arsanilic acid (AsA) in pot experiments to evaluate the effects of AsA on arsenic (As) accumulation, speciation and meanwhile using the in vitro digestion/Caco-2 cell model to evaluate the bioavailability of As in rice. The results indicated a linear relationship between As in rice and As in soil, and at 75 mg AsA/kg of soil, As content in rice exceeded the statutory permissible limit of 0.2 mg As/kg dry weight in China. Speciation studies indicated that inorganic As (Asi), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) were the main As species in rice. Bioavailability of As experiment indicated that As uptake and transport amount by Caco-2 cells increased with increasing As accumulation in rice. In general, the content of AsA in soil reached or exceeded 75 mg/kg, which is not suitable for growing rice.

Zero-valent iron (ZVI) and rice husk (RH) have potential as adsorbents for heavy metals; however, their effects on iron plaque formation and heavy metal uptake by plants are still unclear. In this study, the impacts of ZVI, RH and their combinations on iron plaque formation on the root surface and the uptake of As and Cd by rice plants were investigated. A pot experiment was performed under waterlogged conditions using As^(III)- or Cd^(II)-spiked soil. The results showed that ZVI (0.05% or 0.2%) with or without RH significantly increased iron plaque formation and Fe contents in rice plants and pore water. Under As treatment, ZVI (0.05% or 0.2%) without or with RH obviously increased the As content in plaques and reduced the As content in grains by 67% and 66% and 19% and 24%, respectively. The Cd content was markedly increased in iron plaques and reduced in roots, shoots and grains by ZVI and RH. ZVI (0.05% or 0.2%), RH and their combinations reduced the grain Cd content by 61, 62, 60, 68 and 69%. These findings suggest that ZVI is effective in hindering As and Cd uptake by rice with or without RH in paddies contaminated with As or Cd.

This research had two main aims. First, to analyse the degradation dynamics of herbicides commonly used in carrot (aclonifen, clomazone, flufenacet, linuron, metribuzin, pendimethalin, S-metolachlor). Second, to compare the amount of herbicide residues with the maximum residue level and with requirements of non-residual production. The field experiments were conducted in 2012-2016. All tested herbicides resulted in relatively low concentrations of residues in carrot roots (up to 10 µg/kg) when the recommended withdrawal period was followed between application and harvest. The concentration of S-metolachlor in carrot roots exceeded the maximal residual limit (MRL) if the application was carried out four days before harvest. The measured values of other tested herbicide residues in carrot roots did not exceed the MRL in any of the tested samples. Pre-emergent use of clomazone, linuron and flufenacet could be recommended for non-residue carrot production. Post-emergent use of metribuzin can be used for non-residue carrot production if the interval between application and harvest is at least 80 days. Concentrations of herbicide residues in carrot leaves were many times higher than in roots. All tested herbicides can be applied for safe carrot production if applicators adhere to the requirements for use.

The article presents the effect of three sowing dates on the growth, development and yielding of four soybean cultivars of different earliness and under different temperature and precipitation conditions across the years. The seed yield from early sowing significantly correlated with the total precipitation in June and July, and at later dates, also with the total precipitation in August. The significantly highest soybean yields were collected from the sowing at a turn of April and May, and the highest seed and protein yield, as well as protein content in seed, were recorded for the mid-early Merlin cultivar. Neither the number and the seed weight per pod nor the 1 000-seed weight significantly depended on the sowing date. Over years, a significant, almost linear decrease in the plant height and the first pod setting height, the weight of nodules, the protein yield and the LAI (leaf area index) value was observed. High significant correlations were found between the seed yield and the plant height and the first pod setting height, as well as between the seed number and the seed weight per pod and the 1 000-seed weight as well as between the plant height and the first pod setting height.

The paper presents species richness and composition of arable weed vegetation in the region of West Bohemia (Czech Republic) in different types of farming (conventional and organic) and grown crops (winter and spring cereals, wide-row crops). During the field survey in the years 2007 to 2017, 105 phytocoenological relevés were recorded. The average species richness in one relevé was significantly higher in organic farming, as well as total weed cover. The lowest species richness was found in wide-row crops. Recently widespread species belonged to the most frequent species in our study. Based on multivariate statistics, the effects of variables on the occurrence of weed species were found as statistically significant. Most of the variability in data was explained by crop, following by type of farming. Weed species of Fabaceae Lindl. family (especially Vicia L.) and many perennial species positively correlated with the organic type of farming. Endangered species were found mainly in organic farming and cereals. Less intensive cultivation with a higher weed cover is beneficial for the promotion of biodiversity.

The use of cannabis for medicinal purposes dates back well before the era of modern medicine, but in recent years research into the use of medical cannabis in the medical and pharmaceutical sciences has grown significantly. In European countries, most cannabis plants have been and still are grown for industrial purposes. For this reason, hemp cultivation technology is relatively well researched, while little is known about the key factors affecting cannabis cultivation for medical purposes. The active substances of cannabis plant targeted by this review are called phytocannabinoids. The biosynthesis of phytocannabinoids is relatively well understood, but the specific environmental factors that influence the type and number of phytocannabinoids have been much less studied. Indoor or greenhouse cultivation, which uses automated lighting, ventilation, irrigation systems and complex plant nutrition has become much more sophisticated and appears to be the most effective method for producing medical cannabis. There are many different cultivation systems for cannabis plants, but one of the essential elements of the process is an optimal plant nutrition and selection of fertilisers to achieve it. This review summarises the existing knowledge about phytocannabinoid biosynthesis and the conditions suitable for growing plants as sources of medical cannabis. This review also attempts to delineate how nutrient type and bioavailability influences the synthesis and accumulation of specific phytocannabinoids based on contemporary knowledge of the topic.

Phosphorus (P) deficiency may trigger rhizodeposition, including protons and organic compounds, with possible effects on metal solubility and speciation. To explore the relevance of this process, we investigated biogeochemical changes in the rhizosphere of P-deficient canola (Brassica napus L.) and corn (Zea mays L.) cultivars grown in a pot experiment on calcareous soil. Depletion of total soluble (0.005 mol/L Ca(NO3)2-extractable) P in the rhizosphere varied with crop species and cultivar but was generally strong and negatively correlated with dissolved organic carbon (DOC) in canola (R2 = 0.868) and corn (R2 = 0.844) rhizospheres, indicating rhizodeposition in response to limited P availability. DOC was correlated with dissolved Cu, explaining 86% of its variation in the rhizosphere and bulk soil solution of canola and corn cultivars, respectively, suggesting Cu mobilisation via the formation of Cu-organic complexes. In line with lower Zn-organic complex stabilities, the effect of rhizodeposition was less pronounced for Zn mobilisation. We show that the P nutritional status of plants and the related variation of rhizodeposition among crops and cultivars represents a major control of metal solubility in soil, with possible effects on micronutrient supply and toxicity. Hence, targeted P availability control should be considered in the management of polluted and micronutrient-deficient soils.

Enhanced seeds, e.g. dressed, encrusted or pelleted seeds, are often sown in agricultural practice. These treatments play a different role depending on the type and chemical composition of the preparation. The aim of the experiment was to compare the effectiveness of three coatings (B - chitosan, C - chitosan + alginate/jojoba oil/E and D - chitosan + alginate/PEG) applied to soybean seeds in comparison to control (A). The study was carried out in three cultivars: Annushka, Mavka and Smuglyanka. The coatings did not differentiate seed yield in 2018 due to favourable weather conditions. The use of coating D in the following years increased seed yield by 0.46 t/ha in 2019 and by 0.51 t/ha in 2020 compared to control. The obtained results allow concluding that coating D was the most effective in soybean cultivation. The field emergence capacity, plant density as well as the SPAD (soil plant analysis development) and LAI (leaf area index) indices were significantly increased compared to control as a result of this coating application. The g_s index (stomatal leaf conductance) was significantly reduced. The cv. Smuglyanka yields were significantly higher compared to cvs. Mavka and Annushka, by 0.32 t/ha and 0.85 t/ha, respectively. The difference in seed yield between 2018 and 2019 was 0.81 t/ha.

High temperature is a limiting factor in the seed germination of most crops. This study evaluated the effects of hydropriming at 6, 12 and 18 h on germination performance and seedling establishment of sunflower seeds under high air temperature. Results showed that germination of unprimed seeds was suppressed at an average elevated temperature of 44.3 °C (range of 39.3 °C to 53.3 °C) for eighteen days indicated by an increased lag time to onset of germination and decreased germination percentage. Conversely, priming seeds for 12 h to 18 h increased the germination percentage, time to 50% seedling emergence (T₅₀), germination index and vigour index. Seedlings emerging from primed seeds exhibited uniform 16-day old seedlings (18 days after sowing), leading to greater seedling dry weight and shoot length as compared to unprimed seeds. Conversely, the total chlorophyll content remain unchanged for all seeds. The significant increase in the shoot parameters suggested a positive association with priming and stress tolerance. The priming duration of 12 h to 18 h showed improvement at elevated air temperature through the reduction of ungerminated seeds and increase in seedling growth characteristics.

Legislation limits for risk elements (As, Be, Cd, Co, Cr, Cu, Ni, Pb, V, Zn) in agricultural soil in the Czech Republic are given for the content of elements extracted by aqua regia. This extraction is time consuming and environmentally unfriendly. The regular soil survey is based on Mehlich 3 universal soil extractant and covers the simultaneous determination of macronutrients, sulphur, and micronutrients by inductively coupled plasma optical emission spectrometry (ICP-OES). Our study focused on the possibility to use Mehlich 3 extractant also for preliminary screening for the determination of the risk elements simultaneously with the other elements by the ICP-OES method. Mehlich 3 was confirmed as a reliable screening method for Cd regarding sensitivity, specificity and precision (> 0.8) when the cut-off value of 0.27 mg/kg in Mehlich 3 extracts was used for the prediction of soils to be above or below the legislation limit, which in turn is based on aqua regia extraction. Very good results were obtained for Be and promising results were received for As, Cu and V. But the available data were not sufficient for the determination of reliable cut-off values for Co, Cr, Ni, Pb and Zn.

Adequate nutrition of sugar beet with magnesium (Mg) and sulfur (S) has been assumed to be the key to increase fertiliser nitrogen (N) efficiency. This hypothesis was validated on two soils differing in textural class, i.e., sandy and loamy. The experiment consisted of three factors: (1) in-soil application of Kieserite (0, 24 kg Mg/ha); (2) foliar application of Epsom salt (0.2 kg Mg/ha); (3) N rates (0, 40, 80, 120, 160 and 200 kg N/ha). The following parameters were evaluated: (i) yield of storage roots (TY); (ii) qualitative features of storage roots, and (iii) yield of white sugar (WSY). Both yield characteristics, regardless on soil, were affected to a greater extent by in-soil than foliar MgS application. The highest increments of TY and WSY were obtained in 2016, a year with fewer favourable weather conditions and in soil with a wider Ca:Mg ratio. The greatest effect of Kieserite on TY and WSY was observed under low rates of applied N (up to 80 kg/ha). It can be concluded that the right nutrition of sugar beet with MgS in the early stages of sugar beet growth is the prerequisite of an effective N management on soils rich in mineral N.

The waxy wheat shows special starch quality due to low amylose content. However, less information is available concerning the physicochemical properties of starch in different waxy wheat under different irrigation. In this study, two wheat near-isogenic lines (NILs) and a normal wheat cultivar were used to investigate the contents, size distribution and crystallinity of starch by biochemical methods, laser-diffraction and X-ray diffraction analysis. The amylose content in wheat grains was the lowest in waxy wheat lines, SJZ8-N, followed by the partly waxy wheat lines, SJZ8-P, and the highest in the normal wheat, SJZ8, with significant differences among wheat lines. Waxy wheat starch had more B-type granules and a higher degree of crystallinity than normal wheat starch, with the order as SJZ8-N > SJZ8-P > SJZ8. When compared with the conventional and water-saving irrigation, the rainfed treatment showed the lowest starch content, amylose content (except SJZ8-N), amylopectin content and relative crystallinity in the three wheat lines indicating that water deficiency was not benefited starch accumulation and crystal formation in wheat grains. It was concluded that (1) wheat lines not only differed in amylose content but also in size distribution and crystallinity of starch; (2) irrigation markedly influenced the physicochemical characteristics of wheat starch; therefore, the irrigation schemes could be adjusted to achieve high-quality wheat production.

Drought stress is one of the major limiting factors to crop productivity around the globe. It has been well documented that spermidine (Spd) plays an important key role in plant growth and development, especially in the defense response to stress. The objective of this study was to explore the effect of Spd on protecting photosynthetic apparatus in tall fescue under drought stress. Spd application significantly improved the OJIP (fluorescence rise kinetics O-J-I-P) curve compared to non-Spd application during drought. Exogenous Spd exhibited higher F_J (fluorescence value at the J-step (2 ms) of OJIP) and F_P (maximal recorded fluorescence intensity, at the peak P of OJIP) than non-Spd application. Moreover, normalised total complementary area (S_m) and the number of Q_A (primary quinone acceptor of PS II) reduction events (N) significantly reduced after the application of Spd in tall fescue under drought stress. In terms of quantum yields and efficiencies and specific energy fluxes, exogenous Spd notably decreased the values of efficiency of electron transfer from Q_B (secondary quinone acceptor of PS II) to PSI acceptors (δR₀), absorption flux per RC (ABS/RC) and trapping flux per RC (TR₀/RC) compared to the non-Spd application without watering. All the above suggested that exogenous Spd facilitated the photosynthetic system of tall fescue in drought. These observations involved in the electron transport capacity of photosystem II assist in understanding better the protective role of exogenous Spd in tall fescue under drought stress.

We evaluated the effects of mowing dominant grasses on root exudation and soil nitrogen (N) cycling by assessing metabolomics analysis of root exudates, microbial metabolism, the abundance of N-cycling-related prokaryotes, and different forms of N concentrations in soil. The treatments included Polygonum aviculare L. mowing (T1), Digitaria sanguinalis (L.) Scop. mowing (T2), and no mowing as the controls (CK1 and CK2). The results showed that compared with the no mowing control (CK1 and CK2), T1 and T2 root exudates contained 223 (178 up-regulated, 45 down-regulated) and 183 (40 up-regulated, 143 down-regulated) differential metabolites, respectively. The average well colour development (AWCD) could reflect the microbial metabolic activity. The AWCD values of T1 were increased while that of T2 decreased on the 2^nd day after mowing. The variation in root exudates was the main reason for the change in soil AWCD values and carbon utilisation of T1 and T2 on the 2^nd day after mowing. Mowing increased soil microbial biomass N content significantly in the T1 and T2 topsoil. The NO₃^--N and NH₄⁺-N contents in the 0-10 cm soil increased on the 2^nd day after T1 mowing with an increase in the nitrogenase iron protein gene (nifH), glutamate dehydrogenase gene (gdh), ammonia monooxygenase gene (amoA) of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) abundance. However, NO₃^--N content decreased on the 2^nd day after T2 mowing following a decrease in AOA-amoA and AOB-amoA gene abundance. The results of this study will facilitate the optimisation of sod culture orchard N management, reduction of N fertiliser input, and improvement of N utilisation efficiency.

The oil content and fatty acid composition were determined in the seed of 19 poppy genotypes (both landraces and modern cultivars) grown in three-year field trials. The total oil content ranged from 34.56-44.76%. The oil content in white-seeded genotypes (40.73-44.76%) exceeded the oil content in blue-seeded genotypes (34.56-40.34%) and ocher-seeded genotypes (38.36-42.69%). Linoleic acid (71.41-74.02%), oleic acid (12.35-15.51%) and palmitic acid (8.95-10.29%) were the most abundant fatty acids in the evaluated seeds of poppy genotypes. A significant negative correlation (-0.7574**) was found between linoleic and oleic fatty acids. The sum of polyunsaturated (PUFA), monounsaturated (MUFA) and saturated (SFA) fatty acids ranged from 72.43-74.91%, 12.90-16.14% and 10.99-12.46% of the total fatty acids, respectively. Both the total oil content and the content of individual fatty acids were mainly affected by the crop year (weather conditions); however, the effect of genotype and year × genotype interaction was also significant. Due to the favourable composition of fatty acids, the evaluated poppy genotypes can be a good source of nutritionally valuable oil.

The abundances of two pests, pollen beetle (Brassicogethes aeneus (Fabricius, 1775)) and cabbage seed weevil (Ceutorhynchus obstrictus (Marsham, 1802)), were measured before flowering and in the full bloom of oilseed rape cultivars with different phenologies (two yellow-flowering: DK Exssence (the earliest), DK Sensei (the latest) and one white-flowering in time between yellow-flowering cultivars), and the differences in their abundance in the selected cultivars were determined in plot experiments during 2015-2018. No significant differences in pollen beetle and cabbage seed weevil occurrence were observed between the cultivars in the pre-flowering period, but during flowering, the two yellow-flowering cultivars were more attractive than the white-flowering cultivar for both pests. In the white-flowering cultivar, 57% and 69% reductions in the pollen beetle and cabbage seed weevil populations, respectively, were found relative to the two with yellow flowers. Thus, the use of white-flowering cultivar (less attractive, later flowering) as the main crop and the yellow-flowering cultivar (more attractive, earlier flowering) at field edges, with the width of the one-track line, could serve as a strategy to manage oilseed rape pests during flowering. This control strategy which combines more and less attractive oilseed rape cultivars may contribute to a reduction in the use of pesticides and their negative impact on the environment.

Drought stress is a significant abiotic stressor that has a negative impact on crop production and global food security systems. Drought stress was applied to eggplant seedlings with various field capacities (FC), 80% FC as control, 50% FC, 35% FC, and 20% FC. AgNPs were synthesised from green chemical methods, whereas different concentrations of AgNPs (0, 0.1, 0.2, 0.5 µmol) were applied exogenously on drought-stressed eggplants. Drought stress decreased the growth parameters (plant height, fresh mass, dry mass, leaf area), photosynthetic pigments (Chl a, Chl b, carotenoids), and protein content while increased the proline, hydrogen peroxide (H₂O₂), malondialdehyde (MDA) content, and activity of the antioxidant enzymes, i.e., superoxide dismutase (SOD) and catalase (CAT). AgNPs restricted proline accumulation and reduced H₂O_2, MDA content by upregulating the antioxidant enzymes. Overall, the current study's findings indicated that AgNPs are an effective eco-friendly and low-cost application for plant growth under drought stress, with the potential to mitigate the impact of drought on plants.

To test whether praseodymium (Pr) regulates cadmium (Cd) tolerance, we explored the effects of Pr on enzymatic activities in the regeneration and biosynthetic pathways of ascorbate and glutathione in maize seedlings under Cd stress. The findings demonstrated that Cd stress increased enzymatic activities in the regeneration pathway (ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR)) and in the biosynthetic pathway of ascorbate and glutathione (γ-ECS and GalLDH), as well as ascorbate (AsA) and glutathione (GSH) contents. However, Cd stress significantly decreased AsA/dehydroascorbic acid (DHA) ratio and GSH/oxidised glutathione (GSSG) ratio, net photosynthetic rate (P_n), chlorophylls (Chl) and carotenoids (Car) contents, maximum photochemical efficiency of PSII (F_v/F_m), photochemical quenching (qP) and quantum efficiency of PSII photochemistry (Φ_PSII), as well as plant height and biomass. Application of Pr to Cd-stressed seedlings enhanced above enzymatic activities, AsA and GSH contents, AsA/DHA and GSH/GSSG ratios, P_n, Chl and Car contents, F_v/F_m, qP and Φ_PSII, as well as plant height and biomass. Meanwhile, the application of Pr to Cd-stressed seedlings reduced malondialdehyde (MDA) content and electrolyte leakage. The above results indicated

The goals of this study were to explore the characteristics of nitrogen (N) absorption and utilisation of chilli peppers (Capsicum annuum L.), improve the utilisation rate of nitrogen, and provide a theoretical basis for scientific fertilisation. In this experiment, pepper cv. Huoyanjiaowang was used as the material, and potted sand cultures and field randomised block experiments were conducted to study the effects of fertilisation of different forms of nitrogen on the photosynthetic characteristics, chlorophyll, nitrate nitrogen, alkaline nitrogen, capsaicin, dihydrocapsaicin and yield. In the pot experiment, the nitrogen application rates were 0, 10, 100, 320 and 600 mg/L, a level of nitrogen of 100 mg/L significantly inhibited the growth of pepper. With the increase in the application of nitrogen, the photosynthetic capacity gradually decreased, and 10 mg/L was the optimal nitrogen level. Under 0 and 10 mg N/L nitrogen levels in the field experiment, the content of chlorophyll of this group was significantly lower than those of other treatment groups, indicating that the plot lacked nitrogen. With the increase in the level of application of nitrogen, the contents of nitrate nitrogen and alkaline hydrolysis nitrogen in the soil increased. The yield of 153.18 kg/ha and 230 kg/ha nitrogen treatments was relatively high. Therefore, among the five nitrogen treatment levels, treatment with 153.18-230 kg N/ha was the most effective at stimulating the growth and yield of pepper.

Due to its nutritional, health-promoting and taste-related values, new cultivars are introduced every year. The aim of the study was to assess the biological value of Polish and Bulgarian cultivars of pepper grown in moderate climate conditions and collected at different degrees of maturity. Ascorbic acid, carotenoids, polyphenols, chlorophyll a, chlorophyll b, total chlorophyll and antioxidant activity (DPPH) were determined in air-dried fruit. The investigation included five Polish cultivars: Roberta, Marta Polka, Etiuda, Trapez, and Cyklon and five Bulgarian cultivars: Bulgarski Ratung, Sivriya, Kurtovska Kapiya, Delikates, and Dzuliunska Shipka. Its design involved randomised sub-blocks, with three replications comprising nine plants each. The area of a single plot was 1.44 m² (1.2 m × 1.2 m). The study confirmed the strong antioxidant properties of pepper grown in the field, without cover, and under temperate climate conditions. The vegetable is rich in vitamin C, polyphenols, carotenoids, chlorophyll pigments, and shows high antioxidant activity. However, the biological value of pepper is cultivar-dependent and is also determined by the fruit colouration degree. The coloured fruits are richer in vitamin C and carotenoids than the green ones, and when matured, they have greater antioxidant capacity. Green fruits contain more chlorophyll a, chlorophyll b and total chlorophyll than the coloured ones. The fruits of cv. Etiuda were the richest in vitamin C, of cv. Sivriya in polyphenols, of cv. Dzuliunska Shipka in carotenoids, and of cv. Trapez in total chlorophyll. Cv. Sivriya showed the strongest antioxidant properties.

Farmland soil samples from the northern and southern banks of the Wangbeng section of the Huaihe River Basin, China, were collected and treated with three different low-molecular-weight organic acids (LMWOAs) (malic acid, citric acid, oxalic acid). This study aimed to determine how these acids affect soil phosphorus activation. The results showed that the average activation rate of total phosphorus, inorganic phosphorus, Fe/Al-P and Ca-P in soil samples from the southern bank treated with malic and citric acid was above 162%, except for organic phosphorus, with the highest at 192.04%. The three organic acids displayed significantly greater phosphorus activation in the northern bank soil samples than those of the southern bank. However, the overall average activation rate in the northern bank soils was lower than that of the southern bank. The four factors of phosphorus species, acid species, acid concentration, and treatment time had significant effects on phosphorus activation in the soils from both banks. This study showed that the three organic acids significantly activated inert phosphorus in the soil. Among them, malic acid and citric acid had a stronger effect on activating soil phosphorus and increased the available soil phosphorus utilisation rate.

The content of macro- and microelements in dry samples of mushrooms of the species Macrolepiota procera, Boletus edulis and Cantharellus cibarius, collected at different areas in Bosnia and Herzegovina, was determined using the ICP-OES method (inductively coupled plasma optical emission spectrometry). Of the macroelements, K is the most represented, followed by S, P, Mg, and the least represented Ca and Na. Zn is the most represented of the essential microelements, followed by Fe, Se, Cu, Mn and Co. Al is the most abundant of the other trace elements followed by Ni and Cr. Of the toxic metals, the most represented is Cd, followed by Pb and As. There are differences in the concentration of micro- and macroelements in the mushrooms analysed, depending on the area from which they were collected because natural geology and geochemistry influence the content of macro- and microelements in wild edible mushrooms. The results show that the analysed mushrooms can be considered a good source of essential elements. The study also assessed potential health risks of heavy metals and the target hazard quotient (THQ) for As, Cd, Pb, Cu, Zn, Ni and Cr in the analysed mushrooms was lower than the safe level. The carcinogenic risk index revealed that Cd and Ni are the most prevalent pollutants in the mushrooms studied.