Manure Treatment Research Articles

Developing Guidelines for Azolla microphylla Production as Compost for Sustainable Agriculture

Azolla is a substitute compost that has the potential to enhance nutrient cycling in agricultural systems for sustainable development. In this study, four experiments were conducted to compare the Department of Agriculture (DOA, Thailand) ‘s methodology for determining the suitable type and rate of animal manure and the optimal light intensity for the growth and yield of Azolla (Azolla microphylla). The results revealed that applying 100% pig manure gave the highest yield of Azolla compared to the other manures. However, there was no discernible (p > 0.05) difference in yield across the various doses (20.16, 30.16, and 40.16 gN m−2) of pig manure treatments, for which the minimal pig manure dosage of 20.16 gN m−2 was chosen. For further experimentation in the optimal light intensity, the 40% shading gave the highest yield of Azolla compared to no shading or 20 and 60% shading (p ≤ 0.01). When compared with the DOA Thailand methodology (1.27 kg m−2 of cow manure and covered with a size 32 mesh net), the findings indicated that the modified method (20.16 gN m−2 of pig manure + 40% shading) gave a 16% greater Azolla yield than that under the DOA Thailand methodology. The current finding method can produce a monthly fresh biomass of A. microphylla of 40.7 t ha−1 year−1 with higher contents of total N (4.92%) and lower C:N ratio (≤10:1) that could release minerals relatively rapidly. Its use can be encouraged by farmers to produce their own ecofriendly biofertilizer or soil amendment for sustainable agriculture.

The effect of organic manure on the production of jute (Corchorus olitorius)

Field experiments to investigate the effect of different sources of organic manure (Swine manure (SM), Poultry manure (PM), Cattle manure (CM), Rabbit urine manure (RUM)) on production of Jute (Corchorus olitorius) was carried out. The experimental site was cleared and cultivated (tilled and fertilized). Treatments were laid out before planting at once, there was no re-application of treatment. Data were collected on growth and yield parameters (Foliage, Plant height and Plant fresh weight). There was a significant difference in the foliage of Corchorus olitorius treated with SM, PM, CM, and RUM when compared with the control group. The foliage of Corchorus olitorius with PM treatment is significantly higher (P<0.05) compared with other organic manure treatment except for CM. Significant increase (P<0.05) in the height of Corchorus olitorius was obvious in all the treatment group when compared with control. There is no significant difference (P>0.05) in the height of jute across the organic manure treatment groups (SM, PM and RUM) but there is a significant increase in the plant height of PM when compared CM. SM, PM and RUM significantly increase the fresh weight of the plant when compared with the control and CM. There was a numerical increase in the plant fresh weight of PM when compared to other treatment groups. From this experimental study, PM consistently increased the number of leaves, the fresh plant weight and plant height significantly and it is recommended for Corchorus olitorius production.

Optimization of Amaranthus production under irrigation and poultry manure application using grey relational analysis

This study was carried out to optimize Amaranthus production under varying irrigation levels and poultry manure applications using Grey Relational Analysis. The experimental design was split-plot, where irrigation treatment was the main plot, while poultry manure was the subplot treatment. The irrigation levels are FIT50, FIT75, FIT100 and FIT135 which correspond to 50% Full irrigation, 75% full irrigation, 100% full irrigation and 135% full irrigation treatments, in combination with the poultry manure application rates M0t/ha, M5t/ha, M10t/ha and M20t/ha. Sixteen experimental treatments were arranged in a 4 x 4 factorial experimental design and replicated 3 times. Sprinkler irrigation system was adopted for the study. Results showed that there was corresponding increase in the response of Amaranthus growth characteristics and yield to the combination of irrigation and poultry manure treatments. The Crop Water-use efficiency initially showed a linear corresponding increase to an average value of 473kg/ha/mm but later exhibits a diminishing return beyond FIT100 irrigation. While production cost showed continual increase to average value of $377/ha as the inputs treatment level also increased to FIT135 irrigation combined with the poultry manure M20t/ha. Grey Relational Grades (GRG) calculated were 0.854, 0.790, 0.787, 0.765, 0.740, 0.629, 0.621, 0.620, 0.546, 0.543, 0.515, 0.475, 0.458, 0.443, 0.417 and 0.403 respectively. Amaranthus cultivated under FIT100_M20t/ha treatment matched with the highest GRG value 0.854, making FIT100_M20t/ha treatment the optimum. Analysis of variance for the GRG showed that irrigation and poultry manure are highly significant input variables for Amaranthus production. The findings from this study guide farmers on the optimal combination of water and organic fertilizer to maximize Amaranthus yield and minimize resource waste, thereby enhancing sustainability in crop production.

Synergistic organic manure treatment with Al/Fe/Ca-based fluoride-fixing agents promote soil formation and utilization of phosphate flotation tailings

Soil utilization of phosphate ore flotation tailings (PTs) was achieved using F-fixing agents combined with organic manure treatment to address issues related to inefficient stabilization of P-F, heavy metal solidification/stabilization, poor physicochemical properties, and ecological disruption. The formulation for PTs soil utilization included 1.75 % polyaluminum sulfate (PAS), 1.75 % FeSO4, and 0.25 % CaO, with PTs content at ≥86.75 %. This approach enhanced water retention and improved nutrient and biochemical conditions. Various nutrient indexes met general planting soil requirements: organic matter 24.93 g/kg, available K 252.26 mg/kg, available Ca 2048.67 mg/kg, available Mg 246.13 mg/kg, and ammonia-nitrogen 42.47 mg/kg. The water-soluble P content of PTs-based soil decreased to 6.96 mg/kg, while available P increased to 677.99 mg/kg. Mn leaching toxicity was less than 0.016 mg/L, with a stabilization efficiency of 96.86 %. Water-soluble F in PTs-based soil was reduced to 11.133 mg/kg. This study maximized phosphorus resource utilization and prevented the migration of water-soluble P, F, and Mn to the surrounding environment. Potting experiments showed PTs-based soil was more effective than red soil and PTs-based raw materials in cabbage plantation, achieving a maximum seedling emergence rate of 98.33 %. Microbial diversity increased, and community structure improved in 40-day soil formation experiments, with PTs-based soils developing microbial communities involved in carbon and nitrogen cycling, enhancing resistance to external environmental disturbances, and promoting ecological utilization. These findings offer practical insights into the ecological utilization of large quantities of PTs and present a cost-effective approach for producing planting soils or ecological mulches from similar solid wastes.

Optimizing Lemon Balm (Melissa Officinalis L.) Cultivation: Effects of Different Manures on Plant Growth and Essential Oil Production During Consecutive Harvests

This study examined the impact of organic manures from different sources (poultry, sheep, and cattle) on lemon balm (Melissa officinalis L., Lamiaceae) during different harvests. Manure application increased the photosynthetic pigments levels (chlorophyll-a, 9–41%; chlorophyll-b, 24–60%), biomass (41–60%), and essential oil yield (60–71%). Sheep manure treatment exhibited the highest antioxidant capacity among all the manures tested. Through GC-MS and GC-FID analysis, 10 chemical constituents were identified in the essential oil, accounting together for 91–95% of the total composition. The primary chemical component was geranial (39–46%), followed by neral (28–35%), (E)-caryophyllene (4.7–11%), geranyl acetate (2.7–5.9%), and caryophyllene oxide (1.7–4.8%). The utilization of livestock manures significantly improved the quality of the essential oil in terms of neral and geranial percentages compared to the control. Notably, during mid-August and early October, there was a substantial rise in these valuable compounds. However, a decrease in geranyl acetate and oxygenated monoterpenes resulted in a decline of the antioxidant capacity to 3%. Consequently, it is recommended to utilize essential oils from the second and third harvests for industrial purposes. Overall, the use of livestock manures, especially sheep manure, as a nutrient source for lemon balm cultivation, proves to be a viable approach for producing high-quality essential oils.

Growth Rate and Nutrient Uptake of Stevia rebaudiana Bertoni as Influenced by Organic Manures in Laterite Soils of Kerala, India

A field experiment was conducted to understand the effect of organic manures on the crop growth rate (CGR), relative growth rate (RGR), and nutrient uptake of stevia (Stevia rebaudiana Bertoni) from April to August of 2022 and 2023 at the Agronomy farm, Department of Agronomy, College of Agriculture, Vellanikkara, Thrissur. The experiment was laid out in randomized block design (RBD) with 7 treatments replicated thrice which consisted of different levels of organic manures viz., three levels of farmyard manure (FYM@ 5, 10, 15 t ha­-1), three levels of vermicompost (VC@ 2.5, 5, 7.5 kg ha-1) and a control. The organic manure treatments significantly affected crop growth rate (CGR) and relative growth rate (RGR) in all the growth periods. The two-year pooled mean of CGR of stevia was significantly superior in FYM@15 t ha-1 over control in all the three growth periods i.e., at 0-30 DAP, 30-45 DAP and 45 DAP to harvest. Whereas, the two-year mean of RGR of stevia was found statistically higher in FYM@15 t ha-1 over control in the first two growth periods only. The organic manure treatments had a significant influence on the plant nutrient (NPK) uptake as well in both the years. The two-year pooled mean data regarding plant uptake of nitrogen and phosphorous was found significantly higher in FYM@15 t ha-1 over control whereas statistically higher pooled mean potassium uptake by stevia was found in VC@7.5 kg ha-1 over control. Overall, the higher levels of organic manure, especially FYM, significantly improve growth and nutrient uptake in stevia.

Characterization of phosphorus balances in corn silage fields from eight New York dairies

AbstractOptimizing phosphorus (P) application in corn (Zea mays L.) silage production systems to align with crop P requirements while sustaining soil test P (STP) levels can help mitigate environmental risks and enhance farm profitability. The objectives of this study were to characterize P balances of corn silage fields in New York, their drivers, relationships between P balances and field STP and nitrogen (N) balances, as well as the impact of manure application practices on balances. Field‐level balances (supply–uptake) for P and N were derived for 994 field observations across eight dairy farms and 5 years. On average, P balances were low (11 kg P ha−1) with a wide range across farm averages (−11 to 30 kg P ha−1). Across farms, P was applied at higher rates to fields with adequate STP than to lower STP fields, indicating potential opportunities for reallocation of P within farms. Phosphorus balances were positively related to N balances. Manure nutrient utilization indicated that N‐based applications would lead to large positive P balances in all farms. Phosphorus‐based manure applications could cover on average 51% of corn N requirements under current farm manure application practices. This could be increased up to 85% when maximizing the utilization of manure inorganic N. Management alternatives to prevent excessive P balances include improving diet formulation to reduce P excretion, reducing animal density, exporting manure, implementing manure treatment technologies that conserve N and/or remove P, combining appropriate rates of manure and fertilizer, and maximizing manure inorganic N utilization in field applications.

Differences in Nitrogen Sources and Contributions in Shallow Groundwater in Plateau Lake Area with Different Climate Types

Clarifying the concentration, major sources, and contribution differences of nitrogen in shallow groundwater in plateau lake areas with different climate types can provide a novel direction for the control of nitrate （NO3-） pollution in regional groundwater. Taking the shallow groundwater around Erhai Lake in the subtropical monsoon climate zone and Chenghai Lake in the dry-hot valley area of the Jinsha River as the research objects, using hydrochemical indexes and multi-isotope techniques （δ15N-NO3-, δ18O-NO3-, δ18O-H2O, and δ2H-H2O） combined with the stable isotope （SIAR） model； the differences in nitrogen concentration in shallow groundwater around Erhai Lake and Chenghai Lake were analyzed, the sources of NO3- were identified, and the contribution rates of each pollution source were calculated. The results showed that water quality of more than 33% and 5% of shallow groundwater sampling points around Erhai Lake and Chenghai Lake was worse than the groundwater Class Ⅲ quality requirements （GB/T 14848） of 20 mg·L-1 for nitrate nitrogen （NO3--N）, respectively. The δ18O-H2O and δ2H-H2O in shallow groundwater around Erhai Lake and Chenghai Lake were parallel to the global and Chinese atmospheric precipitation lines, and a large intercept was present, indicating that atmospheric precipitation was not the major recharge source of groundwater in the two regions. The contribution rate of different NO3- sources in shallow groundwater around Erhai Lake was the highest for soil organic nitrogen （53.77%）, followed by nitrogen fertilizer （21.75%） and manure and sewage （21.55%）, and atmospheric deposition nitrogen （2.93%） was the lowest. Denitrification occurred in the transformation process of nitrogen in groundwater. The contribution rate of different NO3- sources in shallow groundwater around Chenghai Lake was manure and sewage （44.88%） > soil organic nitrogen （37.03%） > nitrogen fertilizer （16.17%） > atmospheric deposition nitrogen （1.92%）, and nitrification occurred in the transformation process of nitrogen in groundwater. The climate type significantly affected the shallow groundwater level, altering the migration and transformation process of nitrogen, thereby affecting the nitrogen concentration in groundwater and the contribution of NO3- as the chief source. However, the major source of NO3- was not affected by the climate type； however was more affected by land use, agricultural activities, and manure treatment methods.

Exploring the role of environmental literacy and social norms in farmers' LMTT adoption: evidence from China

PurposeClimatic changes caused by greenhouse gases (GHGs) emissions are an urgent challenge for all regions around the globe while the livestock sector is an important source of GHGs emissions. The adoption of low-carbon manure treatment technology (LMTT) by farmers is emerging as an effective remedy to neutralize the carbon emissions of livestock. This paper aims to incorporate environmental literacy and social norms into the analysis framework, with the aim of exploring the impact of environmental literacy and social norms on farmers' adoption of LMTT and finally reduce GHGs emission and climate effects.Design/methodology/approachThis research survey is conducted in Hebei, Henan and Hubei provinces of China. First, this research measures environmental literacy from environmental cognition, skill and responsibility and describes social norms from descriptive and imperative social norms. Second, this paper explores the influence of environmental literacy and social norms on the adoption of LMTT by farmers using the logit model. Third, Logit model's instrumental approach, i.e. IV-Logit, is applied to address the simultaneous biases between environmental skill and farmers’ LMTT adoption. Finally, the research used a moderating model to analyze feasible paths of environmental literacy and social norms that impact the adoption of LMTT by farmers.FindingsThe results showed that environmental literacy and social norms significantly and positively affect the adoption of LMTT by farmers. In particular, the effects of environmental literacy on the adoption of LMTT by farmers are mainly contributed by environmental skill and responsibility. The enhancement of social norms on the adoption of LMTT by farmers is mainly due to the leading role of imperative social norms. Meanwhile, if the endogeneity caused by the reverse effect between environmental skill and farmers’ LMTT adoption is dealt with, the role of environmental skill will be weakened. Additionally, LMTT technologies consist of energy and resource technologies. Compared to energy technology, social norms have a more substantial moderating effect on environmental literacy, affecting the adoption of farmer resource technology.Originality/valueTo the best of the authors’ knowledge, a novel attempt is made to examine the effects of environmental literacy and social norms on the adoption of LMTT by farmers, with the objective of identifying more effective factors to increase the intensity of LMTT adoption by farmers.

Survivability of low pathogenic avian influenza virus in aqueous poultry manure fertilizer

Avian influenza has been a growing problem in the United States for decades. Low pathogenic avian influenza (LPAI) virus causes low morbidity, while highly pathogenic avian influenza (HPAI) has a devastating effect on the poultry industry causing high morbidity and mortality worldwide. Manure from large and small poultry operations is spread on crop fields as a fertilizer. During an outbreak of avian influenza in a farm it is critical to adequately process the manure to kill the virus before its use in agriculture. Aqueous extraction of poultry manure at high temperature (55-65°C) is an attractive method for treatment of poultry manure, which extracts the nutrients and kills harmful microbes from the manure. The end product is a nutrient rich liquid that can be safely applied to fields or used in hydroponic operations, with nutrients that are more bioavailable to the plant compared to dry litter. However, we do not know whether aqueous high temperature extraction processes completely kill avian influenza virus present in the manure. Our aim in this study was to determine the competence of the aqueous extraction of poultry manure on avian influenza virus inactivation. We optimized the procedure using a LPAI virus isolate in a biosafety level 2 cabinet. Our data indicated that LPAI virus including the hemagglutinin protein of the virus were completely destroyed when the poultry manure was processed by aqueous extraction at temperatures ≥ 55°C for one hour. Future research will identify the conditions required for inactivating HPAI virus using this optimized procedure by performing the study in a BSL3 facility.

Carbon‐to‐nitrogen stoichiometry of organic amendments regulates microbial biomass growth and nitrogen mineralization in soil

AbstractThe carbon‐to‐nitrogen (C:N) ratio of organic amendments regulates nutrient cycling in soil through its influence on microbial activity. Where an organic amendment has a C:N ratio sparingly higher than that of soil microbes (C:N ratio 6.7—8.7), meeting microbial requirements of carbon and nitrogen may promote microbial biomass growth and nitrogen mineralization. Here we sought to understand the microbial response to the addition of organic amendments with varying C:N ratios and subsequent changes in nitrogen mineralization and plant nitrogen uptake. Dried insect larvae, beef feedlot manure and mixtures of beef feedlot manure with insect larvae or sugarcane residue were used as soil amendments to create a gradient of molar C:N ratios (Cm:Nm) ranging from 6 to 28. An untreated control treatment with a C:N ratio of 17 was also included. Sorghum (Sorghum bicolor L.) was grown in control and organic matter amended soils for 20 days after germination. The mixture of beef feedlot manure and insect larvae treatment (Cm:Nm = 9.7) had on average 68% higher microbial biomass compared with the other treatments. Beef feedlot manure with Cm:Nm ratio of 11 did not influence microbial biomass growth. The concentration of mineral nitrogen was highest in the insect larvae (Cm:Nm = 6) treatment, where 23% of the plant nitrogen was derived from the insect larvae as indicated by the δ15N of plant dry matter. We observed both carbon and nitrogen contents in the organic amendment determine microbial biomass growth and nitrogen mineralization in soil. The results presented here demonstrate that microbial response to organic amendments determines the availability of mineral nitrogen in soil.

Effect on Growth Performance and Nutritive Value of Cultivated Azolla filiculoides As An Alternative Feedstuff for Ruminant.

Azolla filiculoides is a tiny, free-floating aquatic fern and has a potential alternative protein and fibre source for ruminants, was investigated for its cultivation optimisation and feedstuff suitability. Study 1 was conducted to investigate the influence of different fertiliser types (control, broiler manure, sheep manure, cow manure) and concentrations (0.25 g/L-1.25 g/L) on the growth performance (fresh weight, doubling time, relative growth rate) and nutrient composition (dry matter, ash, crude protein, crude fibre, crude fat) of A. filiculoides. The optimised type of fertiliser and concentration in Study 1 were further adopted in Study 2 to evaluate the effect of different fertiliser processing methods on the growth performance, nutritive value and in vitro rumen digestibility of A. filiculoides upon cultivation. The findings in Study 1 showed that cultivation of A. filiculoides using sheep manure at the concentration of 1.00 g/L is the best resulted in the shortest doubling time (3 to 5 days) and produced fresh weight (FW), relative growth rate (RGR), crude protein (CP) and crude fibre (CF) at 132.2 g/m2, 0.32 g/g/day, 21.2% DM-1 and 14.4% DM-1, respectively. Furthermore, unprocessed sheep manure (T3) exhibited superior (p < 0.05) fresh weight, relative growth rate, nutrient composition and fibre components compared to the burned manure treatment (T2). In vitro digestibility analysis discovered that T3 achieved a 24-hour accumulated gas production of 86.9 mL DM-1, with in vitro dry matter digestibility (IVDMD), in vitro organic matter digestibility (IVOMD) and metabolisable energy (ME) of 82.9%, 43.7% and 5.8 MJ/kg DM, respectively. These findings suggest that Azolla filiculoides cultivation can be economically optimised using 1.00 g/L unprocessed sheep manure (fresh manure), potentially serving as a self-produced, nutritious feedstuff for ruminants.

The effect of cow manure amendment and the ratio of gold mine tailings on sweet potato gold phytomining

Artisanal and small-scale gold mining has commonly used the mercury amalgamation method for gold ore extraction. The processing waste or tailings often contain gold and other metals. This study examined the effects of cow manure amendment and the ratio of gold mine tailings on sweet potato (Ipomoea batatas L.) gold phytomining. The pot experiment was conducted in the Faculty of Agriculture greenhouse at Padjadjaran University in Indonesia. The sweet potato MZ119 clone (an orange-fleshed sweet potato) was planted on a polybag (40 x 40 cm) consisting of 10 kg of planting media, which was a mixture of gold mine tailing and soil. The design used was a completely randomized design factorial with three replications. The first factor was ratios of gold mine tailing consisting of three levels, namely 30%, 50%, 70%, and 100% (w/w). The second factor was doses of organic manure, namely without cow manure, 250 g pot-1, 500 g pot-1, and 750 g pot-1. The results demonstrated that the application of cow dung and the gold mine tailings ratio (w/w) had a significant (p = 0.05) effect on plants' dry weight biomass, gold accumulation, and gold phytomining by sweet potato. The highest gold mass yield of 0.066 mg gold plant-1 was achieved by a 50% (w/w) gold mine tailing ratio and 750 g pot-1 cow manure treatment.

Can soluble organic fertilizers and/or manure reach the agronomic and environmental performance of synthetic fertilizers in drip‐fertigated crops?

AbstractThe substitution of synthetics by organic fertilizers, which is the current pillar of circular economy, has been broadly evaluated. However, varying results were obtained on nitrous oxide (N2O) and nitric oxide (NO) emissions as well as crop yields. Besides, in irrigated semi‐arid croplands, drip fertigation has been suggested to be an effective practice for mitigating N2O and NO emissions while maintaining or enhancing agronomic performance. However, the promising combination of drip fertigation and organic fertilization remains poorly studied. By setting up melon (Cucumis melo L.) during 2022, and maize (Zea mays L.) during 2023, we aimed to evaluate the effect of different combinations of nitrogen (N) fertilizers: control without N fertilization, 100% of the N rate as solid manure (100OrM), 50% of the N rate as solid manure and 50% as urea (50OrM–50Syn), 50% of the N rate as solid manure and 50% as soluble organic (50OrM–50OrS), 100% of the N rate as urea (100Syn) and 100% of the N rate as soluble organic (100OrS). Urea and soluble organic fertilizers were supplied via drip fertigation. N‐oxides (N2O and NO), methane (CH4) and ecosystem respiration (CO2) fluxes, mineral N (ammonium [NH4+] and nitrate [NO3−]), dissolved organic carbon (DOC) and crop parameters were analysed. As regards N2O, no differences were observed between treatments in melon crop, whereas in maize crop, the cumulative emissions were the highest in 100OrM, followed by 50OrM–50Syn. Regarding NO cumulative emissions, in the melon crop were significantly lower in 50OrM–50Syn and 50OrM–50OrS between 34%–54%, compared with 100OrM and 100Syn. In the maize crop, the highest cumulative NO emission was also detected in solid manure treatment. The agronomic response of melon to N fertilization was only detected for total soluble solids (with maximum values in the 100Syn treatment). The combination of solid manure and top‐dressing urea or soluble organic fertilizer prevented the penalties in N use efficiency, which were observed in 100Syn and 100OrS. Therefore, the combination of conventional solid manure at seeding and soluble organic fertilizer at dressing (applied by drip fertigation) was the most sustainable strategy from agronomic and environmental viewpoints in Mediterranean irrigated agroecosystems.

Effects of hydrothermal pretreatment on sulfadiazine degradation during two-stage anaerobic digestion of pig manure

Antibiotics in animal manure pose significant risks to the environment and health. While anaerobic digestion (AD) is commonly used for pig manure treatment, its efficiency in antibiotic removal has been considerably limited. This study investigated the impact of hydrothermal pretreatment (HTP) on sulfadiazine (SDZ) removal in a two-stage AD system. Results indicated that the HTP process reduced SDZ concentration by 40.61%. Furthermore, the SDZ removal efficiency of the AD system coupling HTP increased from 50.90% to 65.04% compared to the untreated system. Biogas yield was also improved by 26.17% while maintaining system stability. Changes induced by HTP in the microbial communities revealed that Firmicutes, Bacteroidetes, Caldatribacteriota, and Proteobacteria emerged as the primary bacterial phyla. Following HTP, the relative abundance of Prevotella, which exhibited a strong negative correlation with SDZ concentration, increased significantly by 25-fold in the acidogenic stage. Proteiniphilum, Syntrophomonas and Sedimentibacter showed notable increases in the methanogenic stage after HTP. The N-heterocyclic metabolism carried out by Prevotella might have been the predominant SDZ degradation pathway in the acidogenic stage, while the benzene ring metabolism and hydroxylation by the Proteiniphilum emerged as the primary degradation pathways in the methanogenic stages. Furthermore, biodegradation intermediates were proven to be less toxic than SDZ itself, indicating that the HTP-enhanced two-stage AD process could be a viable way to lower the environmental risks associated with SDZ. The findings from this study provide valuable insights for removing SDZ from the environment via two-stage AD.

Mitigating water deficit stress in lemon balm (Melissa officinalis L.) through integrated soil amendments: A pathway to sustainable agriculture.

Lemon balm (Melissa officinalis L.) is a valuable medicinal plant, but its growth can be significantly impacted by drought stress. This study aimed to mitigate the adverse effects of water deficit stress on lemon balm biomass by integrating poultry manure compost, poultry manure biochar, NPK fertilizer, Trichoderma harzianum, Thiobacillus thioparus, and elemental sulfur as soil amendments. The experiment was conducted in a greenhouse using a completely randomized design with a factorial arrangement, consisting of three replicates. It included a water deficit stress factor at three levels (95-100%, 75-80%, and 55-60% of field capacity) and a soil amendment treatment factor with eleven different fertilizer levels. Treatments included control (no amendment), NPK fertilizer, poultry manure compost, poultry manure biochar, and combinations of these with T. harzianum, T. thioparus, and elemental sulfur under various water deficit levels. Water deficit stress significantly reduced photosynthetic pigments, gas exchange parameters, chlorophyll fluorescence, relative water content, and antioxidant enzyme activity, while increasing membrane permeability and lipid peroxidation in lemon balm plants. However, the integrated application of organic, biological, and chemical amendments mitigated these negative impacts. The combined treatment of poultry manure compost, poultry manure biochar, NPK fertilizer, T. harzianum, T. thioparus, and elemental sulfur was the most effective in improving the morpho-physiological properties (1.97-60%) and biomass (2.31-2.76 times) of lemon balm under water deficit stress. The results demonstrate the potential of this holistic approach to enhance the resilience of lemon balm cultivation in water-scarce environments. The integration of organic, biological, and chemical amendments can contribute to sustainable agricultural practices by improving plant morphological and physiological properties and plant performance under drought conditions.

Растеж и минерален състав на тютюн Виржиния в отговор на минерално торене и биостимуланти

The influence of mineral fertilization and two biostimulants (microbial inoculant Mycoplant® and protein hydrolysate (PH) Trainer®) on the growth and mineral composition of Virginia tobacco was studied in field and pot experiments on Rendzic Leptosol. The seedlings of the conventional technology (manure+mineral nitrogen fertilizer) had the highest weight and the highest concentration of N and Ca in the above-ground biomass. Biostimulants also had a positive effect on plant weight and the concentration of macro- and micronutrients. Microbial inoculant Mycoplant and PH Trainer increased seedling weight (fresh and dry) by 16.8% - 22.5% and 8% - 12%, respectively, compared to the manure treatment. The microbial inoculant containing AM fungi increased seedling N, P and Mg concentration by 8%, 9% and 13%, respectively, compared to manure treatment. The concentrations of Fe, Mn, Zn and Cu also increased when Mycoplant was applied. The application of a PH-based biostimulant Trainer resulted in higher concentration of N (by 11%) and Mg (by 4%) in seedlings. Leaf area and leaf weight (pot experiment) were positively affected by compound fertilizer application. Biostimulants Mycoplant and Trainer had a weaker positive effect on these indicators. The application of compound NPK fertilizer significantly increased the concentration of N, P and K in the leaves. Biostimulants also improved the uptake of essential nutrients by tobacco plants. The microbial inoculant significantly increased the concentration of Fe in the leaves - by 25.5% compared to the control. The concentration of N was increased by 14.3% when PH Trainer was applied.

Effect of Different Tillage and Organic Inputs on Soil Properties and Yield of Cotton on Vertisols

The present investigation was carried out at Research Farm, Department of Soil Science, Dr. PDKV, Akola during Kharif 2023-24 to study the effect of different tillage practices and organic inputs on soil properties and yield of cotton on Vertisols. Intensive tillage accelerates the loss of soil organic carbon (SOC) and reduces soil quality and yields, particularly in rainfed areas. This is further worsened by imbalanced fertilization and insufficient recycling of organic residues. Conservation tillage, when combined with organic inputs like FYM, vermicompost and phospho-compost, can help to restore soil structure, increase SOC and promote sustainable agricultural practices. The study aimed to assess the effect of different tillage practices and organic inputs on soil properties and on yield of cotton. The factorial randomized block design with two factors and four tillage treatments as factor A and four sources of manure as factor B were adopted. The treatments were composed of factor A consisting of four tillage operations [conventional tillage (T1), reduced tillage (T2), minimum tillage (T3) and zero tillage (T4)] and factor B consisting of organic manures such as farmyard manure (10 t ha-1) (M1), vermicompost (5 t ha-1) (M2), phospho-compost (5 t ha-1) (M3) and no manure (M4) replicated thrice. The results clearly indicated that conventional tillage resulted in the significantly highest seed cotton yield (14.10 ha-1), stalk yield (27.78 ha-1), total uptake of N (46.46 ha-1), P (7.86 ha-1) and K (33.05 ha-1) relative to other tillage practices examined. Among the organic manure treatments the highest seed cotton yield (11.21 ha-1), stalk yield (21.95 ha-1), total N (37.27 ha-1), P (6.57 ha-1) and K (31.25 ha-1) uptake by cotton was observed with phospho-compost application. Based on the observed results, it was notable that the available soil N, P and K were significantly influenced by the distinct tillage practices and organic manures. Among the tillage practices, the highest content of available soil N (182.14 kg ha-1), P (17.14 kg ha-1) and K (312.95 kg ha-1) were exhibited by the reduced tillage. The use of vermicompost resulted in the highest available soil N (185.93 kg ha-1) and K (316.68 kg ha-1), while the highest available soil P (18.22 kg ha-1) was observed with phospho-compost. The results revealed that conventional tillage combined with phospho-compost improves cotton yield and nutrient uptake, while reduced tillage along with the application of vermicompost and phospho-compost improves soil fertility. Therefore, combined use of tillage and organic inputs could be beneficial for enhancing soil properties and higher productivity of cotton in Vertisols as well as the whole of Maharashtra.

Manure sterilization reduced antibiotic resistance genes in lettuce endophytes

Livestock manure is commonly utilized as a fertilizer in agricultural system, potentially resulting in the dissemination of antibiotic resistance genes (ARGs) to plants. This raises concerns about the efficiency of manure treatment methods in reducing ARGs. Although sterilization treatment is frequently applied to mitigate the microbial loads, its efficacy in reducing ARGs remains unclear. This study investigated the impact of sterilized vs. unsterilized manure on the profiles of ARGs and bacterial community in a hydroponic lettuce system. After the 20-day cultivation period, 68 ARGs and 18 mobile genetic elements (MGEs) were identified. Manure sterilization not only promoted lettuce growth but also resulted in a reduction of ARG and MGE subtypes by 50.00%–86.21% in lettuce endophytes. Proteobacteria, Bacteroidota, and Firmicute were the dominant phyla, with a notable reduction of 70.05%–99.01% in Firmicutes by sterilization in lettuce endophytes. The predominant human pathogenic bacteria genera were Pseudomonas, Sphingomonas, and Bacillus, and sterilization effectively reduced the presence of Bacillus. Moreover, the estimated intake of ARGs in leaf endophytes ranged from 2.88 × 105 to 9.16 × 108 copies per day, including 6 high-risk ARGs. Manure sterilization reduced the association between high-risk ARGs and human pathogenic bacteria. The interaction between bacterial community and MGEs shaped ARG patterns with a contribution of 81.87%. Overall, these findings highlighted the critical role of sterilization in reducing ARGs in the manure used for hydroponic agriculture, providing guidance in waste management, crop safety, and public health.

Nitrogen use efficiencies, flows, and losses of typical dairy farming systems in Inner Mongolia

Dairy farming is a notable source of nitrogen (N) emissions, impacting both atmospheric and aquatic ecosystems, thus necessitating a detailed analysis of nutrient dynamics to curtail nutrient wastage. However, N flow variability and its environmental ramifications differ markedly among dairy farms, and a holistic understanding of these differences is lacking in Inner Mongolia, the biggest dairy production province in China. Utilizing data from 187 dairy farms and employing the NUFER-farm model, this study assessed N flows, N use efficiency (NUE), and N losses across four predominant dairy farming systems in Inner Mongolia. These systems include traditional pastoral dairy farms (PF), smallholder dairy farms with croplands (SF), industrial landless farms (IDF), and coupled dairy cattle and cropland-intensive farms (CDF). Our findings indicate considerable differences in N flows, NUE, and losses among the systems. On average, N deposition and N fertilizer were the primary N sources for PF and SF, respectively, whereas IDF and CDF derived over 90% of their N inputs from purchased feeds. PF and SF recycled all available manure N on-farm, whereas IDF and CDF recycled only approximately 36% of the total available manure N. N losses constituted 39–72% of total N outputs, with ammonia emissions accounting for 68–73% of total N losses across all farm types. In particular, PF had a higher N loss per kilogram of dairy product than other systems. Farm-level NUE ranged from 17 to 35%, with manure management practices showing significant variability, underscoring the potential for enhanced strategies to reduce N losses through improved manure treatment.