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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.

In this experiment, we investigated the effects of drought combined with exogenous silicon (Si) and potassium application on super sweet corn growth and development. Drought stress caused decreases in the stem diameter, leaf area, cob length, cob diameter, 100 seed weight, seed number, cob yield, biologic yield, and relative water content (RWC), but proline content and catalase activity were higher under drought stress conditions. The results of a two-year experiment showed that potassium sulfate application and foliar application significantly increased RWC in drought stress conditions, and the highest increase was related to treatment with potassium sulfate in an amount of 25 kg/ha. Under normal irrigation conditions, with 25 kg of potassium sulfate per ha and Si foliar application, the maximum cob diameter (5.85 cm) was observed. Si application did not significantly affect proline content under normal irrigation conditions but increased proline content under drought stress. The highest proline content (10.77 mmol/g fresh weight) was recorded in the Si application using 25 kg of potassium sulfate per ha under drought stress conditions. Also, applying potassium sulfate with silicone foliar spraying had no significant effect on biologic yield under normal irrigation conditions. However, under drought stress treatments, biologic yield increased by applying 15 and 25 kg/ha of potassium sulfate and Si foliar spraying. In summary, applying potassium sulfate and exogenous Si can enhance the antioxidant system of the plant, promote the RWC, thus improving biologic and cob yield, and enhance the drought resistance of super sweet corn.

If appropriately applied, tillage can positively affect the crop’s yield by enhancing the soil’s physical properties. Fertilisation also has beneficial effects on yield if applied at efficient rates by increasing available-to-uptake nutrients and improving soil’s chemical properties. A field experiment was carried out in Debrecen, Hungary, to evaluate the individual and the interaction effects of these 2 factors on sunflower and sweet corn. The cultivation methods applied were ploughing (C1), direct drilling (C2) and deep loosening (C3). In addition, 3 fertilisation rates were applied to each cultivation system: F1 (control, no fertilisation); F2 (100 : 50 : 70) kg NPK/ha and F3 (150 : 100 : 120) kg NPK/ha in a randomised complete block design (RCBD) with 4 replicates. Our results showed that fertilisation did not affect the yield of sweet corn measurably. However, C1 resulted in the highest yield, whereas C2 and C3 resulted in relatively similar yields. In sunflowers, the yields of both C1 and C2 were higher than that of C3. No significant differences were recorded between C1 and C2. The yields of both F2 and F3 were higher than the yield of F1. The differences between F2 and F3 were insignificant. It could be concluded that the cultivation method is a determining factor in the yield of sweet corn. The effects of both fertilisation and cultivation treatments were more detectable in sunflowers. The differences between the two fertilisation rates (F2 and F3) were insignificant in both species, indicating that the extra fertilisation levels might be unnecessary.

Plant-based indicators of water status, such as midday stem water potential (Ψ_stem) and leaf stomatal conductance (g_s), are used to optimise irrigation scheduling in horticultural crops because they integrate the effect of soil and climatic conditions and the internal physiological constraints. The use of these indicators relies on experimentally acquired thresholds that relate the value of the indicator to negative effects on yield. In five irrigation treatments, we monitored yield, fruit size and the courses of Ψ_stem and g_s throughout four consecutive growing seasons. We found that Ψ_stem was more sensitive to irrigation treatment than g_s. Both indicators increased with available soil water content (ASWC) and decreased with evaporative demands of the atmosphere (ET_C). On a seasonal basis, crop load had a stronger impact on g_s than Ψ_stem. In summary, our study explored the effect of environmental conditions and crop load on plant-based indicators of tree water status and can be useful for establishing thresholds for irrigation scheduling in apple tree orchards.

However, its underlying mechanism remains largely undetermined. In this work, we examined the impacts of the continuous application of pig manure fertiliser for 10 years on wheat yield in the calcaric fluvisol soil with a texture of sandy loam, and the relationship between soil microbial community composition and soil properties was also analysed. The wheat yield, yield components and wheat biomass were analysed by collected aboveground part. Soil nutrient, enzymatic activity and microorganism compositions were analysed by collected soil samples at the filling stage. The results showed that long-term application of pig manure fertiliser could remarkably increase wheat yield by improving soil nutrient availability, enzyme activities, and microbial composition. Moreover, soil pH, nitrogen content, dehydrogenase and urease were closely related to the soil microbial diversity. In conclusions, the long-term application of pig manure in combination with term mineral fertiliser could optimise microbial community composition by regulating the interaction between microbial species and enhancing soil enzyme activity and soil fertility, leading to increased wheat yield.

Soil macroarthropods, as a component of the soil community, directly feel the impact of land use changes. Not only the density but understanding the soil macroarthropods distribution pattern will help in providing an insight into the quality of soil health. The sampling process was carried out using the pitfall trap methods on the forest, logged forest areas, mixed gardens, and monoculture gardens in the tropical rainforest of Bukit Pinang-Pinang Padang, Indonesia. The results showed that the forest as a natural habitat supported the density of soil macroarthropods among other land use types. The density in the forest, logged forest area, mixed garden, and monoculture garden sequentially is about 20.29, 13.18, 15.2 and 12.21 indv/m2. The presence frequency high value of soil macroarthropods was found in the forest, and for some soil macroarthropods, such as Hymenoptera, Diptera, and Araneits, the importance value increases when their habitat is disturbed. The fertile soil in intensive monoculture gardens does not support the individuals’ total number, types, and density of soil macroarthropods. On the other side, the dominant soil macroarthropods prefer disturbed soil conditions and will decrease their presence frequency if chemical compounds are introduced into the soil. Land use change in the Bukit Pinang-Pinang tropical rainforest area causes changes in the distribution pattern of soil macroarthropods. The changing tendency of distribution patterns in fragmented habitats is due to nutrient availability, limited resources and land treatment. Habitat fragmentation affects not only the abundance and density of individuals and types of soil macroarthropods but also the distribution pattern, which not only threatens their existence and the environment but also has the potential to regenerate.

A study was conducted at the University of Venda Experimental Farm, Limpopo province, South Africa to determine the effects of tillage and mulching on selected soil properties, and yield of sunflower (Helianthus annuus L.). The experiment was laid out in a split plot design with three replications during the 2018/19 and 2019/20 cropping seasons. Treatments consisted of conventional tillage (CT) and minimum tillage (MT) and three levels of avocado leaf mulch (0, 6 and 12 t/ha). Bulk density (BD), aggregate stability (AS), infiltration rate (IR), soil water content (SWC) and grain yield were determined. Tillage had no significant effect on BD in either season but influenced SWC and sunflower grain yield. CT recorded a significantly higher AS than MT during 2018/19 cropping season. Tillage × mulch interaction was significant during 2018/19 season with CT at 12 t/ha mulch recording higher AS than the MT. IR was significantly influenced by tillage × mulch interaction in both seasons with MT recording higher IR than the CT during 2018/19. Avocado mulch had no significant effect on sunflower grain yield in either season but influenced SWC in 2019/20 season. It was concluded that avocado mulch could be a relevant component of conservation agriculture but long-term studies are needed to validate the benefits observed in this study.

Crop residue management and water saving are the two major issues for the sustainability of the rice-wheat cropping system. Therefore, a two-year field experiment was conducted in a split-plot design to study the combined effect of three rice residues (residue incorporation (RI), residue standing (RS) and residue removal (RR) and two wheat residue incorporation (WI) and residue removal (WR) management in main plots and two irrigation regimes, i.e., flood (F) and surface drip (SD) in subplots on the growth and water productivity of direct seeded rice (DSR). During both years, RI-WI resulted in significantly higher plant height (PH), leaf area index (LAI) and dry matter accumulation (DMA) than in other residue management treatments. Drip irrigation significantly increased PH, LAI, DMA grain yield, straw, and biological yield, along with a 9.6% irrigation water savings over flood irrigation. During both years, grain yield, straw and biological yield of DSR were significantly higher in RI-WI than in RR-WR and RR-WI. RI-WI had significantly greater apparent water productivity (AWP) and actual water productivity (RWP) of DSR. Drip irrigation had significantly higher AWP and RWP during both years than flood irrigation except RWP during 2017. Transpiration efficiency (TE) in rice residue incorporation was significantly higher than in rice residue standing and removal. During both years, the TE of drip irrigation was also significantly higher than flood irrigation. So, incorporating rice and wheat residues along with drip irrigation improves crop growth and water productivity.

The information on the behaviour of potassium (K+) in tropical paddy rice soils, which is important for a better understanding of the plant availability of K+ is still very limited. We compared the quantity-intensity (Q/I) relationships for K+ under conventional tillage and no-tillage systems in tropical paddy fields in the absence and presence of K+ fertiliser in the addition of nitrogen. The results showed that the values of the activity ratio for K (ARK) and potential buffering capacities (PBCK) in the no-tillage rice field were respectively 16% and 33% higher than that in the conventional tillage field. With the addition of K fertiliser, the value of exchangeable K in equilibrium (ΔK0) in the no-tillage paddy field was 67.9% greater than that in the conventional tillage field. This indicates that K fertilisation is more efficient when applied on a no-tillage paddy field. When the K fertiliser was added (49.8 kg K/ha), the application of N fertiliser at the rate of 115 and 184 kg N/ha resulted in a higher ARK value than that at the rate of 46 kg N/ha. This suggests that the simultaneous application of K and N fertiliser was able to increase exchangeable K in the soil. The application of no-tillage increased of the dry grain yield of rice (about 10%) compared with the application of conventional tillage. Meanwhile, there were significant relationships between the rice yield with the ARK and ΔK0. Moreover, the ARK was significantly correlated with K-uptake.

The aim of this study was to determine the heavy metals concentrations in soil, inflorescences of Brassica napus and rapeseed honey sampled from some regions of north-eastern Bulgaria. Thirteen locations were selected for experimental studies. The soils, plants and honeys samples were taken from conventional beekeeping areas away from major industrial pollutants. The median amounts of elements in the soil samples (mg/kg DW) are 1.1246 for Fe(s), 0.7048 for Al(s), 0.5636 for Pb(s), 0.1658 for Cu(s) and 0.0148 for Zn(s). The median amounts of heavy metals measured in the inflorescences of Brassica napus (mg/ kg DW) are 5.5430 for Fe(p), 2.9095 for Zn(p), 1.3225 for Pb(p), 0.2593 for Cu(p) and 0.2105 for Al(p). The median heavy metals concentrations in  tested honey (mg/kg DW) are 1.0026 for Fe(h), 0.1849 for Al(h), 0.1832 for Pb(h), 0.1250 for Zn(h), 0.0702 for. Cu(h). The relationship between the heavy metal in soil, plants and honey was investigated using the Spearman’s rank correlation coefficient. Significant differences in the concentrations of Fe(s), Al(s) and Pb(s) in soils, Fe(p) and Zn(p) in the plant samples, Fe(h) in honey samples from the different locations were found. The heavy metal content tested in honey did not pose a risk to human health.

The soil seed bank, as a potential source of ground vegetation renewal, plays an important role in the natural recovery and succession of vegetation as well as in the construction of ecosystems. To clarify the characteristics of the soil seed bank of Achnatherum inebrians and its relationship with the aboveground vegetation, the soil seed bank density, species composition and aboveground vegetation of three different grassland types, namely, desert, steppe and meadow, were investigated by means of field survey sampling and indoor germination experiments. The results showed that the seed bank densities of the three habitats were ranked as desert (1 422.22 seeds/m²), steppe (2 077.78 seeds/m²) and meadow (3 722.22 seeds/m²). The numbers of species were 16, 11 and 17, respectively. With respect to the vertical allocation, the soil seed banks in each habitat were shallow, and the seeds were mainly concentrated in the soil surface layer (0–5 cm). The species richness of the soil seed banks in the three habitats was higher than that of the aboveground vegetation, but there were some differences in richness, evenness and dominance. The species richness and diversity of soil seed banks and aboveground vegetation in meadow habitats were higher than those in desert and steppe habitats, indicating that the soil seed banks and aboveground vegetation in meadow habitats had higher stability. There was a significant positive correlation between the density of temporary soil seed banks and the density of aboveground plant communities in grassland habitats. The results may provide some reference for the prevention and control of Achnatherum inebrians in the three habitats.

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.

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.