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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.

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.

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.

In this study, three insect-resistant transgenic Bacillus thuringiensis (Bt) oilseed rape events (GT1, GT5 and GT9) under field conditions were utilised to analyse the dynamics of Cry1Ac protein and the changes in soil enzyme activities in the rhizosphere soil of transgenic Bt plants during different growth stages over two successive cultivation years. The results indicated that compared to the non-transgenic control plant cv. Westar, the amount of Cry1Ac protein in the rhizosphere soil of the three transgenic oilseed rape events was significantly higher during the flowering and podding stages in the first cultivation year. Additionally, in the second cultivation year, transgenic GT1 and GT9 had significantly higher amounts of Cry1Ac protein in the rhizosphere soil during the flowering stage, and all three transgenic oilseed rape events had significantly higher amounts of Cry1Ac protein in the rhizosphere soil during the podding stage. Over the two successive cultivation years, the sucrase activity in the rhizosphere soil of transgenic events showed significant changes during bolting, flowering and podding stages, while all three transgenic events exhibited significant changes in phosphatase activity during the four different stages. Furthermore, different transgenic events showed varying significant changes in urease and protease activities during the bolting, flowering and podding stages of the first year, and all three transgenic events had significant changes in dehydrogenase activities during the four different stages of the second cultivation year. PCA and correlation analysis clearly demonstrated a strong correlation between the Cry1Ac protein and five soil enzyme activities, as well as a close interconnectedness among those five soil enzyme activities. These findings suggest that the amount of insecticidal crystal proteins in the rhizosphere soil of transgenic Bt (Cry1Ac) oilseed rape varies with different growth periods, and the enzyme activities in the rhizosphere soil of transgenic Bt oilseed rape plants undergo significant changes over two successive planting years.

Potato (Solanum tuberosum L.) is a plant typical mainly for temperate climate and develops best at about 20°C. Heat stress due to increased temperatures is an agricultural problem in many areas in the world. The aim of our work was to assess the response of selected new potato cultivars to heat and drought stress during the subsequent stages of plant growth starting from buds forming. The pot experiment was carried out over the course of two years with the following early cultivars: Lord, Miłek, Gwiazda, Hubal, Oberon and Tetyda. The impact of heat (38°C/25°C) and drought stress on potato plants was tested in four periods of two weeks. In these periods half of the plants were watered to a level close to optimal while the other half remained without irrigation. Our studies demonstrated that tested potato cultivars' response to heat stress depends on the growth stage, in which the temperature acts on the plants and on the soil moisture. Besides the decrease in yield and tubers' diminution, the biggest problem was the presence of tubers with physiological defects, particularly of immature tubers. The response of cultivars was differentiated.

In a pot experiment, arsenic-hyperaccumulating Pteris cretica cv. Albo-lineata plant ferns were cultivated and exposed to low and high doses of arsenate (20 and 100 mg As/kg, respectively) for six months. Physiological and morphological changes of roots, as well as changes in soil quality of the root zone and bulk soil (water-soluble fraction of elements and activity of soil enzymes), were determined. The results showed that the accumulation of inorganic As, mainly in the form of As3+, did not significantly affect the yield of roots, but caused changes in root morphology (deformation of root cell walls due to lignification) and metabolism (decrease of auxin indole-3-acetic acid and 2-oxoindole-3-acetic acid contents). Although the soil quality results varied according to the As dose, there was a clear difference between the root zone and the bulk soil. The activities of enzymes in the root zone were greater that those in the bulk soil. The results showed a significant influence of the high dose of As (100 mg As/kg), which decreased the activity of arylsulfatase, nitrate reductase, and urease in the root zone, while a decrease in acid phosphatase and nitrate reductase was observed in the bulk soil. The water-soluble fractions of As, organic nitrogen, nitrate nitrogen and organic carbon were significantly affected by the high dose of As.

The effect of individual nanometals (Co, Fe, Cu, Ge) carboxylates (NMC) as components of the suspension for seeds inoculation with rhizobia on the nitrogen fixation rate and the parameters of CO2 and H2O gas exchange in soybean plants grown under different water conditions was investigated. The scheme of trials included the following variants: 1 - seeds + strain B1-20; 2 - seeds + (strain B1-20 + nano-cobalt carboxylate); 3 - seeds + (strain В1-20 + nano-ferrum carboxylate); 4 - seeds + (strain B1-20 + nano-cuprum carboxylate); 5 - seeds + (strain B1-20 + nano-germanium carboxylate). The results showed that during the flowering period, drought (30% field capacity) significantly reduced the rates of nitrogen fixation (Nfx), CO2 net assimilation (An), and transpiration (Tr) in soybean plants. Inoculation of seeds by rhizobia with NMC before sowing reduced the negative effect of drought on these physiological processes. Close correlations were found between the rates of Nfx and An and the stomatal conductance for CO2 and An rates. It was concluded that pre-sowing treatment of seeds by rhizobia with NMC mitigates the negative effect of drought on the main components of soybean-rhizobia symbiosis productivity formation - nitrogen fixation and CO2 assimilation, and also contributes to their recovery after the removal of the stressor. The most effective for this was the use of Ge and Fe nanoparticle carboxylates.

Today, there is widespread concern about the potential health effects on populations from consuming contaminated leafy plants and vegetables. In this study, heavy metal content is present in commonly consumed leafy plants (Atriplex hortensis, Spinacia oleracea, Urtica dioica, Beta vulgaris, and Brassica oleracea) from the mining area near Tuzla in Bosnia and Herzegovina was determined. After the preparation of the samples by wet digestion with HNO3, the flame and graphite furnace atomic absorption spectrometry was used. According to the results, the lowest concentration in leafy plants was obtained for Cr 0.08 mg/kg (Brassica oleracea) and the highest for Fe 539.15 mg/kg (Spinacia oleracea). The novelty of this study was to estimate health risk assessment for selected leafy plants. The estimated daily intake (EDI) of Pb, Mn, Zn, and Cd from consuming leafy plants was higher than the maximum tolerated daily intake. For adults, the total target hazard quotient (THQ) calculated based on EDI of the heavy metals was found to be > 1 for Pb and Cd due to all leafy plant consumption and for the children risk level of THQ was observed for most heavy metals. The hazard index due to the intake of toxic metals from ingesting leafy plants was much > 1. According to the total carcinogenic risk index for adults and children, the carcinogenic risks for all samples were higher than the tolerable range. Based on the results of this study, there is a significant non-carcinogenic and carcinogenic health risk to the population associated with the consumption of leafy plants cultivated in the mining area.

To supply more insights into the roles of putrescine (Put) in alleviating salt stress in wheat crops, we explored the effects of Put on ascorbate (ASC) and glutathione metabolism, photosynthetic performance, and ion homeostasis in leaves of salt-stressed wheat seedlings. Our results displayed that salt stress increased the activities of enzymes in ASC and glutathione metabolism, including ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, glutathione reductase, gamma-glutamylcysteine synthetase, and l-galactono-1,4-lactone dehydrogenase, which increased reduced ascorbate (AsA), dehydroascorbate (DHA), reduced glutathione (GSH), oxidised glutathione (GSSG), total ASC and total glutathione contents. Whereas, salt stress induced higher increases in the contents of DHA and GSSG than those of AsA and GSH, which led to reduced AsA/DHA and GSH/GSSG. Meanwhile, salt stress reduced photosynthetic rate (P_n), maximum photochemical efficiency of PSII (F_v/F_m), and the contents of chlorophyll and carotenoids, and destroyed Na⁺/K⁺ homeostasis, which further inhibited plant growth. In comparison with salt stress alone, Put strengthened the activities of the above enzymes, which further increased the above metabolites contents, as well as AsA/DHA and GSH/GSSG in leaves of salt-treated seedlings. In this way, Put reduced malondialdehyde content and electrolyte leakage. Besides, Put also increased P_n, F_v/F_m, and above pigments contents, and maintained Na⁺/K⁺ homeostasis. Meanwhile, Put increased plant height and biomass of salt-treated seedlings. The present findings clearly implied that Put enhanced salt tolerance of wheat crops by strengthening ASC and glutathione metabolism, photosynthetic performance, and maintaining ion homeostasis in leaves. Therefore, Put can be applied to strengthen the salt tolerance of wheat crops in production and cultivation.

It is well known that mechanochemically activated phosphate rock (MAPR) could improve extractable phosphorus (P) (extracted in 2% citric acid) greatly in an ecological way. To evaluate the agronomic effectiveness of MAPR, we conducted a field experiment using spring maize in Luvisol (pH 6.47) soil in Northeast China for three consecutive years. Treatments consist of variation of P levels for substitution of triple superphosphate (TSP) (100% TSP, 10% MAPR, 20% MAPR, 50% MAPR, 100% MAPR). Compared with 100% TSP, all the combined applications of MAPR and TSP were as effective on straw yield. Treatments of 10% MAPR and 20% MAPR had similar effect on grain yield and P uptake, while 50% MAPR and 100% MAPR were significantly lower. For P partial nutrient productivity and apparent P recovery with the treatment of 20% MAPR had equal effectivity, likewise. For soil P_Olsen, treatment of 10% MAPR was equally operative, while 20% MAPR had the similar performance only in the last year (i.e. 2016). It is concluded that 10-20% of TSP can be effectively replaced by MAPR without affecting spring maize yield in soil with neutral pH.

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.

Agronomic bio-fortification is one of the main approaches for mitigation of micronutrient shortage in human populations and endorses sustainable production of food and feed. Studies related to agronomic bio-fortification of crops are mainly focused on single or rarely two micronutrients application, and no attempt has made to study the combined effect of zinc (Zn), iron (Fe) and selenium (Se) on forage sorghum. Therefore, this research was accomplished to evaluate the effect of Zn, Fe and Se bio-fortification on diverse sorghum accessions. The field experiments were conducted in a randomised complete block design with a split-plot arrangement. The treatments comprised of Zn (10 mg/L as ZnSO₄∙5H₂O), Fe (7 mg/L as FeSO₄∙7H₂O), Se (3 mg/L as SeSO₄) and CK (control) were applied to five sorghum accessions: G₁ (Y-16), G₂ (YSH-166), G₃ (YSH-134), G₄ (YSS-98) and G₅ (YSH-132). According to our results, the sorghum accession G₅ showed superiority over all other accessions and produced maximum values of all growth and quality traits except grains number per panicle and 1 000-grain weight. All applied micronutrients (Zn, Fe and Se) enhanced the growth, quality and uptake of nutrients in sorghum accessions. However, Se recorded the highest plant height, stem diameter, 1 000-grain weight and Zn produced the maximum protein, oil and starch contents. Conclusively, it can be concluded that G₅ with Se must be used to achieve the optimum values of agronomic traits, while G₅ with Zn found more effective to improve the quality traits of sorghum.

This study aimed to characterise the specific phenotypic responses and the sensitivity of photosynthetic parameters to progressive drought in modern wheat genotypes. In pot experiments, we tested eight wheat genotypes (Triticum sp.) that differed in ploidy level and country of origin. Water stress was simulated by the restriction of irrigation, which led to a decreased leaf relative water content of up to 70%. During gradual dehydration, changes in the structure and function of photosystem II (PSII) were analysed using the fluorescence parameters derived from fast fluorescence kinetics (OJIP transient). The results indicated that a group of JIP test-based parameters demonstrated sensitivity to drought, including genotype-specific responses. Severe drought stress led to a decrease in the photochemical efficiency of PSII (Fv/Fm), a reduction in the number of active PSII reaction centers (RC/ABS) and a decrease in parameters, indicating overall photochemical performance at the PSII level (performance indices PIabs and PItot). These findings demonstrate that the approaches used in our experiments were useful and reliable in monitoring the physiological responses of individual varieties of wheat exposed to stress conditions, and they have application potential as selection criteria in crop breeding. The contribution of the high-temperature effects on the photochemical responses under water deficit conditions is also discussed.

Water and nutrient use efficiencies are important adaptive features of plants in arid and semi-arid environments. In this study, water, nitrogen (N), and phosphorus (P) use efficiencies of Stipa purpurea Griesb., an endemic and dominant grass species, were investigated in the alpine steppe along precipitation gradients on the Tibetan Plateau. The leaf N content of S. purpurea increased along the precipitation gradient, but leaf P decreased, whereas carbon (C) remained unchanged. Leaf δ¹³C (water use efficiency, WUE) and C : N ratio (N use efficiency, NUE) decreased with increasing precipitation. But leaf C : P (P use efficiency, PUE) and N : P ratios increased with increasing precipitation. A trade-off was found between WUE and PUE but not between WUE and NUE. The changes in leaf traits were associated with changes in soil water, organic C, total N and P. These findings offer insights into understanding alpine plant water and nutrient use strategies along a precipitation gradient, as well as facilitate the prediction of alpine ecosystem responses to precipitation changes.

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.

The aim of the study was to determine the effect of water deficiency at different development stages on the bioactive content and phenolic compounds in sunflower (Helianthus annuus L.) cake, the residue left after oil is extracted from sunflower seeds. A sunflower genotype was randomly planted in a complete block design with eight different combinations of irrigation (T1–T8) by increasing the available soil moisture measured at different plant growth stages (vegetative, flowering and grain formation). Results indicated that the total phenolics of extracts varied between 1.03–2.03 times more than under drought stress (T8). The antioxidant capacity response of seed cake was 14–39% lower than under drought stress. Irrigation treatment, except in the grain formation stage, was found to enhance the biosynthesis of phenolic compounds such as vanillic and caffeic acids. Irrigation only in the grain formation stage induced the accumulation of phenolic compounds such as coumaric acid and rutin hydrate. The present study established that residues resulting from oil extraction could be converted to a polyphenol-enrichment agent for food systems by manipulating the irrigation treatments.

Changing political demands requires the search for alternatives to glyphosate, which has often been used in the stale seedbed method. In three field trials between 2020 and 2023, three electrophysical treatments (XPower System, Zasso®) differing in speed, three mechanical treatments (disc harrow, rotary harrow, cultivator) and three chemical treatments (glyphosate, maleic hydrazide, pelargonic acid + maleic hydrazide) were evaluated concerning the efficacy and economic performance in stale seedbed method in Alopecurus myosuroides control. Process costs for each treatment were calculated. Furthermore, the maximum investment costs for the XPower system were calculated to be on the same level as the other treatments. In all treatments, the density of A. myosuroides in autumn was significantly lower than in the control. In general, the fewest plants and heads were found in the chemical treatments. Despite the lower plant density, the electrophysical method did not show a significant difference in the number of heads compared to the untreated control, especially at higher speeds. Calculated process costs ranged between
40 €/ha (glyphosate) and 430 €/ha (pelargonic acid + maleic hydrazide). To be economically comparable with the other treatments, the investment of the XPower should be at maximum between – 219 000 € (glyphosate) and 300 000 € (pelargonic acid + maleic acid), depending on the driving speed. In a holistic view, electrophysical control, as well as pelargonic acid and maleic hydrazide as glyphosate alternatives in the stale seedbed method, are not suitable. A stale seedbed with mechanical control of A. myosuroides is recommended.

Biochar-based fertiliser (BF) is beneficial to improve yield and quality, but the effect of BF on open field tomato remains unclear, especially in karst mountainous areas. The objective of this study was to identify the application effect and optimum application rate of BF. A field experiment was carried out in Southwestern China from 2019 to 2020 to study the effects of different application amounts of BF on the yield, quality, nutrients accumulation and fertiliser utilisation of open field tomatoes. The results showed that compared with the traditional fertilisation practice, BF can significantly increase the yield of open field tomato by 5-9% (2019) and 12-23% (2020), and significantly reduce nitrate content and increase vitamin C content of fruits. Meanwhile, nutrient accumulations, agronomic efficiency, and recovery efficiency of BF treatments were all significantly improved. In conclusion, the BF rate of 2 326 kg/ha improves yield and fertiliser utilisation in open-field tomatoes and could be recommended for tomato production in karst mountainous areas.

This study evaluated the effect of seed weight and seed treatment on yield and growth parameters in a three-year field trial. Seed weight treatments were tested in three levels of thousand seed weight (TSW): low 4.28 g, medium 5.00 g and high 5.69 g, with and without a biostimulant seed treatment of Lumibio Kelta. Although statistically significant differences were not found in all experimental years, the three-year results showed that sowing seeds with higher seed weight increased the initial and final stand counts, root length, seed yield and oil content. The final stand at harvest time averaged over the three years ranged from 23.0 (low TSW) to 29.5 plants per 1 m² (high TSW). Plants from high TSW seed had an average of 1.1 cm longer roots than plants from low TSW seed. The average yield increased with TSW: 5.49 t/ha (low TSW), 5.86 t/ha (medium TSW), and 5.94 t/ha (high TSW). High TSW also yielded higher oil content (45.77%) compared to the medium (45.25%) and low TSW (45.27%). No statistical difference could be detected in the initial emergence counts or final seed quality according to seed treatment. Seed treatment with the biostimulant increased root length and seed yield. Plants from seeds treated with the biostimulant had roots with an average of 0.6 cm longer, yielding 0.2 t/ha higher than the non-treated ones.

Biochar is considered as a soil amendment for enhancing crop productivity. However, limited information is available on the residual effect of biochar application on rice grain yield and yield attributes. In this study, a fixed field experiment was conducted in a double rice-cropping system from 2017 to 2019. The dynamics of rice grain yield and yield attributes were monitored in the six growing seasons with 0, 20, and 40 t/ha biochar application. The results showed that the averaged grain yields in the first four seasons were increased by 2.56-16.84% and 6.15-10.77% with 20 and 40 t/ha biochar application. The trend of increased grain yield in rice with biochar application during the first seasons was mainly attributable to an increase in total biomass, panicles per m2 and spikelets per panicle. Nonetheless, the grain yields in the sixth season were not influenced by biochar addition due to decreases in panicles per m2 and spikelets per panicle. Thus, it can be seen that the positive effects of biochar application on rice yield and yield attributes depend on the duration of biochar application.

This study identified three soil bacteria (NRRU-BW3, NRRU-BW3, and NRRU-TV11) that degrade chlorpyrifos, produce indole-3-acetic acid, and exopolysaccharides under pesticide stress. The results revealed that soil bacteria were identified as Priestia megaterium NRRU-BW3, Bacillus siamensis NRRU-BW9, and Bacillus amyloliquefaciens NRRU-TV11. These strains showed the ability to produce indole-3-acetic acid (IAA) and exopolysaccharides (EPS) in chlorpyrifos. Moreover, these bacteria can degrade chlorpyrifos (CP) in an aqueous medium, and a 33–52% degradation rate was observed after 14 days of incubation. Inoculation with the NRRU-TV11 significantly increased (P < 0.05) plant height, root length, biomass and vigour index of rice seedlings compared to uninoculated controls in chlorpyrifos-contaminated soil. The findings demonstrated the beneficial effects of indigenous NRRU-TV11 on rice seedling development and chlorpyrifos degradation and recommended this strain as a potential replacement for plant growth improvement and environmental bioremediation of pesticide-contaminated agricultural soils.

Soil pH can affect the adsorption of mesotrione and exacerbate crop injury under non-acidic conditions. Soil samples collected from the same location were irrigated with water solutions of pH 7.5, 6.5, 5.5, and 4.5 and treated with 72, 36, 24, 18, 9, 4.5, 2.3, and 1.1 g a.i. (active ingredient) of mesotrione/ha. Bean growth was monitored over 28 days. Soil pH solution did not influence the effect of mesotrione on plant fresh weight, while herbicide-induced visual injury and reduction in carotenoid content were significantly mitigated under acidic conditions. The lowest rate (1.1 g a.i./ha) applied in slightly acidic soil (pH 6.5) caused visual injury of 45% 28 days after treatment, while visual injuries on plants grown in soils with pH 4.5 were only 20%. Further, bean plants grown at pH 4.5 showed only 3.3% lower carotenoid content compared to control plants since for those grown in a slightly alkaline environment (pH 7.5) reduction of this pigment was 35.5%. The mean effective dose (ED50 ± standard error) of mesotrione for inhibition of carotenoids were 5.25 ± 0.61 g a.i./ha at pH 7.5, 9.57 ± 0.74 g a.i./ha at pH 6.5, 13.07 ± 0.91 g a.i./ha at pH 5.5, and 14.98 ± 0.94 g a.i./ha at pH 4.5. Results indicate that the common bean is highly susceptible to the presence of mesotrione residue and that this sensitivity strongly depends on soil pH solution.

Polyphenols and carotenoids are important bioactive compounds in potato tuber. Knowledge of these features makes it possible to select cultivars for cultivation, consumption, and processing with desirable properties. For this purpose, the content of polyphenols and carotenoids in edible potato tubers from different countries was analysed. The research material consisted of eight cultivars, including one light yellow – Eurostar, two with red flesh – Rote Emmalie and Herbie 26 and five cultivars with purple flesh – Provita, Salad Blue, Blue Annelise, Vitelotte Noire and Bora Valley. They were cultivated in a three-year, single-factor field experiment. The content of polyphenols in the analysed cultivars ranged from 165.0 to 283.8 mg/kg of fresh weight and depended on the cultivar, year of research and cultivar-year interactions. The highest average amounts of these compounds were noted in the Herbie 26, Rote Emmalie and Vitelotte Noire cultivars. The content of carotenoids ranged from 1.122 to 3.173 mg/kg of fresh weight and depended significantly on the cultivar, weather conditions in the years of the study and the interaction of cultivars with years. The highest amounts of carotenoids were determined in the purple-fleshed cultivars Blaue Annelise and Vitelotte Noire and the red-fleshed cultivar Rote Emmalie.

A field experiment was conducted on rendzina soil in the years 2010-2012. The seeds of two linseed cultivars (Szafir and Oliwin) were sown at row spacing of 15 cm and 25 cm. Three agrotechnical levels in different nitrogen doses and with or without application of herbicides were used. The objective of the study was to evaluate the effect of row spacing on yield, seed protein and oil content of two linseed cultivars grown under different conditions of mineral fertilization and chemical weed control. Results showed that cv. Szafir was characterized by significantly higher seed yield (on average by 20.2%) and protein content (by 2.6%) while cv. Oliwin had higher content of oil (by 4.9%). Intensive technology of cultivation (80 kg N/ha, Linurex 50 WP, Fusilade Forte 150 EC, Glean 75 WP), compared to the economical technology (40 kg N/ha, without herbicides), significantly increased the seed yield of both linseed cultivars (on average by 80-102%). This was due to higher plant density, higher number of branches, and higher number of capsules per plant. The intensive technology of cultivation had a beneficial effect on the content of α-linolenic acid in linseed seed.

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.

The effect of drought stress on carbon metabolism in the leaves and roots of bermudagrass was investigated. Plants established in PVC tubes suffered from three water treatments for 10 days. C138 and Tifway (drought-tolerant) were found to have lower relative electrical conductivity and higher water use efficiency than C32 (drought-sensitive) under moderate drought by increasing carotenoid and soluble sugar content and rapidly decreasing leaf starch content. The sucrose synthase activity of leaves and roots, acid invertase and neutral invertase activity of C32 roots substantially decreased under severe drought, resulting in a slow sucrose decomposition rate and significantly lower fructose and glucose contents than C138 and Tifway. The activities of four carbon metabolism enzymes and sucrose content in the leaves were greater than those in the roots, while the fructose and glucose contents were on the contrary, indicating that bermudagrass transported fructose and glucose obtained from sucrose decomposition from leaves to roots under drought to reduce roots damage. The path analysis indicated that leaves neutral invertase activity, and roots soluble sugar content might be the key parameter of carbon metabolism in bermudagrass under drought.

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.

Genetically modified (GM) crops have brought huge economic benefits to mankind, however, at the same time, their safety issues are drawing growing attention. This investigation was conducted to assess whether the long-term cultivation of GM glyphosate resistant maize CC-2 effects bacterial communities in the rhizosphere soil. A 2-year follow-up trial was conducted, and soils were sampled at various plant developmental stages. The bacterial community structure of the rhizosphere soil was analysed by the high-throughput sequencing and compared with the near-isogenic non-GM maize Zheng 58. We showed here that long-term cultivation of CC-2 has no significant effect on the structure and diversity of bacterial communities, while different growth stages had significant effect. These results provided a reliable theoretical basis for the future cultivation and increased commercialisation of CC-2.

Soil carbon transformation was observed in long-term stationary field experiments (longer than 20 years) at two sites with different soil-climatic conditions (Luvisol, Chernozem). The following crops were rotated within the trial: row crops (potatoes or maize)-winter wheat-spring barley. All three crops were grown each year. Four different fertilization treatments were used: (a) no fertilizer (control); (b) sewage sludge (9.383 t dry matter/ha/3 years); (c) farmyard manure (15.818 t dry matter/ha/3 years); (d) mineral NPK fertilization (330 kg N, 90 kg P, 300 kg K/ha/3 years). At the Luvisol site, the control treatment showed a tendency to decrease organic carbon (C_org) in topsoil. At organic fertilization treatments the content of C_org increased: sewage sludge - +15.0% (Luvisol) and +21.8% (Chernozem), farmyard manure - +19.0% (Luvisol) and +15.9% (Chernozem). At the NPK fertilization, the increase was +4.8% (Luvisol) and +4.7% (Chernozem). The increased C_org content was also associated with an increase of microbial biomass carbon (C_mic) and extractable organic carbon (0.01 mol/L CaCl₂ and hot water extraction). The ratio of C_mic in C_org was within the range 0.93-1.37%.

Cultivating crops influences soil organic matter (SOM), but the effect of different crops remains unclear, particularly under long-term monocropping. The objective of this study was to identify how different crops influence the content and chemical structures of SOM under long-term monocropping. Here, soils were sampled (0-20 cm) under 27-year soybean and maize monocropping and separated into different physical fractions. The content and chemical structures of SOM in all fractions were determined. SOM contents were higher under soybean than maize in bulk soil and macroaggregates and their light-fractions instead of microaggregates and silt and clay. The difference in SOM chemical structure was observed in aggregates and density fractions rather than bulk soils and supported by the result of principal component analysis. The proportion of O-alkyl C in macro- and microaggregates and all free light fractions and that of aromatic C in mineral-associated fractions were higher, while that of carbonyl C was lower under maize than soybean. These results demonstrated that different crops monocropping influences the content and chemical structures of SOM, and the variations were mainly in the light-fraction SOM and highlight a higher sensitivity of physical fractions than bulk soil to different crops.