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The production of Moringa oleifera L. using sustainable and accessible regional inputs constitutes an alternative to boost its cultivation in tropical environments. This study aimed to evaluate the production of M. oleifera seedlings cultivated in substrate constituted of different proportions of organic compost and soils. The treatments consisted of substrates obtained from five proportions of organic compost from tree pruning and bovine manure (0:100; 20:80; 40:60; 60:40, and 80:20 v/v of organic compost and soil). After 120 days of sowing, the following evaluations were carried out: root length, plant height, stem diameter, aerial part dry matter mass, roots, total and their relationships, chlorophyll A, B and total, Dickson Quality Score and accumulations of nitrogen, phosphorus and potassium in the aerial part dry matter mass. The application of different proportions of organic compost for the formulation of the substrate stimulated the growth of M. oleifera seedlings for all the variables analyzed. The dose of organic compost that provided greater responses based on Dickson Quality Index was 73% of organic compost added to the soil to form the substrate and therefore recommended for the production of M. oleifera L. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With increasing global water scarcity, the reuse of treated wastewater for agricultural irrigation offers a promising solution, particularly in arid regions. This study evaluates the impact of distillery wastewater from Kinmen Kaoliang Liquor Inc. (KKL) on the growth of wheat and sorghum in the Kinmen region. The field experiment applied varying proportions of KKL wastewater to assess its effects on soil properties, nutrient distribution, and crop performance. The results showed that wastewater irrigation increased soil concentrations of key nutrients, such as potassium (K), sodium (Na), magnesium (Mg), and phosphorus (P), but also raised the electrical conductivity (EC) and sodium adsorption ratio (SAR) beyond acceptable irrigation standards. K, Mg, Ca, and P primarily accumulated in the stems and grains, while Na was concentrated in the roots. However, higher wastewater concentrations negatively affected soil permeability due to Na accumulation, and elevated salinity levels led to reduced plant biomass. This study concludes that although wastewater irrigation improves nutrient availability, careful management is essential to mitigate salinity risks and ensure sustainable agricultural practices. These findings offer valuable insights into the potential of wastewater reuse in water-scarce regions and provide practical recommendations for managing associated risks. [ABSTRACT FROM AUTHOR]

Wheat nutritional quality can be characterised by nutrient concentrations in the grain. This is the sum of nutrient uptake by the roots and re-translocation from other organs during grain filling. It is quantified by the Nutrient Harvest Index (NuHI: the fraction of total accumulated nutrient that is allocated to the grain). In contrast to nitrogen (NHI), there has been little quantification of NuHIs among modern hard spring wheat genotypes, when grown under contrasting N supply. We investigated NuHIs for six macro- and four micro-nutrients among six hard spring wheat genotypes, both under field and glasshouse conditions. There was consistency in element-specific NuHI values between experiments and amongst genotypes. Values ranged from 0.09 to 0.86, with highest NuHI found for phosphorus (P; 0.86) and N (0.82) and lowest values (<0.25) for calcium, copper, iron and potassium. NuHIs were higher under low N supply for all elements, except P, manganese and zinc, which were unaffected by N supply. This reflects the greater deposition of carbohydrate in higher yielding (N fertilised) crops. Thus, NuHIs for the hard spring wheat genotypes tested were highly element specific, and decreased with N supply within a given environment. HIGHLIGHTS: Nutrient Harvest Index (NuHI) was similar between field and controlled environment NuHIs were consistent across six modern spring wheat genotypes NuHIs were in large element-specific ranging from 0.09 for potassium to 0.86 for phosphorus Limited N supply increased NuHIs mainly through reduced grain yield [ABSTRACT FROM AUTHOR]

Cropland acidification seriously restricts sustainable agricultural development. The main purpose of this study was to determine whether deeper tilling could alleviate topsoil acidification to improve the quality of arable land. A soil column incubation experiment simulating tillage depths (10 cm, 30 cm and 50 cm) and lime addition was conducted to determine their effects on soil acidification improvement. The changes in soil pH, exchangeable acidity, ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3−-N), available phosphorus (AP), and microbial phospholipid fatty acids (PLFA) were analyzed. Tillage depth, lime application, and their interaction all had significant impacts on soil pH. T50 (simulated tillage depth of 50 cm) and T50+Lime (simulated tillage depth of 50 cm plus lime) treatments significantly increased the topsoil pH from 5.41 to 6.35 and 7.12, respectively. T50 treatment significantly reduced the soil exchangeable acid content compared to the T10 treatment. The nutrient accumulation along soil column indicated that the T50 and T50+Lime treatments significantly increased NO3−-N and AP content in the >30–50 cm soil layer. Compared with T30, NO3−-N accumulation in the >30–50 cm soil layers of T50 and T50+Lime treatments was 6.62 and 7.93 times higher, respectively. The accumulation of AP in the >30–50 cm soil layers of the T50 and T50+Lime treatments was 1.33 and 1.54 times higher than in the T30 treatment, respectively. These findings imply tillage up to 50 cm without exogenous materials could be a potential measure to reduce topsoil acidification and increase nutrition availability of >30–50 cm soil layers. Tillage of up to 30 cm combined with lime application confers greater benefits, which would particularly impact crops with shallow root systems. Subsequent field experiments will be conducted to further investigate the efficacy of these strategies in enhancing crop yield. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examined the effect of organic fertilizer replacing the chemical fertilizer ratio on barley yield, nutrient utilization, and soil properties to provide a theoretical basis for reducing chemical fertilizer application in barley, increasing yield and efficiency. considering“Kunlun 14”barley as the test material, seven experimental treatments were set up：no fertilization (CK), conventional fertilization (CF), organic fertilizer substitution of 20% (T1), 40% (T2), 60% (T3), 80% (T4), and 100% (T5) . The effect of the organic fertilizer substitution ratio on barley yield, dry matter accumulation, nutrient accumulation, fertilizer utilization, soil physicochemical properties, and enzyme activity under equal nutrient inputs was studied. Barley yield, dry matter accumulation, nutrient accumulation, and fertilizer utilization gradually decreased with the increase in the organic fertilizer substitution ratio. T1 treatment significantly increased barley yield, nutrient accumulation, and fertilizer utilization compared with CF. The organic fertilizer replacement treatment increased soil organic matter and nitrate nitrogen content, decreased soil pH and ammonium nitrogen content, and had no significant effect on soil total nitrogen content compared with CF. The T1 treatment increased the soil′s available phosphorus and available potassium content compared with CF. Soil urease and alkaline phosphatase activities were significantly increased by 15.76%–19.51% (T1-T3 treatment) and 24.32%–34.25%, respectively, in organic fertilizers replacing chemical fertilizers treatments compared with CF. T1 and T3 treatments were more favorable for soil enzyme activities. The treatments were comprehensively evaluated using principal component analysis, and the scores were ranked as T1>CF>T2>T3>T4>T5>CK. Organic fertilizer replacement of chemical fertilizers can improve soil physical and chemical properties, soil enzyme activity, and the appropriate proportion of organic replacement of conventional fertilization, promoting the barley absorption and utilization of nutrients and improving yields. Organic fertilizer replacement of 20% of the treatment scored the highest for the recommended fertilization mode. [ABSTRACT FROM AUTHOR]

Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici has severely threatened sustainable greenhouse tomato production. However, the effects of nutrient enrichment due to excessive fertilization on Fusarium wilt remain unclear. This study aimed to investigate the relationships among soil nutrient enrichment, microbial community structure, and the occurrence of Fusarium wilt under greenhouse conditions. This study used chemical analysis and microbiological techniques to analyze rhizosphere soil samples from greenhouse tomato production areas with varying degrees of Fusarium wilt. The results showed that, as compared with the Health group, the rhizosphere soil of Disease group has a significant nutrient enrichment, which significantly influences bacterial diversity and structure. Particularly when soil NO3−–N content exceeds 170.43 mg kg−1, there was a significant reduction in the relative abundance of key biocontrol bacteria such as Bacillus and Lysinibacillus. This reduction indirectly contributes to an increase in Fusarium oxysporum abundance, subsequently elevating the likelihood of pathogen infection. Furthermore, the Disease group also exhibited a simplified co-occurrence network with a 22.37% reduction in competitive interactions between bacteria and fungi. These changes might collectively increase the risk of tomato Fusarium wilt infection. Meanwhile, the relative abundance of bacteria carrying antibiotic resistance genes significantly increased in the Disease group, which also reduced soil resistance. Together, the results presented here not only uncover the effect of long-term excessive fertilization on the occurrence of Fusarium wilt but also advance our understanding of the interactions among soil nutrient management and microbial communities in the tomato rhizosphere, which provides a scientific basis for formulating strategies to prevent soil-borne diseases in greenhouse tomatoes. [ABSTRACT FROM AUTHOR]

Late spring coldness (LSC) is the main limiting factor threatening wheat yield and quality stability. Optimal nutrient management is beneficial in mitigating the harms of LSC by improving wheat root physiology. This study proposed a nutrient management strategy that postponed the application of phosphorus (P) and potassium (K), effectively strengthening wheat's defense against LSC. This experiment used the winter cultivar "Yannong19" (YN 19) as plant material for two consecutive years (2021–2022 and 2022–2023). Two fertilizer treatments were used: traditional P and K fertilizers application (R1: base fertilizer: jointing fertilizer = 10:0) and postponed P and K fertilizers application (R2: base fertilizer: jointing fertilizer = 5:5); wheat plants at the anther connective formation stage shifted to temperature-controlled phytotrons for normal (T0, 11 °C/4 h) and low temperatures (T1, 4 °C/4 h; T2, −4 °C/4 h) as treatments of LSC. The results showed that under low temperature (LT) treatment, compared with R1, the R2 treatment increased the concentrations of osmotic adjustment substances (soluble sugars and soluble protein contents by 6.2–8.7% and 3.0–8.9%), enhanced activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase activities by 2.2–9.1%, 6.2–9.7% and 4.2–8.4%), balanced the hormone concentrations (increased IAA and GA3 contents by 2.8–17.5% and 10.4–14.1% and decreased ABA contents by 7.2–14.3%), and reduced the toxicity (malondialdehyde, hydrogen peroxide content and O2·− production rate by 5.7–12.4%, 17.7–22.8% and 19.1–19.1%) of the cellular membranes. Furthermore, the wheat root physiology in R2 significantly improved as the root surface area and dry weight increased by 5.0–6.6% and 4.7–6.6%, and P and K accumulation increased by 7.4–11.3% and 12.2–15.4% compared to R1, respectively. Overall, the postponed application of P and K fertilizers enhanced the physiological function of the root system, maintained root morphology, and promoted the accumulation of wheat nutrients under the stress of LSC. [ABSTRACT FROM AUTHOR]

Understanding spatio-temporal variability in the production of drift macroalgae is useful for monitoring and assessing the influence of local anthropogenic nutrient sources on coastal ecosystems. In this study we: (1) assessed how the drift macroalgal community composition and biomass have changed over a 22-year period in Port Phillip Bay (a large coastal embayment in Victoria, Australia); and (2) measured the amount of accumulated nitrogen in drift macroalgae and the contribution of anthropogenic nitrogen sources through isotopic analysis. The surveys revealed little overlap in species composition (<13%) and a significant decrease in standing stock biomass (from 631 to 49 g m-2) between surveys (1995/1996 and 2017/2018). This was associated with a high degree of turnover (β-diversity) at the genus level between surveys (mean – 0.53), resulting in distinct communities at all sites, particularly among red algal genera. In addition, the occurrence of ephemeral macroalgal blooms and a semi-perennial mat of the red macroalga Botryocladia sonderi at 10-15 m depth at locations close to nutrient sources indicate drift macroalgae are important nutrient accumulators in the bay. Isotopic analysis revealed a high contribution of anthropogenic-derived nitrogen (δ15N > 17‰ and ~ 3% N content) at depths and locations close to nutrient sources, particularly at times of the year when large wastewater discharges occur. Harvesting of drift macroalgae could be a cost-effective solution for offsetting nitrogen inputs from anthropogenic sources, but it will be important to first investigate whether harvesting results in negative impacts to associated fauna or nutrient cycling. [ABSTRACT FROM AUTHOR]

The growth and productivity of wild lingonberry (Vaccinium vitis-idaea L.) are closely influenced by various environmental factors, including soil composition, climate, light availability, and water levels. This review explores how these conditions and abiotic stress affect lingonberry populations in diverse habitats, from lowland regions to mountainous terrain. Light plays a critical role in flavonoid and anthocyanin synthesis, with solar radiation and photoperiod directly impacting fruit development. Additionally, altitudinal gradients influence the accumulation of polyphenols and vitamin C, while reducing plant height and pollinator activity. Soil types such as cambisols and podzols, often found in subalpine and alpine areas, are favorable for lingonberry growth. Climate factors, particularly winter temperatures and precipitation, significantly affect flowering success, with low temperatures and lack of snow cover negatively impacting fruit production. Forest type and density, including competing vegetation and nutrient availability, further determine the distribution and health of lingonberry populations. This review emphasizes the importance of favorable environmental conditions in promoting the vitality and yield of wild lingonberry, with potential implications for conservation efforts aimed at sustaining its productivity in natural habitats.

Integrated production systems have been an alternative for diversifying agricultural production, and therefore, it is necessary to study tropical forage grasses that can impact both straw production and soil organic matter, as well as benefit animal production. The objective of this work was to evaluate the productive characteristics and accumulation of nutrients in the biomass of grasses of the genus Panicum grown in the off‐season, in Cerrado biome soil as cover plants for use in integrated production systems. It evaluated different grasses of Panicum maximum: Aruana, Tamani, and Massai guinea grasses, distributed in a randomized block design with four replications of each grass. The productive characteristics, mineral accumulation, and carbon/nitrogen (C/N) ratio in the biomass of the cultivars were evaluated. No cultivar effect was observed for forage mass (3997.4 kg/ha DM). However, the largest (p = 0.0077) leaf blade masses were observed in the Massai and Tamani guinea grasses. On the contrary, the Aruana guinea grass exhibited the highest value (p = 0.0001) for stem mass, reflected in a higher (p = 0.0001) leaf/stalk ratio in the Massai and Tamani guinea grasses. No effect (p > 0.05) of the cultivar on micronutrients, magnesium, and phosphorus concentrations was observed. However, the Aruana guinea grass presented higher concentrations of calcium and sulfur; on the other hand, potassium values were higher in the Massai and Tamani guinea grasses. The Massai guinea grass exhibited a higher (p = 0.0214) C/N ratio, while the Aruana guinea grass recorded lower values, with no significant differences between these cultivars and Tamani guinea grass. The Tamani and Massai guinea grasses stand out as recommended choices for cultivation during the off‐season in Cerrado biome soils as cover crops in integrated production systems. [ABSTRACT FROM AUTHOR]

Abstract Understanding the efficacy of alternative phosphorus (P) sources in tropical soils is crucial for sustainable farming, addressing resource constraints, mitigating environmental impact, improving crop productivity, and optimizing soil-specific solutions. While the topic holds great importance, current literature falls short in providing thorough, region-specific studies on the effectiveness of alternative P sources in Brazilian tropical soils for maize cultivation. Our aim was to assess the agronomic efficiency of alternative P sources concerning maize crop (Zea mays L.) attributes, including height, shoot dry weight, stem diameter, and nutrient accumulation, across five Brazilian tropical soils. In greenhouse conditions, we carried out a randomized complete block design, investigating two factors (soil type and P sources), evaluating five tropical soils with varying clay contents and three alternative sources of P, as well as a commercial source and a control group. We evaluated maize crop attributes such as height, dry weight biomass, and nutrient accumulation, P availability and agronomic efficiency. Our results showed that, although triple superphosphate (TSP) exhibited greater values than alternative P sources (precipitated phosphorus 1, precipitated phosphorus 2 and reactive phosphate) for maize crop attributes (e.g., height, stem diameter, shoot dry weight and phosphorus, nitrogen, sulfur, calcium and magnesium accumulation). For instance, PP1 source increased nutrient accumulation for phosphorus (P), nitrogen (N), and sulfur (S) by 37.05% and 75.98% (P), 34.39% and 72.07% (N), and 41.94% and 72.69% (S) in comparison to PP2 and RP, respectively. Additionally, PP1 substantially increased P availability in soils with high clay contents 15 days after planting (DAP), showing increases of 61.90%, 99.04%, and 38.09% greater than PP2, RP, and TSP. For Ca and Mg accumulation, the highest values were found in the COxisol2 soil when PP2 was applied, Ca = 44.31% and 69.48%; and Mg = 46.23 and 75.79%, greater than PP1 and RP, respectively. Finally, the highest values for relative agronomic efficiency were observed in COxisol2 when PP1 was applied. The precipitated phosphate sources (PP1 and PP2) exhibited a similar behavior to that of the commercial source (TSP), suggesting their potential use to reduce reliance on TSP fertilization, especially in soils with low clay contents. This study emphasized strategies for soil P management, aimed at assisting farmers in enhancing maize crop productivity while simultaneously addressing the effectiveness of alternative P sources of reduced costs.

The rice production system in China is facing challenges, including declining soil fertility and a stagnant rice yield. This study aimed to test whether integrating the return of straw to fields with less power puddling could simultaneously enhance soil fertility and rice yields. Therefore, field experiments were conducted in Heilongjiang Province, a key rice-growing region in China, from 2017 to 2021, using three different planting methods: control group (CK), straw return (SR) and straw return integrated with less power puddling (SR + LP). The results showed that small soil aggregates (particle diameter < 0.25 mm) and soil bulk density were significantly decreased when straw return was integrated with less power puddling. These changes contributed to the preservation of soil structure. Simultaneously, this approach significantly increased soil ammonium nitrogen content from 9.9 to 10.9 mg kg−1, organic matter content from 35.0 to 36.2 g kg−1, available nitrogen content from 140.5 to 147.0 mg kg−1 and available potassium content from 128.6 to 136.8 mg kg−1 at mature stage on average. Consequently, the post-heading stored assimilates accumulation of rice was increased from 6.12 to 6.43 t ha−1, and the nitrogen, phosphorus and potassium accumulation of rice were increased by 7.85 kg ha−1, 1.13 kg ha−1 and 5.68 kg ha−1, respectively. These changes ultimately resulted in a higher 1000 g weight and filled grain rate, providing the foundation for higher yields (an increase from 9.31 t ha−1 to 9.55 t ha−1). Furthermore, this approach also increased the net income for farmers by USD 14 t ha−1. In summary, this study demonstrates that integrating straw return with less power puddling can enhance soil's nutrient supply and retention capacity. This enhancement may boost the absorption and transportation of nutrients, ultimately establishing the groundwork for higher yields and economic benefits by enhancing the 1000 g weight and filled grain rate. Future research should delve deeper into its applicability across different ecosystems and investigate the yield-increasing mechanisms. [ABSTRACT FROM AUTHOR]

Drained peatlands emit large amounts of greenhouse gases and cause downstream nutrient pollution. Rewetting aids in restoring carbon storage and sustaining unique biodiversity. However, rewetting for nature restoration is socio-economically not always feasible. Cultivation of Sphagnum biomass after rewetting allows agricultural production. In the short term, Sphagnum paludiculture is productive without fertilization but it remains unclear whether it sustains its functionality in the longer-term. We studied nutrient dynamics, organic matter build-up, and carbon and nutrient accumulation at a 16-ha Sphagnum paludiculture area in NW-Germany. Site preparation included topsoil removal and inoculation with Sphagnum and it was rewetted five and ten years ago and managed with mowing, irrigation, and ditch cleaning. The unfertilized sites were irrigated with (compared to bog conditions) nutrient-rich surface water and exposed to atmospheric nitrogen deposition of 21 kg N/ha/yr. Our data reveal that ten years of Sphagnum growth resulted in a new 30 cm thick organic layer, sequestering 2,600 kg carbon, 56 kg nitrogen, 3.2 kg phosphorus, and 9.0 kg potassium per ha/yr. Porewater nutrient concentrations were low and remained stable over time in the top layer, while ammonium concentrations decreased from 400–700 to 0–50 µmol/L in the peat profile over 10 years. Hydro-climatic fluctuations most likely caused the variation in ammonium in the top layer. We conclude that Sphagnum paludiculture enables rapid carbon and nutrient accumulation without active fertilization provided the biomass is not harvested, and provides perspective for bog restoration on agricultural peatlands. Large-scale application of Sphagnum paludiculture may mitigate environmental issues of unsustainable peatland-use. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of four types of slow-release fertilizers on the stoichiometric ratio of nitrogen, phosphorus, and potassium and biomass of Fraxinus malacophylla seedlings and to screen for the optimal fertilization amount for seedling growth. Four fertilization rates (0, 1, 2, and 4 kg m³) were employed as treatment for one-year-old F. malacophylla seedlings, with no fertilization (CK) as the control. Biomass, growth, and N, P, and K contents of each organ were measured, and the accumulation of N, P, and K was calculated. Curve fitting was performed to analyze the relationship between N, P, and K accumulation in various organs and stoichiometric ratio and biomass. The results showed that the best nutrient accumulation and biomass of F. malacophylla seedlings were obtained under the dosage of 1 kg m-3 slow-release fertilizer, and significantly higher than those of the control group. The biomass of each organ and the accumulation of N, P, and K was in this order as follows: leaf>root>stem, and the accumulation of nutrients in each organ and single plant was in this order; N>K>P. A highly significant positive correlation (P<0.01) was observed between the accumulation of N, P, and K in various organs and biomass of F. malacophylla seedlings. N: P and K: P negatively correlated with biomass, whereas N: K significantly positively correlated with biomass (P<0.05). The N: P values of all organs of F. malacophylla seedlings were <14; plant growth was limited by elemental N, N: K<2.10, and K P>3.40; and plant growth was not influenced by K. In summary, a dosage of 1 kg m-3 slow-release fertilizer is beneficial for the growth of F. malacophylla seedlings. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is essential for plants but very toxic at high rates. However, hyperaccumulators can tolerate high Mn concentrations in plant tissue, especially when properly fertilized with N. Tanzania guinea grass (Megathyrsus maximus Jacq.) has been indicated as metal tolerant and a good candidate for Mn phytoextraction due to its fast growth and high biomass. The objective was to evaluate the Mn hyperaccumulator potential of Tanzania guinea grass grown as affected by proportions of nitrate/ammonium (NO3−/NH4+). An experiment in a growth chamber with nutrient solution, combining NO3−/NH4+ proportions (100/0 and 70/30) and Mn rates (10, 500, 1500, and 3000 μmol L−1), was carried out. The highest Mn concentration was verified in plants grown with 100/0 NO3−/NH4+ and Mn at 3000 μmol L−1, reaching up to 5500 and 21,187 mg kg−1 in shoots and roots, respectively, an overall concentration of 13,345 mg kg−1. These numbers are typically seen in hyperaccumulators. At that combination, Mn accumulation in shoots was also the highest, reaching up to 76.2 mg per pot, a phytoextraction rate of 23.1%. Excess Mn increased both H2O2 concentration in roots and non-photochemical quenching and therefore decreased net photosynthesis, stomatal conductance, electron transport rate, and photochemical quenching. Nevertheless, proline concentration in roots affected by excess Mn was high and indicates its important role for mitigating stress since Mn rates did not even affect the dry biomass. Tanzania guinea grass is highly tolerant to excess Mn as much as a hyperaccumulator. However, to show all its potential, the grass needs to be supplied with N as NO3−. We indicate Tanzania guinea grass as a Mn hyperaccumulator plant. [ABSTRACT FROM AUTHOR]

Cropland acidification seriously restricts sustainable agricultural development. The main purpose of this study was to determine whether deeper tilling could alleviate topsoil acidification to improve the quality of arable land. A soil column incubation experiment simulating tillage depths (10 cm, 30 cm and 50 cm) and lime addition was conducted to determine their effects on soil acidification improvement. The changes in soil pH, exchangeable acidity, ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3−-N), available phosphorus (AP), and microbial phospholipid fatty acids (PLFA) were analyzed. Tillage depth, lime application, and their interaction all had significant impacts on soil pH. T50 (simulated tillage depth of 50 cm) and T50+Lime (simulated tillage depth of 50 cm plus lime) treatments significantly increased the topsoil pH from 5.41 to 6.35 and 7.12, respectively. T50 treatment significantly reduced the soil exchangeable acid content compared to the T10 treatment. The nutrient accumulation along soil column indicated that the T50 and T50+Lime treatments significantly increased NO3−-N and AP content in the >30–50 cm soil layer. Compared with T30, NO3−-N accumulation in the >30–50 cm soil layers of T50 and T50+Lime treatments was 6.62 and 7.93 times higher, respectively. The accumulation of AP in the >30–50 cm soil layers of the T50 and T50+Lime treatments was 1.33 and 1.54 times higher than in the T30 treatment, respectively. These findings imply tillage up to 50 cm without exogenous materials could be a potential measure to reduce topsoil acidification and increase nutrition availability of >30–50 cm soil layers. Tillage of up to 30 cm combined with lime application confers greater benefits, which would particularly impact crops with shallow root systems. Subsequent field experiments will be conducted to further investigate the efficacy of these strategies in enhancing crop yield.

Late spring coldness (LSC) is the main limiting factor threatening wheat yield and quality stability. Optimal nutrient management is beneficial in mitigating the harms of LSC by improving wheat root physiology. This study proposed a nutrient management strategy that postponed the application of phosphorus (P) and potassium (K), effectively strengthening wheat’s defense against LSC. This experiment used the winter cultivar “Yannong19” (YN 19) as plant material for two consecutive years (2021–2022 and 2022–2023). Two fertilizer treatments were used: traditional P and K fertilizers application (R1: base fertilizer: jointing fertilizer = 10:0) and postponed P and K fertilizers application (R2: base fertilizer: jointing fertilizer = 5:5); wheat plants at the anther connective formation stage shifted to temperature-controlled phytotrons for normal (T0, 11 °C/4 h) and low temperatures (T1, 4 °C/4 h; T2, −4 °C/4 h) as treatments of LSC. The results showed that under low temperature (LT) treatment, compared with R1, the R2 treatment increased the concentrations of osmotic adjustment substances (soluble sugars and soluble protein contents by 6.2–8.7% and 3.0–8.9%), enhanced activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase activities by 2.2–9.1%, 6.2–9.7% and 4.2–8.4%), balanced the hormone concentrations (increased IAA and GA3 contents by 2.8–17.5% and 10.4–14.1% and decreased ABA contents by 7.2–14.3%), and reduced the toxicity (malondialdehyde, hydrogen peroxide content and O2·− production rate by 5.7–12.4%, 17.7–22.8% and 19.1–19.1%) of the cellular membranes. Furthermore, the wheat root physiology in R2 significantly improved as the root surface area and dry weight increased by 5.0–6.6% and 4.7–6.6%, and P and K accumulation increased by 7.4–11.3% and 12.2–15.4% compared to R1, respectively. Overall, the postponed application of P and K fertilizers enhanced the physiological function of the root system, maintained root morphology, and promoted the accumulation of wheat nutrients under the stress of LSC.

【Objective】To explore the application effect and suitable substitution ratio of organic fertilizer substitute chemical fertilizer in potato production in the northern foothills of Yinshan Mountains in Inner Mongolia.【Methods】The experiment was conducted in Wuchuan County, Hohhot City, Inner Mongolia. Eight treatments were set up, including 100%M (100% organic fertilizer), 75%M (75% organic fertilizer + 25% chemical fertilizer), 50%M (50% organic fertilizer + 50% chemical fertilizer), 25%M (25% organic fertilizer + 75% chemical fertilizer), NPK (chemical fertilizer only, N 210 kg/hm², P2O5 120 kg/hm², K2O 180 kg/hm²), no nitrogen fertilizer (PK), no phosphorus fertilizer (NK), and no potassium fertilizer (NP) . The effects of different organic fertilizer substitution ratios on potato yield, nutrient accumulation, fertilizer utilization rate, and water use efficiency were analyzed.【Results】Under different organic fertilizer substitution ratios, yield, large tuber yield, small tuber yield, and number of tubers per plant of 25%M treatment were highest at 31 812, 18 250, 13.56 kg/hm², and 7.90, respectively. Increased by 3.14%, 2.22%, 4.39%, and 23.82% compared with NPK treatment. 25%M treatment had the highest increase of potato dry matter accumulation amount, and significantly higher (P<0.05) N accumulation amount compared with other treatments. Organic fertilizer increased potato fertilizer utilization rate, with 50%M treatment having the highest nitrogen fertilizer utilization rate at 43.94%. 25%M treatment had the highest phosphorus and potassium fertilizer utilization rate at 17.57%, 60.95% and highest agronomic efficiencies of nitrogen, phosphorus, and potassium fertilizer at 35.86%, 38.98%, and 25.00%, respectively. 25%M treatment had the highest water use efficiency at 125.81 kg/ (hm²·mm), significantly higher (P<0.05) than other treatments.【Conclusion】25%M (25% organic fertilizer + 75% chemical fertilizer) treatment increased potato yield, nutrient accumulation, and fertilizer utilization rate, improved water use efficiency, was the optimal fertilization method for potato production in the northern foothills of Yinshan Mountains in Inner Mongolia. [ABSTRACT FROM AUTHOR]

[Objective] This study investigated the effects of different fertilizer ratios on growth, leaf nutrients and chlorophyll content of young teak trees to provide references for determining appropriate fertilization program. [Method] Five fertilizer treatments of 0.25 kg/plant NPK compound fertilizer+0.25 kg/plant calcium-magnesium phosphate (Tl), 0.25 kg/plant calcium-magnesium phosphate+2.50 kg/plant rganic fertilizer (T2), 0.25 kg/plant NPK compound fertilizer + 0.25 kg/plant magnesium oxide+10.00 g/plant boron fertilizer (T3), 0.25 kg/plant NPK compound fertilizer (T4) and 0.25 kg/plant NPK compound fertilizer + 1.50 kg/plant calcium-magnesium-phosphorus fertilizer (T5) were configured with no fertilizer treatment as control (CK). The changes of growth, leaf nutrients and chlorophyll content of young teak trees in different treatments were analyzed, and the effects of different fertilization treatments were comprehensively evaluated by the affiliation function method. [Result] ➀ Compared with CK, different fertilization treatments increased the average increment of teak height, diameter at breast height and wood volume, among which T5 treatment was the best and increased average increment of teak height, diameter at breast height and wood volume by 44.81 %, 82.02% and 108.72%, respectively. ➁ Compared with CK, there was no significant change in total N, total K and exchangeable Ca content of teak leaves in different treatments, while total P and exchangeable Mg contents in leaves were significantly increased and leaf N/P was significantly decreased. ➂ Compared with CK, different treatments increased chlorophyll a, chlorophyll b and total chlorophyll contents of teak leaves while decreased chlorophyll a/b value, among which chlorophyll a and total chlorophyll contents of T5 were significant different from CK. ➃ The subordinate function method showed that the fertilizer effects of the five fertilizer ratios were in the descending order of T5> T3 >T2> T1 > T4. [Conclusion] All the test fertilization combinations could promote the growth and leaf nutrients of teak trees and the best was 0.25 kg/plant NPK compound fertilizer + 1.5 kg/plant calcium-magnesium-phosphorus fertilizer. [ABSTRACT FROM AUTHOR]

Little is known about C –N – P stoichiometries and content in teak (Tectona grandis) plantations in South China, which are mostly sited on hilly areas with lateritic soil, and the effect of slope position on the accumulation of these elements in trees and rhizosphere soils. Here we analyzed the C, N, P content and stoichiometry in leaves, fine roots and rhizosphere soils of trees on the upper and lower slopes of a 12-year-old teak plantation. The Kraft classification system of tree status was used to sample dominant, subdominant and mean trees at each slope position. The results showed that the C, N and P contents in leaves were higher than in fine roots and rhizosphere soils. The lowest C/N, C/P and N/P ratios were found in rhizosphere soils, and the C/N and C/P ratios in fine roots were higher than in leaves. Nutrient accumulation in leaves, fine roots and rhizosphere soils were significantly influenced by slope position and tree class with their interaction mainly showing a greater effect on rhizosphere soils. Leaf C content and C/N ratio, fine root C and P contents, and C/N and C/P ratios all increased distinctly with declining slope position. The contents of organic matter (SOM), ammonium (NH4+–N), nitrate-nitrogen (NO3−–N) and available potassium (AK) in rhizosphere soils were mainly enriched on upper slopes, but exchange calcium (ECa), available phosphorus (AP), and pH were relatively lower. Variations in the C, N and P stoichiometries in trees were mainly attributed to the differences in rhizosphere soil properties. N and P contents showed significant positive linear relationships between leaf and rhizosphere soil, and C content negative linear correlation among leaves, fine roots and rhizosphere soils. Chemical properties of rhizosphere soils, particularly C/N and NH4+–N, had significant effects on the leaf nutrients in trees on the upper slope. Correspondingly, rhizosphere soil properties mainly influenced fine root nutrients on the lower slope, and soil AK was the major influencing factor. Overall, these results offer new insights for the sustainability and management of teak plantations in hilly areas. [ABSTRACT FROM AUTHOR]

This study aimed to verify the effects of leaf application of zinc (Zn) on the growth, physiology, yield, and biofortification of snap beans. The experiment was carried out in a greenhouse, in a completely randomized design, with five doses of zinc (0, 100, 200, 300, and 400 mg L−1). The leaf application of zinc was carried out at the vegetative stage V3 (third leaves). Biometric, physiological, and yield evaluations occurred at stages R5 (flowering) and R8 (harvest). The chlorophyll of plants with zinc is 36% higher with the application of 400 mg L−1 in R8. Foliar fertilization reduced the transpiration around 41%; and it increased the temperature and photosynthetic rate at 5.2% and 16.2%, respectively. The zinc concentration increases up resulted in an increase of 85 and 942% of zinc accumulation in the snap bean plant at the R5 stage. The 100 mg L−1 dose increased crop yield by 8.4% compared to the control treatment. Higher doses can reduce productivity by up to 17% when 400 mg L−1 of Zn is applied. Foliar application of zinc is efficient in promoting an increase in the concentration and accumulation of Zn in the leaves in the stage R5, but at the harvest stage there is no influence of fertilization on the levels and accumulations of zinc in the plant. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted to elucidate the adaptive growth mechanism of maize under strip-till (ST) compared with conventional-till (CT). The biomass accumulation of ST plants was significantly lower than CT until V14 (14th leaf), but restored thereafter with one below-ear-node leaf reduced. At silking, the accumulation of nitrogen (N) was reduced by 8.3–10.7% compared to CT. During post-silking, vegetative-N remobilization was reduced by 20.4%, post-silking N uptake increased by 33.9% in ST compared to CT. Leaf senescence was delayed and more green leaf area at physiological maturity in ST. It is concluded that ST plants have the mechanism of 'Recovery Growth Adaptation' to get the similar yield as in CT plants: (1) facilitating growth rate at around V14 when the soil temperature was greatly improved to stabilize ear growth and grain number; (2) getting to silking the same time as in CT plants, so as to ensure the duration of grain filling; (3) increasing post-silking N uptake to fulfill the demand of grain development and reduce leaf N remobilization, so as to maintain leaf function and increase thousand-grain weight, which compensate for the loss of grain number per ear. [ABSTRACT FROM AUTHOR]

Irrational use of chemical fertilizers creates harmful effects on soil health and thus, led to a drop in crop productivity in the Indo-Gangetic Plains region (IGPR) of India. Organic nutrient sources such as Panchagavya and PGPR can be used to replace some proportion of chemical fertilizers to sustain productivity and soil health in the IGPR belt. This study was undertaken to determine the effect of integrated use of chemical fertilizers, organic manures and bio-fertilizers such as Panchagavya and PGPR on the productivity and economic feasibility of different maize cultivars. Results indicated that the J-1006 cultivar showed significantly higher fodder yield, nutrient use efficiencies and profitability than P-3396 and African Tall during both years. Though, nutrient content and accumulation were statistically at par with J-1006 and P-3396, but superior over African Tall. Among nutrient management, the maize fertilized with 75% RDF + PGPR +Panchagavya spray showed significantly higher fodder yield, nutrient content, accumulation, nutrient use efficiencies and net returns compared to control and 100% RDF. Overall, the growing of maize cv. J-1006 with the application of 75% RDF + PGPR + Panchagavya spray can be recommended to enhance fodder productivity, nutrient accumulation and profitability in the IGPR belt of India. [ABSTRACT FROM AUTHOR]

Solanum nigrum L. is an invasive weed in Xinjiang cotton fields, and an important factor affecting cotton quality and reducing cotton yield. Pendimethalin is the most commonly used pre-emergence herbicide on cotton. However, the status of S. nigrum resistance to pendimethalin and the physiological and biochemical mechanisms remain poorly understood. In this study, we investigated how S. nigrum regulates nutrient accumulation, protective enzyme activity, and metabolic enzyme activity in the body to resist injury following pendimethalin exposure. The results showed that the resistant BL‑1 population developed a higher level of resistance to pendimethalin than the sensitive SHZ‑8 population, with a resistance index of 26.20. After pendimethalin treatment, the activity of cytochrome P450 and glutathione S‑transferase enzymes was significantly higher in the resistant biotype than in the sensitive biotype, with peak values of 0.27 U L−1 and 0.22 U L−1 on day 25, respectively. The malondialdehyde and soluble sugar content, and superoxide dismutase activity of both sensitive and resistant biotypes first increased than decreased, but there were no significant differences in peroxidase activity or soluble protein content. The results show that S. nigrum developed a high level of resistance to pendimethalin in Xinjiang cotton fields, and differences in glutathione S‑transferase and cytochrome P450 enzymes associated with pendimethalin metabolism might be related to resistance. [ABSTRACT FROM AUTHOR]

Excessive nitrogen and insufficient calcium could significantly impact peanut yields. This study investigated the effects of nitrogen and calcium fertilizers on nutrient absorption, utilization, and yield; experiments were conducted using the peanut cultivar from Xianghua 2008 in a split-plot arrangement with two calcium fertilizer levels (Ca0: 0 and Ca1: 568 kg CaO ha−1) in the main plots and six nitrogen fertilizer gradients (N0: 0, N45.0: 45.0, N90.0: 90.0, N112.5: 112.5, N135.0: 135.0, and N157.5: 157.5 kg N ha−1) in subplots between 2015 and 2016 in Changsha, China. We examined the impact of different rates of calcium and nitrogen fertilizers on the net photosynthetic rate (Pn), agronomic traits, dry matter quality, yield and yield composition, nutrient accumulation, and distribution. The combined application of calcium and nitrogen fertilizers significantly affected the yield and yield components, Pn, main stem height, dry matter, and nutrient accumulation. Under the same calcium level, nitrogen application significantly increased the main stem height and Pn and promoted the accumulation of dry matter and nutrients in the plant, particularly in the kernel. Under the same nitrogen treatment, calcium significantly increased Pn and promoted the accumulation of dry matter, calcium, and magnesium. The pod yield increased gradually with an increasing nitrogen application rate (0–112.5 kg ha−1) and peaked at N112.5, increasing by 52.3–138.0% compared with N0. However, excessive nitrogen application (N > 112.5 kg ha−1) decreased the pod yield. Under different nitrogen fertilizer levels, calcium application increased pod yields by 11.5–29.6% by promoting Pn, nutrient uptake, accumulation in the individual plant, and nutrient accumulation in the kernel. Therefore, this study suggested that adjusting the calcium (568 kg ha−1) and nitrogen (112.5 kg ha−1) fertilizer rates significantly improved peanut growth and productivity by enhancing photosynthetic efficiency and nutrient accumulation in calcium-deficient acidic red soil. [ABSTRACT FROM AUTHOR]

It was assumed that the production of alfalfa in soils naturally poor in available nutrients, such as potassium (K) and calcium (Ca), depends on the use of fertilizers. This hypothesis was validated in an experiment with an alfalfa–grass mixture carried out in 2012, 2013 and 2014 on soil formed from loamy sand that had a low content of available Ca and K. The two-factor experiment consisted of two levels of applied gypsum as a source of Ca (0, 500 kg ha−1) and five levels of PK fertilizers (absolute control, P60K0, P60K30, P60K60 and P60K120). The total yield of the sward was determined by the main seasons of alfalfa–grass sward use. Gypsum application increased the yield by 1.0 t ha−1. The highest yield of 14.9 t ha−1 was obtained on the plot fertilized with P60K120. Based on the nutrient content in the sward, it was shown that the main yield predictor was the content of K in the first cut of sward use. The reliable yield predictors, based on the total accumulation of nutrients in the sward, turned out to be K, Mg and Fe. The nutritional quality of the alfalfa–grass fodder, based on the K/Ca + Mg ratio, depended mainly on the season of the sward use, which was substantially deteriorated by the K fertilizer. Gypsum did not control this process. The productivity of the nutrients taken up by the sward depended on the accumulated K. Its yield-forming effect was significantly limited by manganese deficiency. The use of gypsum positively affected the uptake of micronutrients, consequently increasing their unit productivity, especially of manganese. Optimization of the production of alfalfa–grass mixtures in soils poor in basic nutrients requires micronutrients to be taken into account. Their uptake by plants can be limited by high doses of basic fertilizers. [ABSTRACT FROM AUTHOR]

Biochar is frequently utilized as a helpful amendment to sustain agricultural productivity. However, it remains uncertain whether biochar can effectively replace chemical fertilizers, especially in karst regions. To investigate the effects of co-applying biochar and chemical fertilizer on the biological characteristics and fertilizer uptake of pod peppers, as well as to determine the optimal ratio of biochar to chemical fertilizers, a two-year field experiment was conducted in southwest China. The results showed that, compared to the locally typical chemical fertilizer treatment (CF), the combined application of biochar and chemical fertilizer significantly increased the yield of both fresh and dry pod pepper. Chemical fertilizer reduction and biochar application also ameliorated fruit quality, increased nutrient accumulation, and improved fertilizer utilization efficiency. What is more, although the employment of biochar made production costs higher, the reduction in chemical fertilizers and the increase in yield improved economic efficiency, especially in the CF70B treatment (70%CF + biochar). In conclusion, moderate amounts of biochar instead of chemical fertilizers may be a valid nutrient management strategy for pod pepper in the karst mountain areas, which is beneficial for maintaining yield stability, improving quality, and increasing net income. [ABSTRACT FROM AUTHOR]

In the rice–rapeseed rotation system, straw incorporation plays an important role in achieving the rational utilization of resources and maintaining crop production. However, in the study of rice–rapeseed rotation, there was no study on the effect of straw and nitrogen (N) fertilizer in the rice season on the dry matter accumulation (DMA) and nutrient accumulation of subsequent rapeseed. So, this study relied on the localization experiment of rice–rapeseed rotation and annual straw incorporation (full straw returning to the field, SR; the control is full straw removal from the field, CK) with different N fertilizer application rates (N1: 0 kg ha−1, N2: 75 kg ha−1, N3: 150 kg ha−1, and N4: 225 kg ha−1) in the rice season. Based on the fourth year of experiment implementation, the effects of annual straw incorporation combined with the N fertilizer application rate in the rice season on the leaf area index (LAI), photosynthetic potential (PP), DMA and its distribution proportion and rate, and nutrient uptake and its allocation proportion in rapeseed were discussed. At the bolting stage (BS), initial flowering stage (IFS), terminal flowering stage (TFS), and mature stage (MS), the DMA of rapeseed in SR was significantly higher than that in CK by 69.90, 64.27, 62.90, and 41.27%, respectively. The accumulation of N, phosphorus (P), and potassium (K) in SR was significantly higher than that in CK at the BS, IFS, TFS, and MS. Straw treatment had a significant impact on the apparent surplus of N, P, and K in the rice, rapeseed, and annual seasons, while the application of N fertilizer in the rice season had a significant or extremely significant impact on the apparent surplus (AS) of N in the rice, rapeseed, and annual seasons, indicating that fertilization of previous crops had a certain aftereffect. Therefore, straw incorporation is a sustainable farmland management measure. [ABSTRACT FROM AUTHOR]

Excessive chemical fertilizer application in greenhouse vegetable cultivation results in environmental risks and residual nutrients in the soil. Conventional plot experiments conducted in one field cannot recommend fertilizer reduction to farmers when the residual nutrient levels were various among different fields. In this study, nine plot experiments were simultaneously conducted in nine greenhouse fields where the soils could reflect different residual levels of nutrient, with two application rates (100 and 0%) for each nitrogen, phosphorus, and potassium fertilizer. The results showed that fertilizer reduction did not decrease vegetable yield when soil nitrate, Olsen–phosphorus, and exchangeable potassium were ≥173.3, 45.8, and 93.1 mg kg−1, respectively. However, no N treatment decreased vegetable yields in fields 1–3 because the inadequately residual nitrate (≤103.9 mg kg−1) in these fields led to low nitrate absorbed from sources other than chemical fertilizer, high recovery efficiencies of N, and high productivity of N absorbed from chemical fertilizer. Residual nitrate that soil EC could reflect was the limiting factor of yield under fertilizer reduction. This study indicated that reducing fertilizer in greenhouse vegetable cultivation should be based on the residual level of nutrients in the soil, which is meaningful in agricultural sustainability and environmental safety. [ABSTRACT FROM AUTHOR]

The increase in water demand in regions with limited good-quality water resources makes it necessary to study the effect of low-quality water on plant metabolism. Therefore, the objective of this study was to evaluate the effect of water and salt stress on the levels of mineral elements and accumulation of toxic elements Na+ and Cl− in the leaves and their consequences on the production variables of the sorghum cultivar IPA SF-15. The design adopted was randomized blocks in a factorial scheme (4 × 4), with four salt concentrations (1.5; 3.0; 4.5, and 6.0 dS m−1) and four irrigation depths (51.3; 70.6; 90.0, and 118.4% of crop evapotranspiration ETc) in three repetitions. To obtain nutrient, sodium, and chlorine contents in the leaf, we collected the diagnosis leaf from six plants per plot. For production data, we performed two harvests at 76 and 95 days after planting (silage point and for sucrose extraction). We evaluated the dry mass, fresh mass yield, and total dry mass for the two cutting periods and applied the F-test at the 5% significance level. There was an effect of water stress but not saline, making it possible to use saline water for sorghum irrigation. As for the toxicity of ions, the plant showed tolerance behavior to Na+ and Cl− ions. The grain filling phase was more sensitive than the final phase of the crop cycle. [ABSTRACT FROM AUTHOR]

The Gulf of Elat/Aqaba exhibits high inter‐annual variability in mixed layer depth. Observations from the northern Gulf show differences of hundreds of meters in winter mixing depth, which ranges between 300 m in years with shallow mixing and up to 700 m in years with deep mixing. Deep mixing events can occur in two consecutive years or after four consecutive years of shallow mixing. The mixing depth has an effect on the concentration of nutrients and chlorophyll (and other tracers) in the surface and deep water. Using a 3D coupled physical‐ecological model, we studied the effect of shallow versus deep mixing on the processes controlling the phytoplankton bloom and on nutrient accumulation in the deep water. We found that years with deep mixing are characterized by larger spatial variability in surface and integrated chlorophyll concentration during the mixing season. We found that horizontal advection is a dominant contributor for integrated phytoplankton concentration in years with deep mixing in the northern Gulf. Even when mixing was deep and nutrient limitation decreased, light limitation on phytoplankton integrated growth was enhanced in the north compared with the south. In addition, we showed that the nutrient accumulation in the deep water after a year with deep mixing in the northern Gulf was initially affected mostly by physical processes (such as advection and vertical mixing), and less from ecological regeneration, and switched to be dominated by ecological processes alone during the third year after mixing. Plain Language Summary: Primary production by phytoplankton is the base of the marine ecological system and is an important mechanism for the sequestration of carbon from the atmosphere into the ocean. In this work, we studied the effect of varying mixed layer depths on the mechanisms for phytoplankton bloom initiation, a phenomenon of increased phytoplankton concentration. We studied the Gulf of Elat/Aqaba, a relatively small basin, which exhibits years of shallow and very deep mixing. We found that deep mixing caused increased spatial variability in phytoplankton concentration between the northern and southern Gulf, both in the surface water and in the integrated column. Increase in mixed layer depth caused an increase in the effect of horizontal advection on the phytoplankton concentration in the whole water column in the northern Gulf. In addition, it caused light limitation on growth to increase in the northern Gulf, even though nutrients were more abundant after deep mixing. Finally, we showed that nutrient accumulation in the deep water of the northern Gulf after deep mixing, which decreased their concentration in depth, was initially mostly due to physical processes of mixing and advection, but in the third year after mixing was dominated by ecological regeneration. Key Points: Horizontal advection effect on northern Gulf integrated phytoplankton concentration increased with mixed layer deepeningDespite increased nutrient input by enhanced mixing, light remained the main limitation on northern Gulf's integrated phytoplankton growthNutrient accumulation in the deep water was driven mostly by physical processes immediately after mixing [ABSTRACT FROM AUTHOR]

With increasing anthropogenic activities, rivers and streams have become vulnerable to pollution; therefore, monitoring potential contaminants and the pollution status of surface sediments is essential. This study analyzed the concentrations of organic matter, metals, and metalloids; indices for organic, metal, and metalloid pollution; and ecological risk in river and stream sediments at 82 stations across Korea in 2017, 2018, and 2020. We performed bootstrapped analysis of variance, principal component analysis, and cluster analysis and used a structural equation model (SEM) to investigate spatiotemporal changes in the pollution status, main pollutant chemicals, and the exogenous factors affecting pollution status. The results suggest no significant differences in any of the twelve single chemical parameters and three pollution indices across the surveyed years. Metals, metalloids (Cu, Zn, Pb, and Hg), and organic matter with nutrients were identified as the main pollutants. The SEM demonstrated the significant influence of pollution sources—water used for industrial purposes, landfill wastewater discharge, and industrial wastewater discharge—on organic pollution, metal and metalloid pollution load, and environmental toxicity. This study identified consistently polluted areas, proposed additional management policies and stricter regulations on major point pollution sources rather than on broader land-use types, and suggested the combined consideration of metal toxicity risk with nutrient accumulation for future risk assessments. [ABSTRACT FROM AUTHOR]

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The rice production system in China is facing challenges, including declining soil fertility and a stagnant rice yield. This study aimed to test whether integrating the return of straw to fields with less power puddling could simultaneously enhance soil fertility and rice yields. Therefore, field experiments were conducted in Heilongjiang Province, a key rice-growing region in China, from 2017 to 2021, using three different planting methods: control group (CK), straw return (SR) and straw return integrated with less power puddling (SR + LP). The results showed that small soil aggregates (particle diameter < 0.25 mm) and soil bulk density were significantly decreased when straw return was integrated with less power puddling. These changes contributed to the preservation of soil structure. Simultaneously, this approach significantly increased soil ammonium nitrogen content from 9.9 to 10.9 mg kg−1, organic matter content from 35.0 to 36.2 g kg−1, available nitrogen content from 140.5 to 147.0 mg kg−1 and available potassium content from 128.6 to 136.8 mg kg−1 at mature stage on average. Consequently, the post-heading stored assimilates accumulation of rice was increased from 6.12 to 6.43 t ha−1, and the nitrogen, phosphorus and potassium accumulation of rice were increased by 7.85 kg ha−1, 1.13 kg ha−1 and 5.68 kg ha−1, respectively. These changes ultimately resulted in a higher 1000 g weight and filled grain rate, providing the foundation for higher yields (an increase from 9.31 t ha−1 to 9.55 t ha−1). Furthermore, this approach also increased the net income for farmers by USD 14 t ha−1. In summary, this study demonstrates that integrating straw return with less power puddling can enhance soil’s nutrient supply and retention capacity. This enhancement may boost the absorption and transportation of nutrients, ultimately establishing the groundwork for higher yields and economic benefits by enhancing the 1000 g weight and filled grain rate. Future research should delve deeper into its applicability across different ecosystems and investigate the yield-increasing mechanisms.

IntroductionSoybean breeding in southwestern China has vastly improved soybean yields with the increasing demand for nutrients such as phosphorus (P) and nitrogen (N). This study aimed to assess the impact of soybean breeding on P and N utilization efficiencies.MethodsField experiments with split-plot experimental designs were conducted at two locations [Dafang (DF) and Shiqian (SQ)] in the 2019 growing season to determine the agronomic efficiency of P fertilizer (AEp), P and N utilization efficiencies, and P and N accumulation and partitioning in different soybean organs under 0 (P0) and 35 (P35) kg ha−1 P supply.ResultsThe results showed that soybean breeding targeting high seed yield also improved AEp (p < 0.05) and P (p < 0.05) and N utilization efficiencies (p < 0.05), with the improvement in AEp associated with the high yield response to P supply. P and N accumulation significantly increased in pods (p < 0.05) and leaves (p < 0.05) but not in stems or roots with year of release, while P and N concentrations did not change in any organ with year of release. In addition, only pod dry weight significantly increased (p < 0.01) with year of release, and P and N partitioning increased to pods (p < 0.05) but decreased to stems (p < 0.05) with year of release. Correlation and PCA analyses revealed P and N utilization efficiencies positively correlated with P and N partitioning to pods but negatively correlated with P and N partitioning to stems. While P supply increased P and N accumulation, it reduced P utilization efficiency.DiscussionWe conclude that (1) soybean breeding improved AEp and P and N utilization efficiencies; (2) the increased P and N partitioning to pods but decreased partitioning to stems contributed to the high P and N utilization efficiencies in new soybean cultivars, reducing the demand for N and P; (3) P supply increased nutrient accumulation but reduced P utilization efficiency. These results highlight the significance of appropriate resource allocation among organs and efficient P management for enhancing nutrient utilization and reducing fertilizer requirements.

In order to investigate the growth and nutrient accumulation characteristics of Cinnamomum camphora (L.) Presl coppice cutting seedlings, and provide better guidance for fertilizer application. The plant height, biomass and nutrient content of Cinnamomum camphora (L.) Presl coppice cutting seedlings under the current customary planting pattern in Jiangxi area were dynamically monitored. This study dynamically monitored the plant height, biomass and nutrient content of Cinnamomum camphora coppice cutting seedlings under the current customary planting pattern in Jiangxi area. The results show as follows. The plant height, biomass and C, N, P and K accumulation of Cinnamomum camphora (L.) Presl coppice cutting seedlings can fit with the Logistic equation. The determination coefficient (R²) of each index is between 0. 962 and 0. 994 in the fitting equation, and the growth rate all change with the mono peak rule of “slow-fast-slow”. The rapid growth period of plant height and biomass start from May 16th to August 17th and From June 26th to September 14th, respectively. The duration of rapid growth for both indexes is 93. 7 d and 79. 8 d, correspondingly. The maximum growth rate of plant height is 0.26 cm/d occurred on July 2nd, and the maximum growth rate of biomass is 0. 24 g / (d·m²) occurred on August 5th. The accumulation patterns of C, N, P, and K are not entirely consistent with biomass. The duration of rapid accumulation of C and P is roughly the same as that of biomass, with 81. 1 d and 77. 4 d, respectively. The N accumulation start late (June 30th) and end early ( September 3rd), and the K accumulation start the earliest ( June 26th) and end the earliest (August 22nd). The rapid accumulation duration of N, K are 64. 7 d and 57. 1 d, with 15. 1 d and 22. 7 d lower than the biomass respectively. In conclusion, the results show that the increase of plant height, biomass and nutrient accumulation of Cinnamomum camphora (L.) Presl coppice cutting seedlings change over time under the current customary planting pattern. Biomass growth obviously lags behind the plant height, and the end and duration time of N and K accumulation are smaller than biomass. The results indicate that And there is an obvious shortage of N and K in the late growth stage of Cinnamomum camphora (L.) Presl coppice cutting seedlings under the current customary planting pattern. In order to ensure the nutrients that Cinnamomum camphora (L.) Presl cutting seedlings need for its normal growth, appropriate amount of N and K fertilizers should be applied in the later stage according to its growth and nutrient accumulation characteristics. [ABSTRACT FROM AUTHOR]

Fertilization programs in lilium are suggested to start after shoot emergence or when the flower buds become visible because the nutrients stored in the bulb are adequate to meet plant demands at the transplant time. Defining plant nutrient uptake is essential to determine the periods of high demand and the amounts at which they should be provided. The objective of this study was to model the nutrients accumulated in Oriental lilium to provide insight into the design of environmentally sound fertilization programs. The most demanded macronutrient was K (1272.8 mg/plant), followed by N (719.1 mg/plant) and Ca (119.7 mg/plant), while Zn (140.7 mg/plant) and Fe (137.7 mg/plant) were the most demanded micronutrients. At the end of the season, most of the Fe (78.0%), P (55.0%) and N (54.3%) originated from the bulb, whereas most of the Ca (86.5%), Mn (84.8%) and Mg (62.9%) were uptaken by roots. During the first 15 days after transplant, 35.1% of the N in the shoot was absorbed from the substrate, as well as 91.0% Mg, 68.6% S, 49.6% K and 13.0% P, suggesting that fertilization for lilium should start at the transplant time. The results suggest that Ca, Fe, Zn and Cu were remobilized from the bulb. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We aimed to explain and compare Ca, Mg, and S uptake dynamics by two common bean cultivars with contrasting growth habits as a function of water deficit severity in two years to generate more specific information for their fertilization management. A field study was set up using the cultivars IAC Imperador, with a determinate growth habit and early cycle, and IPR Campos Gerais, with an indeterminate growth habit and intermediate cycle. These cultivars were maintained under three irrigation levels, that is, severe (54% ETc), moderate (77% ETc), and no water deficit (100% ETc). The absorption order was Ca > Mg > S, regardless of the treatment. For the IAC Imperador, the Ca uptake ranged from 72 to 127 kg ha−1, Mg from 17.2 to 39.1 kg ha−1 and S from 7.9 to 16.5 kg ha−1, while for the IPR Campos Gerais it ranged from 92 to 156 kg ha−1, 21.0 to 36.5 kg ha−1 and 14.6 to 33.7 kg ha−1, respectively. Overall, severe water deficit reduced Ca, Mg, and S absorption by more than 25%. The IPR Campos Gerais presents, on average, 64% higher S accumulation, while the highest Ca and Mg accumulation order depends on the year. Compared to the IAC Imperador, this cultivar showed a later S absorption peak (up to +23 days), and higher interannual variability in the growth and nutrient absorption due to its indeterminate growth habit. These differences evidence the importance of specific fertilizer management practices for Ca, Mg and S in common bean, assisting in optimizing nutrient use. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)