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The effects of long-term various organic fertilisers application on ecosystem respiration components and net carbon budget have rarely been investigated in a hillslope agricultural ecosystem. Hence, we measured the rates of plant autotrophic (R_a) and soil heterotrophic respiration (R_h) from 2011 to 2012 with five treatments: no fertiliser (CK); mineral fertiliser (MF); MF combined with swine manure (MFS); MF combined with crop straw (MFC), and swine manure (SM). Our results confirm that R_a was found to be more temperature-moisture sensitive than R_h, whereas R_h was more temperature sensitive than R_a. Soil microbial biomass carbon (MBC) is a major factor influencing the temperature sensitivity coefficient of Rh (Q₁₀), thereby application of organic fertilisers combined with mineral fertilisers (MFS and MFC) significantly increased annual by 19.3% and 17.2% compared with MF treatment. Annual carbon emissions via R_h and R_a under MFS, MFC and SM treatments were increased by 24.6, 28.5, 48.8% and 6.6, 10.6, 1.8%, respectively compared with MF treatment (4.6 and 23.2 t C/ha/year). Net primary production (NPP) under MFS, MFC and SM treatments were increased by 5.4, 6.01, and 15.6% relative to MF treatment (13.6 t C/ha/year), respectively, and the corresponding net ecosystem carbon budget (NECB) increased by 121.2, 172.8, and 342.4%. Our findings establish that long-term organic fertilisers application increase plant autotrophic, heterotrophic respiration and net ecosystem carbon budget, which can increase the carbon sink function. Overall, crop straw combined with mineral fertiliser is a feasible agronomy practice to increase carbon sink function, reduce soil erosion and maintain crop yield.

Panax ginseng Meyer is one of Asia’s most popular medicinal plants, with triterpene saponins as principal bioactive compounds. The present study investigates the possibility of ginseng cultivation in Lahaul & Spiti, Himachal Pradesh, India in the Western Himalayas focusing on growth characteristics, and ginsenoside content in the roots. Plant growth parameters increased with an increase in the crop age and reached maximum maturity at the age of five years along with the production of a good amount of seeds and roots. Root fresh and dry weight of the five-year-old plant was 142.6 g and 45.5 g, respectively, which almost doubled as compared with the four-year-old plant. The HPLC analysis of P. ginseng roots leads to the identification of 14 compounds representing 31.81 ± 2.89 mg/g of total ginsenoside contents, where Rb1, Rg2 and Re were found to be major ginsenosides with 7.53 ± 0.37, 7.04 ± 0.61 and 3.77 ± 0.26 mg/g content. Protopanaxadiol (PPD) and protopanaxatriol (PPT) represent the major classes of ginsenosides present in the ginseng roots with a 0.98 ratio of PPD/PPT. Our studies revealed that the soil and climate of the Lahaul and Spiti district of Himachal Pradesh State in the Western Himalayas are suitable for the cultivation of P. ginseng with good content of ginsenosides in five-year-old roots.

Earthworms dominate the soil biota, and different structural and functional features of their biology and ecology have been studied and exploited to evaluate their contributions as ecosystem services. Due to their feeding ecology, burrowing and casting activity, earthworms are involved in the nutrient cycles, and therefore it is opportune to be considered when the biogeochemical cycles of the terrestrial ecosystems are analysed. All structural, microbiological and biogeochemical impacts of earthworms in soil start with their feeding and digestive functions, which end in casting. The casting activity consisting of the excretion of the ingested soil and organic matter after digestion processes depends on earthworm feeding behaviours and ecology, even described in the current literature as a new ecological feature: the casting ecology. The complexity of the chemical relationships occurring inside earthworm casts between main nutrients (organic carbon, nitrogen, phosphorus, potassium, calcium) highlights the complexity of the biogeochemical cycles and the great earthworms’ contribution to these cycles in the ecosystems towards a better understanding of the soil sustainability through the soil biodiversity contribution. Due to this great contribution, the earthworms’ casts should be included as indicators in the integrative conservation management of the ecosystems, as a re-thinking of the concept of ecosystem sustainability.

This study aimed to determine the effect of tea planting age on stoichiometric ratios of microbial biomass carbon (MBC), nitrogen (MBN), and phosphorus (MBP) and soil microbial quotient (SMQ, expressed as qMBC, qMBN, and qMBP, respectively). A chronological sequence of tea plantations (3, 8, 17, 25, and 34 years) was selected in a small watershed in the Three Gorges Reservoir Area, and a slope farmland was selected as control. The results showed that with the increase of tea plantation age, soil and microbial biomass C, N, P contents, soil C : N and C : P elevated significantly, while soil N : P overall declined; the MBC : P and MBN : P increased first and then decreased, but MBC : N varied insignificantly. The tea plantation age affected SMQ notably. qMBC first decreased and then increased following the tea planting age, while qMBN and qMBP went up in a fluctuating pattern. In this study, qMBC positively correlated with soil N : P and microbial biomass C : N : P, but negatively correlated with soil C : N and C : P; on the contrary, qMBN and qMBP negatively correlated with soil N : P and microbial biomass C : N : P, but positively correlated with soil C : N and C : P. Generally, the variations of soil microbial biomass and SMQ could reflect the soil quality of tea plantations.

Development of methods for bioremediation of soils contaminated with petroleum products is one of the most urgent tasks of our time. This task is more difficult to perform in high-mountainous landscapes, at an altitude of more than 4 000 m a.s.l. Moreover, these high-mountain ecosystems are the most vulnerable to various kinds of anthropogenic impacts, and therefore the relevance of bioremediation is obvious. The research was conducted in the high-altitude ecosystems of the Kyrgyz Republic at the Kumtor mine. In this study was carried out on the bioremediation of oil contaminated soil using biostimulation, bioaugmentation and biostimulation + bioaugmentation remediation techniques for 90 days in the climatic conditions of high mountain region. The biostimulation treatment showed the highest total petroleum hydrocarbons (TPH) biodegradation percentage 62.78% compared to the bioaugmentation 50.63% and biostimulation + bioaugmentation 49.11%. Thus, the method of biostimulation proved to be the most effective method for bioremediation of soils contaminated with petroleum products. The application of this method could be one of the successful methods of recycling contaminated soils. This study demonstrated the possibility of restoring TPH-polluted soils using biological methods of soil treatment in climatic cold conditions of high mountains.

Nitrogen dynamics in soil produce N2O emissions. To decrease N2O emissions and conserve N, recent studies have focused on chemicals derived from root exudates that inhibit nitrification. However, selective plant breeding could be used to control nitrification activity in soil instead of fertilisers or synthetic nitrification inhibitors. In this study, we investigated the relationship between nitrification rates (NR) and related N dynamics and plant characteristics for 11 maize varieties with varying levels of nitrification inhibition (NI) compared to Brachicaria humidicola (Bh) as the positive control. In a greenhouse experiment, soil concentrations of NI, NR, NH4+-N, and NO3--N and nitrogen uptake by plants were measured. Six maize varieties had a 1.1–1.6 times lower NR than Bh. Low-NR varieties had higher NI and lower root-to-shoot ratios. NI was positively correlated with total N and shoot N content but not with cumulative N2O and NH4+-NO3-. These results show that maize has the capacity to reduce soil nitrification while increasing the total N in the soil and shoot N content in maize.

Advocating proper phosphorus (P) fertilisation is necessary to save this limited natural resource and to save the investment in rice cultivation. This study aimed to evaluate changes in phosphorus availability, total phosphorus in soil, phosphorus buffering capacity, and phosphorus saturation in the long-term phosphorus fertilisation in the paddy rice system. Soil samples were collected in the harvest stage after seven consecutive crops over three years at Can Tho city, Vietnam. The applied phosphorus fertiliser rates were: no phosphorus fertilisation (P0), 17.4 kg P/ha (P17.4), and 26.2 kg P/ha as farmer’s practice (P26.2). The results showed that the soil phosphorus buffering capacity in P0, P17.4 and P26.2 treatments was 9.49, 9.08 and 9.04 mg/kg, respectively. The degree of phosphorus saturation of P17.4 and P26.2 treatments ranged from 17.7% to 25.5%, showing the medium to high risk of phosphorus leaching. This study indicated that the application of phosphorus rate higher than 17.4 kg P/ha might result in the reduced soil phosphorus buffering capacity in the intensive rice cropping system in the Vietnamese Mekong Delta region. Our results implied that the application of a rate lower than 17.4 kg P/ha/crop could be extended to the other rice-growing (double/triple rice) areas in the Vietnamese Mekong Delta region or other paddy rice on alluvial soils in Asia.

Due to ongoing climate change, the need for the application of adaptive strategies in agriculture is increasing, particularly in areas with insufficient rainfall, high temperatures and weather fluctuations during the vegetation period. Therefore, an experiment was conducted in 2020 and 2021 to determine the influence of superabsorbent polymers (SAPs) on morphological, physiological and production traits of maize. SAPs were applied using a method of seed coating, which is considered cost-effective and environmentally friendly. Due to the impact of SAPs, significantly larger weights of leaves and roots, as well as the length of roots in the initial growth stage, were found. Furthermore, the SAP treatment condition found significantly larger values of leaf relative water content and spectral indexes PRI (photochemical reflectance index) and NDVI (normalised difference vegetation index). Applying SAPs also led to a significant increase in spikes per plot and grain yield of maize. Moreover, the results significantly impact the interaction between year and treatment. The correlation analysis indicates a higher correlation between the observed traits in the SAPs treatment condition, which subsequently impacted the final maize production. These results confirm that applying SAPs can be considered a suitable strategy for mitigating the impacts of adverse weather conditions, especially in terms of sustainability and maintaining maize production.

The tillage depth plays a critical role in solving soil compaction - a global problem of soil degradation. However, to date, there are few research reported about tillage depth, and the standard of optimum tillage depth is lacking. Therefore, we conducted a meta-analysis to quantify the effect of tillage depths on crop yield across a global scale, and then to analysis their influence factors such as local climate, soil properties, and managements. Moreover, a global distribution of the optimal tillage depths was estimated by using a random-forest model. Overall, our result demonstrated that crop yield first increased within tillage depths from 25 to 35 cm, and then reduced under higher depth of deep tillage compared to conventional tillage, according to 1109 wheat, maize and soybean (WMS) yield observations from 202 studies and 109 publications. Visibly, 35 cm hence became the optimum tillage depth of WMS across the world, while it varies with different regions. Furthermore, higher crop yields observed in areas with a humid climate, high clay contents, and large bulk density under the optimal depth 40, 35 and 45 cm, respectively. In contrast, a lower yield was observed in areas with arid climates, silty and sandy soils, and lower bulk density within optimal depth of 25 cm, 30 cm, and 25 to 35 cm. Human management efforts, including fertilizer addition, irrigation, straw returning, and changing of cropping system or crop species mostly increased the crop yield under deep tillage. Particularly, our meta-analysis indicated that straw returning needs a greater depth. Finally, we predicted the distributions of optimum depths, which showed that 30 and 35 cm were the optimum tillage depths in the temperate and tropical regions, and the total crop yields of global WMS increased by 2689 million tons per year under the optimal tillage depth, compared with the conventional tillage.

Surface runoff and soil losses in the case of potato cultivation using de-stoning technology on gentle slopes (Haplic Cambisol) were studied in 2020–2022. Different ridges shapes were compared: control (smooth shaped ridges), pits, pits plus loosening, pits plus loosening plus cover crop (Triticum aestivum L.) sowing in trail furrows. Runoff and soil losses were studied approximately 1 and 2 months after planting potatoes. The obtained results showed the highest reduction of surface runoff and soil losses in the treatment with cover crop sowing. In this variant, soil losses were reduced by 65–81% (1 month after planting) and 54–85% (2 months after planting) in case of simulated rainfall on the soil with natural moisture (or these losses were reduced by 51–93% and 50–76% in case of 15-min rainfall). On average, tuber yields reached 29.4 t/ha (pits + loosening) to 30.6 t/ha (pits) in 2020–2022. The different abilities of the tested shapes of ridges and furrows to retain water did not significantly affect the achieved yields of tubers, as rainfall was not a limiting factor in the monitored period. The yield differences among all tested treatments reached units of tons per hectare if the entire dose of nitrogen was applied at planting. Splitting the total nitrogen dose (50% at planting, 50% at loosening) gave significantly (P < 0.05) higher yields (34.2 t/ha) than a single application at planting. The treatment pits plus loosening with fertilisation provided a 19–26% higher tuber yield than pits plus loosening with a total N dose applied at planting.

Long-term field experiments provide a valuable dataset for predicting changes in soil organic carbon (SOC) stocks in different agricultural systems. The RothC-26.3 model was used to simulate changes in SOC in the monoculture of spring barley (Hordeum vulgare L.) and the Norfolk crop rotation during 1972–2100. The potential of the Gleyic Fluvisol Clayic to sequester organic carbon was investigated. The studied soil was heavily textured, with medium organic carbon content. Four management scenarios in the monoculture and six management scenarios in the Norfolk crop rotation were evaluated. Three different global climate models (MPI, MRI, CMSS) representing the uncertainty of future climate conditions were used. Results showed that carbon stocks were mainly influenced by plant residue inputs and exogenous organic materials application. The projection showed trends of carbon stocks decreasing in the case of monoculture management. Results also documented that management scenario D with straw incorporation and intercrops represented sustainability and carbon stock increase during all modelled climate scenarios. The SOC stock at the end of the century was approximately 66 t/ha. This represents a moderate sequestration of SOC of approximately 0.09 t/ha/year.

Glyphosate is a widely used agrochemical. Nevertheless, only a few studies have investigated its effect on bees, specifically its influence on their foraging activity. This article provides a summary of the prominent research results on this issue, published in journals in the field of experimental biology. The effect of commonly used concentrations of glyphosate on honey bee navigation has been evaluated in several studies, as well as concentrations that are reportedly sublethal. Exposure to this herbicide increases the flight time back to the hive and affects the flight trajectories of these bees. These results imply that glyphosate at certain concentrations reduces their sensitivity to nectar rewards in associative memories. The contact of bees with non-lethal concentrations of glyphosate results in sublethal effects that affect foraging. In the future, the behaviour of glyphosate and its effect on bees in their natural environment need to be explored.

Biochar is the carbon-rich product obtained when biomass is anaerobically heated. In this study, different materials (corn straw and peanut shell) and pyrolysis temperatures (350, 450 and 550 °C) affect the elemental composition, surface structure, and biochar properties. The results showed that the carbon (C) content in biochar increased as the temperature increased, but hydrogen (H) and nitrogen (N) did not change. The alkane overpressure of corn straw and peanut shell increased first and then decreased with the increased temperature; the fatty alkyl chain disappeared, but the ash content increased at 550 °C. At high temperatures, the aromaticity (H/C ratio) and hydrophobicity (O/C ratio) of biochar become "carbon-rich particles", while the polarity (O + N)/C decreases significantly. The pore wall of biochar became thinner with the increase in pyrolysis temperature, the internal pore structure became larger, and a large number of micropores appeared in biochar. Biochar pyrolysed at 550 °C has much higher C, ash content, pore, and stronger buffering capacity, and thus is more promising to improve soil health.

The influence of toxic elements, such as arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn), in the root zone of As-hyperaccumulator Pteris cretica 'Albo-lineata' and non-As-hyperaccumulator P. straminea, on the enzymatic activity of β-glucosidase, dissolved organic carbon (C) in soil, toxic element accumulation in fern roots, and root biomass were evaluated in a pot experiment. Ferns were cultivated in soils from the locality of Suchdol (control) and Litavka (high contamination) for six months. For all toxic elements, an increasing trend in their contents in the roots was observed with soil contamination for both ferns. Differences between ferns were observed in As and Zn accumulation. Pteris cretica had a significantly higher As accumulation than P. straminea. Zinc accumulation in the roots showed an opposite trend. A significant difference between ferns was confirmed in the dissolved organic C content. Our results showed a significantly higher content of dissolved organic C in the P. straminea root zone than in P. cretica. The significant effect of toxic elements in the soil on β-glucosidase activity was observed. Toxic elements inhibited β-glucosidase activity in the root zone of P. cretica, and an increase in P. straminea was determined in the Litavka soil. The results suggest a higher sensitivity of P. straminea to toxic element contamination in soil, leading to increased β-glucosidase activity and increased dissolved organic C content.

Soil aggregate stability (SAS) is an important factor for soil quality and fertility. There are limited possibilities to influence this soil property, but one investigated method is the application of additives which have the potential to improve SAS. We established a four-year field experiment on a clay-loam Luvisol with poor soil structure to monitor SAS following the application of additives and grassland revegetation. Treatments included: (1) the untreated control; (2) compost; (3) biochar; (4) liming; (5) cattle manure; (6) woodchips; (7) woodchips + fungi inoculation; (8) pellets; (9) pellets + fungi; (10) hydrogel and (11) the change of arable land to grassland. The lowest 23.39% average SAS value was recorded for the untreated control, and then 23.92% for lime treatment, and the highest 27.69% average value was for hydrogel treatment, followed by woodchips with 27.22% and woodchips + fungi with 27.02%. A significant SAS increase of more than 200% was evident on the grassland two years after the trial’s establishment, and this was also associated with other improved physical and chemical soil properties. Finally, while most of our applied soil additives were relatively ineffective in agricultural practice, grassland revegetation is highly recommended for its rapid increase in soil aggregate stability.

Hyperspectral imaging technology has emerged as a prominent research area for quantitatively estimating soil nutrient content owing to its non-destructive, rapid, and convenient features. Our work collected the data from soil samples using the hyperspectrometer. Then, the data were processed. The competitive adaptive reweighted sampling (CARS) algorithm reduced the original 148 bands to 13, which accounted for 8.8% of the total bands. These selected bands possess a certain level of interpretability. Based on the modelling results, it can be concluded that the prediction model constructed by the least squares support vector machine (LSSVM) exhibited the highest accuracy. The coefficient determination, root mean square error, and ratio performance deviation were 0.8295, 2.95, and 2.42, respectively. These findings can provide theoretical support for the application of hyperspectral technology in detecting the content of the AHN in soil. Moreover, they can also serve as a reference for the rapid detection of other soil components.

Laboratory-scale testing methods applicable to evaluation of contaminated subsurface microbial communities are discussed in relation to their potential in supporting effective site bioremediation. Both culture-dependent and culture-independent techniques are considered here with special emphasis on their capacity to contribute to bioremediation system design, in optimal cases by providing information on contaminant degradation rates. In this regard, microbial soil respiration tests seem to be the most useful tool since microbial soil respiration is a sensitive and easily measurable parameter for determination of metabolic activity within the sample and is closely related to other microbial parameters such as microbial biomass.

The objective of this study was to evaluate variations in potato tuber yield with the selected land and soil characteristics including (i) topography (elevation and slope); (ii) geometry (horizontal coplanar geometry (HCP)and perpendicular coplanar geometry (PRP)); (iii) hydrology (volumetric moisture content; θv), and (iv) chemistry (phosphate, potash, organic carbon; organic carbon and pH). Analyses of the data collected across four potato fields, two each in Prince Edward Island and New Brunswick (NB), showed that the tuber yield negatively correlated with the field slope and positively correlated with most of the soil characteristics studied. Field elevation affected yield only under certain conditions such as higher range of elevation (≥ 7 m) (Field 2 in NB). Among soil characteristics, only HCP and PRP correlated with field elevation. The slope and elevation explained 22% to 36% variability of yield. Investigations of yield and topography by zonal analysis showed that yield was lower in zones of higher slope or elevation and lower θv, as the mean θv decreased in zones with a higher slope.

Maintaining nitrogen (N) balance and inhibiting N leaching loss in the soil-crop system is crucial to maintaining yield and reducing the environmental pollution. This study investigated the effects of soil NO₃^--N content and accumulation, eggplant yield, N leaching and balance response to biochar addition, including regular fertilisation and irrigation (W + F), biochar addition with regular fertilisation and irrigation (W + F + B), and biochar addition with 20% fertilisation and irrigation reduction (0.8W + 0.8F + B) treatments. Compared with W + F, W + F + B and 0.8W + 0.8F + B increased soil NO₃^--N content in 0-40 cm and soil NO₃^--N accumulation in 0-20 cm, and raised harvest index, N surplus and balance. Simultaneously, 0.8W + 0.8F + B compared to W + F enhanced N use efficiency and N partial factor productivity, conversely, it decreased N dry matter production efficiency, N surplus and balance. Stepwise regression analysis demonstrated that the effect of NO₃^--N leaching lasted in 60 cm under biochar addition in the first year, and lasted in 20 cm without biochar application in the next year. Altogether, biochar addition with 20% fertilisation and irrigation reduction is the most suitable management strategy to decrease N surplus and leaching, and maintain eggplant N uptake in a two-year cycle system on greenhouse vegetables in Mollisols.

The aim of our three consecutive years (2017-2019) field trial was to obtain information as to the effect of weather conditions of the actual year as well as to assess the impact of some technological parameters such as fertilisation, the choice on the hybrid type on the yield parameters, phytosanitary conditions and mycotoxin contamination of maize. According to our results, the climatic characteristics of the years, the examined hybrid characters (FAO 310 and 490) and the fact of N-fertilisation had significant effects on yield parameters and grain moisture content. The additional N-supply did not affect the development or severity of stem rot in any of the hybrid effects. In this respect, the year effect appeared to be the decisive factor since much higher stem rot values were recorded in the plots of the longer growing season hybrids. Among the mycotoxins examined, only zearalenone and fumonisin found in the harvest were significantly influenced by the effect of the year, the length of the growing season as well as nutrient replenishment. It can be stated that the applied technological parameters have a major effect on the expression of this toxin load in maize. Dry maize stocks that have lost their water in the vegetation are predisposing factors for toxin accumulation. N-content of soil and that of plants can play a different role in mycotoxin accumulation in maize plants.

Peatlands, as important global nitrogen (N) pools, are potential sources of nitrous oxide (N₂O) emissions. We measured N₂O flux dynamics in Hani peatland in a growing season with simulating warming and N addition for 12 years in the Changbai Mountains, Northeastern China, by using static chamber-gas chromatography. We hypothesised that warming and N addition would accelerate N₂O emissions from the peatland. In a growing season, the peatland under natural conditions showed near-zero N₂O fluxes and warming increased N₂O emissions but N addition greatly increased N₂O absorption compared with control. There was no interaction between warming and N addition on N₂O fluxes. Pearson correlation analysis showed that water table depth was one of the main environmental factors affecting N₂O fluxes and a positive relationship between them was observed. Our study suggests that the N₂O source function in natural temperate peatlands maybe not be so significant as we expected before; warming can increase N₂O emissions, but a high dose of N input may turn temperate peatlands to be strong sinks of N₂O, and global change including warming and nitrogen deposition can alter N₂O fluxes via its indirect effect on hydrology and vegetation in peatlands.

Aeroponics would appear to have a number of potential attributes to make potato production more efficient. In a 3-year experiment, from 2019 to 2021, potatoes were grown in aeroponic units using two nutrient solutions as well as in a conventional polycarbonate greenhouse in a substrate. Potato cultivars Adéla, Zuza and Ornella were used in all experiment years. No statistically significant effect of nutrient solution or potato cultivar on the number and weight of tubers was found in the trial. However, the advantages of aeroponics over conventional technology were statistically proven. The number of tubers per plant in aeroponic units ranged from 2.4 (2019, cv. Adéla) to 41.0 (2021, cv. Zuza), while in the greenhouse, they ranged from 3.9 (2019, cv. Adéla) up to 12.6 (2021, cv. Adéla). The average weight of tubers in aeroponic units ranged between 2.0 g and 9.9 g per plant (2 to 10 successive harvests), and in the greenhouse, 22.7 g to 41.9 g per plant (single harvest). The influence of cultivar on the average weight of tubers within individual cultivation technology variants was statistically proven only for polycarbonate greenhouse: only one harvest after the end vegetation.

To study the difference among cytoplasm at the different nitrogen conditions, a research experiment was conducted using five different cytoplasmic male sterile (CMS) hybrid rice with nitrogen levels at N0, N1, N2, and N3; the nitrogen application rates were 0, 90, 180, and 270 kg/ha, from 2018 to 2019. Results showed that among tested cultivars of CMS hybrid rice, JW (J803A × Chenghui727) showed the highest yield in both years for the low nitrogen and high nitrogen treatments. The dry matter accumulation and translation of JW type in nutritive organs were higher than that of others during the low nitrogen level (N1). We concluded that the nutrient translocation within plants organs and dry biomass accumulation were highly dependent on CMS type and nitrogen application. This research indicates that selecting a rice cultivar with greater efficiency of nitrogen is favourable for raising the number of grains per panicle, grain yield, and nitrogen use efficiency. JW cytoplasm displayed great efficiency in low nitrogen, which is a potential cytoplasmic resource.

Exogenous carbon (C) not only regulates plant growth but also provides energy for microbes and improves the soil environment. We hypothesised that exogenous C could improve plant growth by affecting the soil environment. Therefore, pot experiments were conducted and peanut cvs. Huayu 22(H) and NN-1(B) were used under three different treatments (the control, single nitrogen (N), and N combined with glucose (CN)). The results showed that the abundance and diversity of N-fixing bacteria are obviously influenced by the C and N, and exogenous C can promote the restoration of microbial diversity. The relative abundances of Burkholderiales were increased under HCN and BCN to 9.8% and 9.5%, respectively, compared to the control (3.9%, 2.5%). The abundance of N fixation bacteria increased mainly due to the soil nutrient change. In comparison with the single N treatment, the addition of the C significantly decreased the soil NH4+-N and NO3--N contents by 31.0% and 13.3%, respectively. And the activities of soil urease and nitrogenase were significantly increased. Compared to the control, single N significantly limited the root development, while the addition of C played a promoting role in root growth. Plant N accumulation increased compared with the control, but there was no significant difference between N treatment and CN treatment. These results indicated that exogenous C promoted soil microorganism activity and strengthened plant growth by changing the soil environment.

To assess the response of two safflower genotypes to auxin foliar application under late-season drought stress using a factorial split-plot experiment with the randomised complete block design, a two-year experiment (2016-2017 and 2017-2018) was conducted in Iran. The watering regime as specified in two levels including, regular irrigation and drought stress in main plots and two safflower genotypes and auxin foliar application in two levels including non-foliar application (control) and auxin foliar application at a concentration of 30 ppm were categorised in subplots. Drought stress at the seed filling stage reduced the safflower seed and oil yield. Moreover, a significant drought-induced decrease in linoleic acid, palmitic acid and behenic acid content, as well as an increase in oleic acids, was observed in two safflower genotypes. Among two safflower genotypes, the early maturing genotype less affected by drought and Goldasht had higher seed yield than the Padideh by 814 kg/ha, respectively. Auxin foliar application alleviates the adverse effects of drought, which led to an 18% increase in seed yield and components. However, the auxin application had no effect on the safflower seed oil content but palmitic acid content was affected by auxin foliar application. Generally, safflower along with auxin application can be recommended to develop safflower cultivation in semi-arid areas.

The effect of soil selenate application to two different soils (Phaeozem and Cambisol) on biomass yield and selenium (Se) uptake by spring wheat (Triticum aestivum L.) was investigated in a pot experiment. Additionally, organic amendment (fugate, i.e. liquid by-product from the biogas plant) was applied to assess (i) the effect of organic matter on the bioavailability of Se and (ii) the fugate (containing 2.3 mg/kg of Se) as a potential source of Se for plants. Selenium was applied at two levels: 6.4 µg/kg (Se1) and 32 µg/kg (Se2) of soil. The efficiency of biofortification and the distribution of selenium within individual plant compartments were assessed in this case. The highest Se contents in the grain were achieved in the treatments receiving NPK fertiliser together with selenate, 455 µg/kg (Se1) and 2 721 µg/kg (Se2) when wheat was planted in Phaeozem. Fugate in co-application with selenate significantly reduced Se content in wheat plants as compared to treatments enriched solely with selenate. The lower Se contents in the wheat plants growing in Phaeozem were due to the biodilution effect, whereas in Cambisol, the decrease in wheat Se uptake was not clearly driven by a particular factor.

The honey bee is one of the insects that is significantly endangered by the application of pesticides in the cultivation of crops. Not only is acute toxicity dangerous, but the importance of chronic poisoning by low doses of pesticides in hives is growing. The behavior of bees can be affected not only by insecticide residues but also by herbicide and fungicide residues. In 2016-2018, samples of bee bread were analysed for pesticide content at 25 different localities from intensive agricultural production areas of the Czech Republic. Substances were extracted by QuEChERS and determined by liquid chromatography, together with mass spectrometric detection. We detected up to 18 pesticides in one sample. In total, during 2016-2018, we identified 53 active substances. Fifteen substances (31%) were herbicidal, 23 substances (47%) of fungicidal nature and 6 substances (12%) of insecticidal nature. The coefficient of variation showed large differences in the frequency of revealed pesticides between years. For substances sprayed outside period attractive for pollinators (mainly herbicides and some fungicides), the usual methodology cannot reliably determine the degree of contamination, and thus the actual contamination with these substances may be even higher than demonstrated in this study.

The production of summer maize is greatly affected by nitrogen (N) sources through regulating root growth and distribution. Four N treatments in the field experiment were designed as UAN (urea ammonium nitrate solution was applied under traditional side-dressing method), urea (urea was applied under traditional side-dressing method), UWFI (UAN was applied underwater and fertiliser integration technology) and CK (no N applied). The results showed that the root length density, surface area density and volume of DH605 (mid-late hybrid) and DH518 (mid-early hybrid) under UWFI were higher than other treatments, especially in shallow layers. The root absorption area of each soil layer under N application treatments varied with the growth stage. The grain yield and the accumulations of N, P and K in the shoots showed the trend of UWFI > UAN > urea > CK. Compared with UAN and urea, the nitrogen agronomic efficiency of UWFI treatment increased by 40.5~78.6%, and the nitrogen partial factor productivity increased by 4.75~7.61%. Consequently, rational application of UAN would improve root traits, nutrient uptake and utilisation, and yield of summer maize.

This study investigated the influence of soil undergoing different crop rotations on the CH₄, CO₂ emissions, and decomposition of rice straw. The studied soil undergoing crop rotation systems were rice-rice-rice (SR) and baby corn-rice-mungbean (SB). Two main microcosm set-ups: anaerobic (SR-AN, SB-AN) and aerobic (SR-AE, SB-AE) conditions. Litter bags containing rice stems were inserted into the soil and recollected at different time points for chemical analysing and the gas sampling was collected to measure the CO₂ and CH₄ emissions. The results indicated that the total carbon (TC) decreased around 30%, and the TC removal in anaerobic was significantly higher than in aerobic conditions. The residue cellulose content varied in a range from 68.2% to 78.6%, while the hemicellulose content varied from 57.4% to 69.3% at day 50 after incorporation. There were no significant differences in the total nitrogen removal, cellulose, hemicellulose, and lignin contents among the microcosm set-ups. CO₂ emission increased in all the microcosm set-ups with the treatments without rice straw (CTSR, CTSB) in both aerobic and anaerobic conditions. CH₄ release in the SR-AN treatments did not differ significantly compared with the SB-AN treatments. This study confirmed that the decomposition of rice straw residues is faster in the anaerobic paddy soil condition compared to the aerobic crop rotation condition.

This study evaluated the phytoremediation potential of eight native plant species on heavy metal polluted soils along the Spreča river valley (the northeast region of Bosnia and Herzegovina). Plants selected for screening were: ryegrass (Lolium perenne L.), common nettle (Urtica dioica L.), mugwort (Artemisia vulgaris L.), wild mint (Mentha arvensis L.), white clover (Trifolium repens L.), alfalfa (Medicago sativa L.), dwarf nettle (Urtica urens L.) and yarrow (Achillea millefolium L.). All aboveground parts of selected native plants and their associated soil samples were collected and analysed for total concentration of Ni, Cr, Cd, Pb, Zn and Cu. The bioaccumulation factor for each element was also calculated. The levels of Cr (90.9-171.1 mg/kg) and Ni (80.1-390.5 mg/kg) in the studied soil plots were generally higher than limits prescribed by European standards, indicating that the soils in the Spreča river valley are polluted by Cr and Ni. Among the eight screened plant species, no hyperaccumulators for toxic heavy metals Ni, Cr, Cd and Pb were identified. However, the concentrations of toxic heavy metals in the above-ground parts of Artemisia vulgaris L. and Trifolium repens L. were significantly higher than in the other studied plants, indicating that both plant species are useful for heavy metal removal.