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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.

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.

Tripleurospermum inodorum (L.) Sch. Bip. is one of the most economically important and yield-reducing weeds in cereals in Europe. Random and systematic monitoring of this weed might provide an early warning for the farmers and slow down the pace of the evolution of herbicide resistance. This study aimed to identify resistant populations of T. inodorum in the Czech Republic and elucidate their possible resistance mechanism/s. Monitoring and screening of T. inodorum for herbicide resistance against acetolactate synthase (ALS) inhibitors and synthetic auxins was carried out. Greenhouse experiments and molecular-genetics studies were conducted to characterize the resistance. While all the tested populations were found to be susceptible to synthetic auxins, two populations (MATIN 2 and MATIN 4) were found to be resistant against tribenuron (ALS inhibitor). However, their cross-resistance to florasulam was not confirmed. The resistance mechanism detected was the target-site substitution of Pro197 at the ALS gene. The two populations carried different point mutations: Pro197Ser (MATIN 2) and Pro197Gln (MATIN 4). This is the first study in the Czech Republic to identify the survival mechanism in T. inodorum for resistance to ALS-inhibiting herbicides. Our results from this research will provide basis for resistance management in T. inodorum in the Czech Republic and other countries.

Quantification of soil health dynamics relative to grazing can inform both agriculture and conservation. We conducted an experiment near Lingle, Wyoming, USA, on a semi-arid northern mixed-grass prairie from 2017–2019. Three grazing density treatments (NG – not grazed; MRG – moderate rotationally grazed a herd of 4 Angus heifers, and UHD – ultra-high density rotationally grazed a herd of 33 Angus cow-calf pairs) were replicated four times in a randomised complete block design across twelve – 0.405 ha paddocks. Soil sampling was conducted prior to grazing in June 2017, one-week post grazing in July 2019, and six weeks post grazing in August 2019 and included a suite of forage, ground cover, soil chemical, soil physical, and soil microbiological measurements. Grazing treatment did result in lower vegetation structure but had no effect on any soil variables (P > 0.05). Conversely, the sampling interval was more influential for predicting fluctuations in chemical (15 variables significantly different within at least one treatment) or microbiological (13 variables significantly different within at least one treatment) variables than grazing treatment. The study was conducted in an intact native prairie with initial and final values indicating "Very Good" soil health, including the saturated : unsaturated fatty acid ratio, an indicator of stress.

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.

Previous studies of the effects of elevated CO₂ (eCO₂) concentrations and heavy metal stress conditions on plant growth and physiology have mostly focused on crops rather than vegetables. In this study, we investigated the effects of Cd stress on the growth and antioxidant system of pak choi (Brassica rapa L.), water spinach (Ipomoea aquatica Forssk.), cherry radish (Raphanus raphanistrum subsp. sativus (L.) Domin) and pepper (Capsicum annuum L.) growing in pots under ambient CO₂ (aCO₂) or eCO₂ conditions. In general, Cd stress reduced plant biomass and SPAD values under aCO₂ and eCO₂ conditions; however, the reduction was smaller under eCO₂. Cd stress significantly reduced vegetable superoxide dismutase (SOD) and catalase (CAT) activities under both aCO₂ and eCO₂ conditions; however, the decrease in cherry radish and pepper peroxidase and SOD activities and in pak choi SOD and CAT activities was significantly less under eCO₂. The Cd content of the edible parts of pak choi, water spinach and pepper was significantly lower under eCO₂ than under aCO₂. Our data suggest that eCO₂ concentrations could be beneficial for the growth of some vegetables and reduce the Cd content.

While nutrients are administered through various sources and combinations, herbicides are used for pre-plant and pre-emergence weed control in the tomato fields. Therefore, a study was conducted to understand the effects of nutrient fertilisation through inorganic and organic sources along with farmers practice and the application of three herbicides, namely glyphosate, pendimethalin, and metribuzin, individually or in combinations, on earthworm activity in tomato crops. The herbicides caused a significant reduction in earthworm biomass and escapement to the lower 15 cm depth. Application of pendimethalin and metribuzin to soils inorganically fertilised with major and micronutrients resulted in low survival rates and a high ecological risk quotient. The effect was attenuated when farmyard manure was applied. The study suggests that when 2 to 3 herbicides are applied in succession and combined with inorganic fertilisers as nutrient sources, stringent measures like adding organic nutrient sources, applying the correct herbicide combination, etc., must be followed to reduce their toxicity to earthworms. This helps to protect and sustain earthworm activity and biodiversity in the soil.

The intensification of Alopecurus myosuroides Huds. (black-grass) is becoming a major problem due to its growing resistance to a broad spectrum of acetolactate synthase (ALS)-inhibiting herbicides. Hence, the present study was conducted to evaluate the resistance level of a black-grass population to iodosulfuron plus mesosulfuron and to identify the underlying resistance mechanism. Dose-response studies revealed that the resistance population is 22 times less sensitive to iodosulfuron plus mesosulfuron than the susceptible population. The probable resistance mechanism identified was the target-site substitution of proline (Pro) by threonine (Thr) at the 197^th position of the ALS enzyme. Furthermore, whole plant response bioassay experiments demonstrated that this population is also resistant to pinoxaden, chlorotoluron, diflufenican plus pendimethalin plus chlorotoluron, fenoxaprop and flufenacet plus diflufenican. In summary, the current findings recommend using alternative herbicides in integrated weed management to interrupt the possible evolution of herbicide resistance in these species.

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.

Research was conducted to determine the content of total polyphenols (TP) in table potato tubers obtained in a three-year field experiment arranged as a split-plot design with three replicates. The first experimental factor included two potato cultivars: Oberon and Malaga, the second one being an application of the following biostimulants: PlonoStart, Aminoplant, Agro-Sorb Folium and the herbicide Avatar 293 ZC (clomazone + metribuzin). The polyphenol content of potato tubers was determined in the fresh tuber mass by the spectrophotometric method with the Folin-Ciocalteu reagent. The tuber content of polyphenols was affected by cultivars and test biostimulants. Cv. Malaga accumulated more polyphenols than cv. Oberon. Biostimulants + herbicide significantly increased an accumulation of polyphenolic compounds compared with tubers cultivated in the control unit which was not treated with the test products.

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.

This work aims to differentiate the rural land of Slovakia in view of the possibility of effective sunflower growing. The differentiation is based on pedo-climatic and production-economic parameters. Soil categorisation took into account the correlation between the site properties (soil and climatic conditions) and the biological and agrotechnical requirements of the crops. Sunflower requirements were included in yield databases using software filters such that a given site property excluded or limited sunflower growing, which was reflected in predicted production. The prediction was subsequently interpolated into four suitability categories: soils unsuitable for sunflower growing, less suitable soils, suitable soils and very suitable soils. A map of categories of soil suitability for sunflower growing was created using a Geographic Information System on the distribution of soil parameters in Slovakia. According to our calculation in Slovakia, 18.8% of farmland is very suitable for sunflower growing, 24.9% is suitable, 16.6% is less suitable, and 39.7% is unsuitable for sunflower growing. These categories are characterised and specified in detail in the paper in terms of geographical, soil, climatic, production and economic parameters. The analysis of the actual sowing of sunflowers between 2018 and 2021 showed that 51% of the areas were located in very suitable soils, 32% in suitable, 10% in less suitable soils and 7% in unsuitable soils for cultivation.

The ability to adapt, survive, and compete with weeds of transgenic plants is the necessary evaluation content to release transgenic lines in target regions. We compared weediness and agronomic traits of transgenic maize lines G1F-8 and G1F-19 carrying the mcry1F gene with their near-isogenic maize inbred line Zheng 58 in the wasteland and cultivated field under natural conditions for two consecutive years. The results showed that there was no significant difference identified in the species, quantity, and relative coverage ratio (RCR) of weeds between fields with G1F-8, G1F-19, and Zheng 58, regardless of the sowing pattern in the wasteland. Compared with the vigour of weeds, none of G1F-8, G1F-19, and Zheng 58 showed survival advantages, and all showed weak growth potential with no final grain yield. Meanwhile, no volunteer seedlings were found upon investigation in the following year. The simulated seed overwintering experiment in the wasteland further showed that the three kinds of maize could not germinate in the second year. In cultivated land, G1F-8 and G1F-19 had the same growth stages, plant height, and RCR as Zheng 58 throughout two years. In conclusion, the transgenic lines G1F-8 and G1F-19 exhibited no adaptability risk in Gongzhuling, Jilin, China.

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.

Arachis hypogaea L. is an annual legume that is one of the most consumed plant species. On the other hand, it belongs to one of the most monitored clinically important allergens worldwide. The polymorphism of this species based on allergen coding genes could be useful in its characterisation, but previously, no allergen-based marker techniques have been developed for peanuts. A new type of DNA-based markers of coding regions were used to analyse the variability of 21 peanut accessions – BBAP (Bet v1 based amplicon polymorphism), PBAP (profilin based amplicon polymorphism), and VBAP (vicilin based amplicon polymorphism). All of the used technique provided polymorphic fingerprints and distinguished the analysed peanut accessions. The effectivity of these techniques corresponds to the presence of the allergen homologous sequences that are a part of the A. hypogaea genome. VBAP was the most effective in distinguishing the analysed peanut accessions when compared to the results of BBAP and PBAB. For BBAP, two of the analysed accessions provided the same fingerprinting pattern. The ability of the used markers to detect polymorphisms was comparable, with an average polymorphism information content (PIC) value of 0.47.

Our objectives were to characterise arable weeds of the Czech and Slovak Republic in cereals, especially considering important groups of species: thermophilic, weedy grasses, and rare and endangered species. The three-year phytocoenological survey was conducted from 2006 to 2008 in five climatic regions and eight different soil types. 379 relevés were recorded, and 281 weed species were found. The effects of both the climatic region and soil type were found to be statistically significant. Species richness increased with altitude. Several species were distinctly associated with soil type, from fertile chernozems to less fertile cambisols, while fluvisols were strongly associated with e.g. Calystegia sepium (L.) R. Br. The incidence of species outside their expected regions generally fit two categories: the most pervasive weeds found almost in all climate regions, such as Echinochloa crus-galli (L.) P. Beauv., or rare weeds in higher altitudes than expected, such as Lolium temulentum L. Rare and endangered species were more likely to be found in a colder climate and poorer soils, and this is linked to less intensive management; however, not all endangered arable species can tolerate such conditions. Even though this data is not recently collected, this is still valuable information on the distribution of weedy species, especially concerning the current interest in maintaining biodiversity.

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.

In this study, the effects of ethylenediaminetetraacetic acid (EDTA) and humic acid (HA) chelate applied to soils contaminated with heavy metals on the development, antioxidant defence system, and phytoremediation of forage turnip (Brassica rapa L.) were investigated for the first. Three doses of EDTA (E1: 5 mmol/kg, E2: 10 mmol/kg, E3: 15 mmol/kg) and three doses of HA (HA1: 500 mg/kg, HA2: 1 000 mg/kg, HA3: 2 000 mg/kg) were applied to soils contaminated with heavy metals (Cd, Pb, Zn, and Cr) in the pot. According to experiment results, HA application as chelate to the polluted soil caused a significant increase in the growth of forage turnip. Phytoremediation values of the plant for Cd heavy metal were found to be BCFshoot, BCFroot > 1, and translocation factor > 1. This result proved that forage turnip has Cd accumulating properties. Also, HA application caused a decrease in H2O2 (46%) and malondialdehyde (6%) levels and antioxidative enzyme activity in polluted soil. It has been concluded that humic acid improves the oxidative stress conditions in the plant and is more effective in the development and growth of the plant than EDTA, so that it can be used effectively in phytoremediation studies.

Biochar is a carbonaceous material derived from the pyrolysis of carbon-rich biomass that has attracted increasing research and attention because of its ability to enhance soil carbon storage, increase soil fertility, fix and transform pollutants in soil, and improve the soil environment. These enhancements directly or indirectly affect soil microorganisms’ metabolic activities and community structure. This paper reviews the effects of biochar on soil physicochemical properties, enzyme activities, nutrients, contaminants, and related microbial activities. In addition, this work summarises the possible mechanisms involved in the interaction between biochar and microorganisms and the potential hazards associated with biochar use. Finally, this study aims to provide a theoretical basis for future related research.

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 objectives of this study were to investigate the nitrogen (N) and phosphorus (P) balance fertilization strategy in paddy fields, and to evaluate the effects on N uptake and utilization in rice. In 2017-2018, the experiment was conducted using Deyou4727 hybrid rice with four different P fertilizer levels (0, 30, 60, and 90 kg/ha), marked as P0, P1, P2, P3 in turn, and four different N levels (0, 90, 150, and 270 kg/ha), similarly marked as N0, N1, N2, N3 in turn. The results showed that in the N-insufficient (N0, N1) environments, the P1 treatment increased N uptake and promoted transfer to the grain. However, high-P (P3) application increased the dry matter accumulation than other P levels, but limited the production and translocation of dry matter to some extent. In N-sufficient (N2, N3) environments, P2 level increased crop yield and N use efficiency by 11.35% and 37.01%. Unlike P2, none-P (P0) and high-P levels decreased rice dry matter translocation and transport capacity, which further affected N uptake and utilization in N-sufficient environments. Overall, the combination of the N application rate of 90 kg/ha and P application rate of 30 kg/ha, N application rate of 150, 270 kg/ha, and P application rate of 60 kg/ha had a high yield; strong nutrient accumulation and transfer ability. It was more inclined to balance N and P, which was beneficial to plant N absorption and utilization.

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.

Phosphorus (P) deficiency significantly affects crop productivity, especially legume crops. Therefore, it is important to understand the P-acquisition strategies of different leguminous crops. In this study, we undertook a pot experiment with 11 legume crops (soybean, faba bean, pea, cowpea, common bean, lentil, adzuki bean, chickpea, grass pea, red kidney bean and common vetch) to investigate P-acquisition strategies related to root morphology, organic acid and acid phosphatase exudations, and arbuscular mycorrhizal fungi (AMF) colonisation under low (4.4 mg/kg) and optimal (40 mg/kg) P conditions. The results revealed that P deficiency significantly decreased biomass and P accumulation, root length (10.5%), and root surface area (7.9%), increased organic acid exudation (80.2%) and acid phosphatase activity (16.8%), and did not affect root diameter or root AMF colonisation rate. Principal component analysis revealed a positive correlation between organic acid exudation and acid phosphatase activity, while root length and root surface area negatively correlated with organic acid exudation, acid phosphatase activity and root AMF colonisation rate. P accumulation positively correlated with root length, surface area, and diameter but negatively correlated with organic acid exudation, acid phosphatase activity, and AMF colonisation rate. These findings confirmed the following: (1) legume crops use a P-mobilisation strategy related to organic acid exudation and acid phosphatase activity to acquire P under low soil P conditions; (2) organic acid exudation coincided with acid phosphatase activity to mobilise soil inorganic and organic P, improving P accumulation; (3) a trade-off exists between the P-scavenging strategy related to root morphology traits and mobilisation strategy.

The improvement of rice production to meet food needs for the increasing population is a general problem faced in wetland development for agriculture. The use of industrial waste, such as coal fly ash (CFA), could effectively improve the soil properties of wetlands. In this study, CFA with an amount of 2% (weight/volume) or 240 g was added to 12 L of three different soils collected from the rice fields (peatland, swampland, and rainfed field) in a 15-L pot, and then incubated in the greenhouse for 15 days. The soil pH, concentrations of NH₄⁺-N, NO₃^–-N, exchangeable calcium (Ca) and magnesium (Mg) and available phosphorus in the soil were quantified following the completion of the incubation. Rice seedlings were planted in each pot, and after 90 days, the growth and yield variables were observed. The results showed that CFA application enhanced the concentrations of NH₄⁺-N, NO₃^–-N, and available phosphorus in peatland and swampland, the rice fields that contain high organic carbon (C), which ultimately leads to increasing rice growth and yield. The application of CFA to rice fields containing low organic carbon did not improve available nitrogen and phosphorus nor enhance the growth and yield of rice. Results of this study indicate an important role of soil organic C content in the rice fields in controlling the effect of CFA on nutrient availability, growth and yield of rice.

This study aims to verify the application effect of Fluvic acid (FA) with different molecular weights (MW) on the growth and quality of winter wheat. FA extracted from lignite was divided into 3 MWs (W1≤3000 D, 3000 D<W2≤10000 D, and W3>10000 D) by dialysis, and its structure was analyzed. Three application rates were set for each MW FA in the pot experiment, which were 10, 25 and 50 mg/kg in soil, respectively, and water was the control. There were significant interactive effects of MW and application rates of FAs. Compared with the control, all the FA treatments significantly increased grain yields, nitrogen uptake efficiencies, grain iron concentration, and soil available nitrogen concentration. Heatmap analysis revealed that the W1C2 (10 mg/kg W1) treatment had the most significant impacts for all analyzed indexes, whereas W3C3 (50 mg/kg W3) showed the weakest impacts. The results showed that at a low application rate (10 mg/kg in soil), the promotion effects of the three MW FAs were similar. W1 showed the most significant promotion effects, which was attributed to the combined effects of its lower MW and functional group characteristics.

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.

One of the latest environmentally friendly methods in soybean production technology is the pulsed electromagnetic field of low frequencies (PEMP). The paper presents the results of the influence of electromagnetic stimulation of soybean seeds on grain yield, protein and oil yield, depending on different agroclimatic conditions, exposure time and frequency. In the 2012–2017 research period, the soybean cv. Valjevka was used in the Institute of Field and Vegetable Agriculture experimental field, Novi Sad, Serbia. Immediately before sowing, the seeds were subjected to PEMP treatment, with a pulse generator and a tape applicator, in the following variants: electromagnetic field frequencies of 16, 24 and 30 Hz, and exposure time of 0, 30 and 60 min. The most successful variant of seed stimulation for all three examined parameters was at 16 Hz and 30 min, where the research results show that this measure can increase the examined parameters by more than 10%. The average yield of grain for all years of research with seed stimulation was 4.85% (3 338 kg/ha) compared to the control (3 203 kg/ha). The average grain protein yield in the treatments with PEMP was 1 315 kg/ha, which was 4.26% higher compared to the variant without PEMP (1 260 kg/ha), and the treatment was 4% higher in the average oil yield, 703 kg/ha compared to the control 676 kg/ha. Also, the analysis of the mutual dependence of the indicators is in a positive correlation, which is essential for plant breeding and the development of new technologies, which have economic justification, are safe for use and have a positive impact on adverse effects such as drought.

The present study reports on research results obtained in the years 2014-2015 on two sugar beet production plantations in Central Poland. The purpose of any production is to obtain homogeneous canopy with the plants of demanded morphological and qualitative traits. The aim of the research was the assessment of the range and scale of plant variability in sugar beet canopy and impact of investigated plant and canopy traits (number of days from sowing to emergence, development stage of plants in the juvenile period, the plant living area, the location centrality index) to the final root mass at harvest time. Variability of investigated plant and canopy traits was evaluated using the variation coefficient, while the impact of these traits on the final root mass was assessed using the analysis of multiple linear regression. The obtained results show that sugar beet canopy reveals large, within-field variability in the investigated traits. The established relationship between final root mass during harvest and the canopy traits indicates that to obtain a large final root mass of individual plants during harvest, the most important is fast and even plant emergence, as well as the rapid development of plants in the juvenile period. At both production plantations, the impact of the living area of individual plants on the final mass of their roots was significant. However, no significant effect of the location centrality index on plant living area and the final root mass was found.

The present work aimed to analyse whether and how single or dual inoculation with arbuscular mycorrhizal fungi (Funneliformis mosseae, Paraglomus occultum, and Rhizophagus intraradices) and rhizobia (Rhizobium trifolii) improved plant growth and stimulated nitrogen (N) acquisition of white clover. AMF inoculation significantly (P < 0.05) increased root nodule number by 117‒173%, and additional Rh considerably stimulated mycorrhizal growth. Single AMF or Rh treatment dramatically increased shoot by 36‒281% and root biomass by 16‒36% than non-inoculated control, and dual inoculation of Rh and P. occultum or R. intraradices further magnified the positive effect. Leaf and root N content, root total soluble protein content, root nitrogenase activity, and amino acid (e.g., alanine, arginine, asparagine, aspartate, phenylalanine, proline, and tryptophan) concentrations were significantly increased by single or dual inoculation, while dual inoculation of AMF and Rh had significantly superior roles than single corresponding AMF or Rh inoculation. These results suggested that AMF and Rh represented synergetic effects on accelerating N acquisition of white clover to some extent, while the combination of P. occultum and Rh was the best.