Non-fertilized Treatments Research Articles

Effect of four different types of vermicomposts on okra productivity and farm income

Organic based fertilizers is crucial for maintaining soil fertility, increasing crop production, and mitigating climate change. Among various organic fertilizers, vermicompost (VC) has been found to be one of the promising options for enhancing soil fertility and productivity. However, there are limited studies on the agronomic effects of vermicomposts in Nepal. In this study, a pot culture experiment was conducted inside a greenhouse to assess the agronomic and economic effects of four different commercially available vermicomposts, available in both reduced and original moisture forms, on okra. Nine treatments with three replications were arranged in a completely randomized design (CRD). These treatments included Divya vermicompost with both reduced (DvRM: 28.82 %) and original moisture (DvOM: 62.17 %); Praramva vermicompost with reduced (PvRM: 29.63 %) and original moisture (PvOM: 54.65 %), Bio-Comp vermicompost with reduced (BvRM: 26.75 %) and original moisture (BvOM: 49.77 %), Sathi vermicompost with reduced (SvRM: 28.52 %) and original moisture (SvOM: 65.18 %), and a control (CK: non-fertilized treatment). All VC treatments, whether in reduced or original moisture forms, showed better performance on plant growth parameters and fruit yield compared to the control. There was no significant difference between the four types of VCs, in either moisture form. The average number of fruits per pot in VC treatments (ranging from 5.5 to 8.0 fruits per pot) increased by 94 % compared to CK (3.5 fruits). Similarly, total fruit yield increased by 126 % in VC treatments (ranging from 16213 kg ha−1 to 23193 kg ha−1) compared to the CK (8260 kg ha−1). The benefit to cost ratio (B:C) of all the VCs was above 1 (B:C > 1), ranging from 1.00 to 1.59, illustrating the economic benefit of using vermicompost in okra cultivation. The findings suggest that farmers should consider the widespread use of vermicomposts to increase both crop productivity and farm profitability, thereby sustaining their livelihoods.

Effect of synthetic fertilization dose on the diameter increase, height and mortality of Cinchona officinalis L. (Rubiaceae)

Cinchona officinalis, is a South American tree species, commonly used for medicine, and is currently threatened by agricultural expansion and cattle ranching. The objective was to determine the effect of chemical fertilization on the nursery growth to increase growth potential and survival of C. officinalis. A completely randomized design with six treatments and three replicates was used; 20 C. officinalis plants were used per replicate. Two months after transplanting the C. officinalis seedlings to the polyethylene bags, inorganic fertilizer (YaraMila® HYDRAN) was applied. Monthly evaluations were carried out and the number of dead plants, plant height, diameter and number of leaves were recorded. The highest mortality rate was recorded when fertilizer was applied (73%) while in the non-fertilized treatment mortality reached 36%. Regarding the increase in height, diameter and number of leaves in all cases, the best results were obtained in the fertilized treatments, exceeding by 85, 70 and 17% (respectively) those obtained in the treatment to which fertilization was not applied. This study shows the effects that the application of fertilizers to C. officinalis plants at the nursery level can have on growth and mortality variables, the results suggest the use of this product for a sustainable and large-scale production of this species taking into consideration the appropriate dosage.

Measurement report: Exchange fluxes of HONO over agricultural fields in the North China Plain

Abstract. Nitrous acid (HONO) is a crucial precursor of tropospheric hydroxyl radicals, but its sources are not fully understood. Soil is recognized as an important HONO source, but the lack of measurements of soil–atmosphere HONO exchange flux (FHONO) has led to uncertainties in modeling its atmospheric impacts and understanding the reactive nitrogen budget. Herein, we conduct FHONO measurements over agricultural fields under fertilized (FHONO-NP, normal fertilization and irrigation) and non-fertilized (FHONO-CK, normal irrigation but no fertilization) treatments. Our results show that nitrogen fertilizer use causes a remarkable increase in FHONO-NP. FHONO-NP exhibits distinct diurnal variations, with an average noontime peak of 152 ng N m−2 s−1. The average FHONO-NP within 3 weeks after fertilization is 97.7±8.6 ng N m−2 s−1, around 2 orders of magnitude higher than before fertilization, revealing the remarkable promotion effect of nitrogen fertilizer on HONO emissions. We also discuss other factors influencing soil HONO emissions, such as meteorological parameters and soil properties/nutrients. Additionally, we estimate the HONO emission factor of 0.68±0.07 % relative to the applied nitrogen during the whole growing season of summer maize. Accordingly, the fertilizer-induced soil HONO emission is estimated to be 22.3 and 60.8 Gg N yr−1 in the North China Plain (NCP) and mainland China, respectively, representing a significant reactive nitrogen source. Furthermore, our observations reveal that soil emissions sustain a high level of daytime HONO, enhancing the atmospheric oxidizing capacity and aggravating O3 pollution in the NCP. Our results indicate that to mitigate regional air pollution effectively, future policies should consider reactive nitrogen emissions from agricultural soils.

PSII-14 Chemical Composition of Tropical Forage Fertilized with Different Sources of Nitrogen Fertilizers

Abstract Nitrogen fertilization can improve the chemical composition of tropical forages, as nitrogen is required at all stages of plant development. The aim of this study was to verify the chemical composition of Urochloa brizantha cv. marandu fertilized with different sources of nitrogen fertilizers from the following treatments: without nitrogen fertilization (CO), fertilization with urea (UR), fertilization with ammonium nitrate (NI) and fertilization with ammonium sulfate (SA). The study was carried out from December 2021 to April 2022, in the cerrado biome of Brazil at the FCAV/UNESP Forage Sector, Jaboticabal Campus, during the rearing phase of Nelore cattle, non-castrated males kept on pasture, managed in a continuous stocking system and variable load capacity. In treatments with fertilization, 150 kg of N· ha-1 were applied, divided into 3 applications. The design used was in randomized blocks (DBC). The evaluation of the chemical composition of the forage was carried out from collections every 28 days of samples of the fraction of the forage consumed by the animals through the hand-plucking method. The samples were dried at 55ºC for 72 hours and ground in a Willey mill, with a 1 mm mesh sieve. The chemical composition of the forage was estimated by spectroscopy in the near infrared light region, NIRS (Near Infrared Spectrometer), using a modular FT-NIR spectrometer. The data obtained were submitted to ANOVA and Tukey's test (P ≤ 0.05), using the statistical program R, version 3.4.4. Nitrogen fertilization significantly increased the organic matter content of the forage (P = 0.001). The organic matter content of the non-fertilized treatment was 91.97%, while the average of the fertilized treatments was 92.22%. The percentage of crude protein in the forage also showed a significant difference (P < 0.001) between the non-fertilized treatment, which had an average of 10.64%, and the fertilized treatments, which had an average of 17.75%. The neutral detergent fiber and acid detergent fiber components also differed from the application of nitrogen fertilizer (P < 0.001) but did not differ between the types of fertilizers. The neutral detergent fiber content was significantly different (P < 0.001) between the non-fertilized treatment (59.21%) and the fertilized treatments (54.30%). The observed data for acid detergent fiber were 31.46% for the treatment without the use of fertilizers and 30.24% for the treatments with the use of fertilizers. Non-fibrous carbohydrates and liguinin components were also analyzed, but showed no difference between treatments, P = 0.078 and P = 0.209, respectively. This study confirms that the chemical composition of Urochloa brizantha cv. Marandu can be significantly improved through the application of nitrogen fertilizers. However, our results showed no significant difference between the types of fertilizers tested.

Differences of SOC storage and stability between soil layers influenced by long-term fertilization in a typical paddy soil of Southern China

BackgroundThe contribution of long-term fertilization to soil organic carbon (SOC) storage has been of great concern. To assess the effects of long-term fertilization on SOC storage and stability in top and sub-soil layers, soil samples were collected from a 29-year field experimental station in a typical paddy soil in southern China. The SOC storage of whole soil and SOC fractions was quantified at three soil depths (0–20, 20–40, 40–60 cm) under four treatments: no fertilization (Control), a combination of nitrogen, phosphorus and potassium (NPK), double the rates of NPK (2NPK), NPK plus manure (NPKM).ResultsThe increase of Cinput-total was significantly higher than that of SOC storage among different treatments (p < 0.05), indicating that soil fixation of exogenous carbon is limited. Besides, the SOC accumulation and sequestration rates patterned as NPKM > 2NPK > NPK, and these rates were higher at 0–20 cm depth as compared to other depth intervals. Furthermore, for the whole profile, the SOC storage of active pool was higher in the Control (39.6 t C ha−1) than in other treatment (36.2 t C ha−1, p < 0.05). Whereas, fertilization increased the SOC storage of passive pool, ranked as NPKM > 2NPK≈NPK > Control (p < 0.05), indicating that fertilization, especially organic combined with inorganic fertilization, improved SOC stability. From the perspective of soil layers, the difference of SOC storage among treatments for passive pool was mainly resulted from the difference at surface soil, and for active pool were the deeper layers. Additionally, manure application increased the difference among soil layers.ConclusionThis study concluded that non-fertilized treatment could improve the SOC storage of active pool especially in deep soil layers, while fertilization especially manure application could improve the SOC storage and stability in surface soil and increased the difference among soil layers.Graphical

Modeling sorghum-cowpea intercropping for a site in the savannah zone of Mali: Strengths and weaknesses of the Stics model

Intercropping is a key entry point for sustainable intensification of cropping systems in sub-Saharan Africa where variable rainfall conditions prevail. Crop simulation models can complement field experiments to assess the agronomic and environmental performances of intercropping systems under diverse climatic conditions, including hypothetical future climate. So far, crop models that can handle intercropping, such as STICS, have not often been extensively evaluated for tropical conditions and for species grown by farmers in sub-Saharan Africa. The objective of this study was to evaluate the performance of the calibrated STICS model to simulate sorghum-cowpea intercropping systems in rainfed conditions in West Africa. We used data from field experiments conducted at the N'Tarla Agronomic Station in Mali in 2017 and 2018. Two varieties of sorghum (local and improved) with contrasting photoperiod sensitivities were grown as sole crop and intercropped with cowpea, with additive design. Two sowing dates and two levels of mineral fertilization were also investigated. Model simulations were evaluated with observed data for phenology, leaf area index (LAI), aboveground biomass, grain yield and in-season soil moisture. Large variations in aboveground biomass of sorghum and cowpea was observed in the experiment (i.e. 3.5 – 9.6 t/ha for sorghum and 0.4–2.5 t/ha for cowpea), owing to the treatments (i.e. sole vs intercrop, early vs late sowing, no fertilizer input vs fertilizer input). Such variations were satisfactorily reproduced by the model, with EF of 0.81 in calibration and 0.58 in evaluation (with relative rRMSE of 23 % and 43 %) across crops. Sorghum AGB simulations were more accurate (rRMSE of 21 % and EF of 0.54) than cowpea AGB simulations (rRMSE of 25 % and EF of −0.09). The two main observed features of the intercropping system were well reproduced by the model. Firstly, cowpea and sorghum aboveground biomass decreased with intercropping compared with sole cropping, and the decrease in cowpea biomass was greater than the decrease in sorghum biomass. Secondly, despite a reduction in sorghum and cowpea yield, Land Equivalent Ratio of the intercropping for aboveground biomass was always above one. With regard to grain yield, observed LER was above one only in the non-fertilized treatment. The model failed at reproducing this behavior, probably because of insufficiently accurate calibration of the process leading to grain yield formation: rRMSE for grain yield was 49 % in calibration and 41 % in evaluation. Based on these findings, we discuss avenues to improve model calibration and use the model to explore options for sustainable intensification in land constrained sub-Saharan Africa. • Accurate STICS simulations of intercropped sorghum and cowpea aboveground biomass. • Inaccurate STICS simulations of intercropped sorghum and cowpea grain yield. • The model can be used to start exploring inter-annual performance of intercropping. • Experiments looking at N dynamics in intercropping needed to refine calibration.

Responses to defoliation and fertiliser, corm development and chemical control of onion grass (Romulea rosea) in the Mediterranean environment of southern Australia

AbstractBackgroundOnion grass (Romulea rosea) is a common weed that infests native and improved pastures in the Mediterranean environments of southern Australia. It is a very challenging weed to control due to its distinctive growth and survival mechanisms involving corms.MethodsThree glasshouse experiments were conducted in Australia to investigate the response of onion grass to defoliation and fertiliser application, the development and growth of onion grass corms and the chemical control of the weed in winter and spring.ResultsDefoliating consistently to 1 cm above ground reduced corm weight by 84% compared with the control. Medium or high fertiliser application did not increase herbage mass of onion grass compared with the nonfertilised treatment. The corm weight of onion grass declined from Weeks 1 to 8 after emergence, remained at 53–60 mg dry matter (DM) corm−1 from Weeks 8 to 19 and then declined on average to 37 mg DM corm−1 up to Week 26 after emergence. New corms started to develop at Week 6 after emergence. A small proportion of the onion grass plants (7.5%) developed multiple new corms (3–6 corms) from a single old corm. The most effective herbicide control was a winter application of metsulfuron methyl or imazamox as an alternative product to protect clover.ConclusionsThis study has identified the growth and development patterns of onion grass corms, how the plant responded to defoliation and fertiliser application and effective chemical control of this weed. These findings have significant practical implications for the improvement of onion grass‐infested pastures.

Carbon-Phosphorus Coupling Governs Microbial Effects on Nutrient Acquisition Strategies by Four Crops.

Plants adjust root morphological and/or exudation traits in response to phosphorus (P) mobilization mediated by microorganisms. We hypothesized that straw application coupled with P fertilization would influence microbial P and then root nutrient-acquisition strategies related to crop growth. Root morphological (length and average diameter) and exudation traits (acid phosphatase and carboxylates) of Brassica chinensis, Solanum lycopersicum, Lactuca sativa, and Vigna unguiculata in response to microbial P dynamics were characterized in no-P and P-fertilized soil with/without straw addition. Straw addition increased the growth of fungi and bacteria, stimulating microbial P immobilization at day 24. The high microbial abundance was associated with four tested crops having short roots in straw-amended compared with no-straw soil at day 24. In straw-amended soil, B. chinensis and S. lycopersicum shifted toward root P-acquisition strategies based on fast elongation and strong carboxylate exudation from days 24 to 40. Such effective root P-acquisition strategies together with microbial P release increased shoot P content in S. lycopersicum in straw-amended compared with those without straw at day 40. Conversely, L. sativa and V. unguiculata produced short roots in response to the stable (or even increased) microbial P after straw addition till day 40. In straw-amended soil, high P application stimulated root elongation and carboxylate exudation in L. sativa and V. unguiculata, whereas carboxylate exudation by S. lycopersicum was decreased compared with the straw-amended but non-fertilized treatment at day 40. In summary, root P-acquisition strategies in response to microbial P differed among the tested crop species. Phosphorus fertilization needs to be highlighted when returning straw to enhance P-use efficiency in vegetable cropping systems.

Novel Approach for Statistical Interpretation: A Case Study from Long-Term Crop Production Experiments (Hungary)

In recent decades, the agricultural sector has witnessed rapid technological interventions from field to the production stage. Thus, the importance of these technological interventions must be strictly evaluated. The traditional statistical method often deems low statistical differences as a significant one, which cannot be considered effective from different perspectives. In this sense, the aim of this research was to develop a new statistical method for evaluating agricultural experiments based on different criteria; hence, the significant importance of the technological interventions can be clearly determined. Data were collected from of a long-term (13-year) crop production experiment (Central Europe, Hungary), which involved five different fertilization levels, along with non-fertilized treatment (control), two irrigation treatments (irrigated and non-irrigated), and 15–20 genotypes of maize. The output of this research showed that the classic statistical approach for testing the significant differences among treatments should be accompanied with our new suggested approach (i.e., professional test), which reflect whether treatments were professionally effective or not. Also, results showed that good statistical background is not enough for interoperating the analysis of agricultural experiments. This research suggested that erroneous conclusions can be avoided by merging classical and professional statistical tests, and correct recommendations could be provided to decision makers and farmers based on their financial resources.

Repeated Manure Application for Eleven Years Stimulates Enzymatic Activities and Improves Soil Attributes in a Typic Hapludalf

Animal manure may be a valuable resource for the development of agricultural sustainability. We proposed to verify the feasibility of applications of three types of animal manures to improve soil attributes and to sustain crop yields under intensive cropping and no-tillage systems. The field experiment was established in 2004 on Typic Hapludalf soil with pig slurry (PS), cattle slurry (CS), pig deep-litter (PL), mineral fertilizer (MF) and a non-fertilized treatment. From 2004 to 2015, were grown black oat, maize, forage turnip, black beans, and wheat. Soil samples were taken after winter 2014 and summer 2015, and submitted to chemical, physical, microbiological and biochemical analyses. Animal manures increased soil pH, but MF caused acidification of soil. The PL and CS applications reduced soil density, and increased total pore volume and hydraulic conductivity. Animal manures increased soil P fractions, total organic carbon, total nitrogen, stimulated soil respiration, and had higher activities of glucosidase and acid phosphatase. Wheat had its biggest dry matter and grain yields with MF, but maize grain yields with CS were higher than MF. All indicators pointed that application of animal manure converges to an interesting strategy to recycle nutrients at farmyard level and to contribute to global sustainability.

EFFECT OF POULTRY LITTER AS AN ORGANIC FERTILIZER, IN WATER QUALITY, PARASITIC ABUNDANCE, AND GROWTH NILE TILAPIA

Nile tilapia feed on plankton in natural environments. This food source can be increased in ponds through fertilization and can reduce feed expenses or improve fish performance when used as supplementary food. Organic fertilization is an alternative to commercial fertilization; however, its use increases concerns regarding water quality and sanitary aspects. This study aimed to evaluate the effects of the use of poultry litter as organic fertilizer on the physical and chemical parameters of water, gill ectoparasite metazoan abundance, and growth of Nile tilapia (Oreochromis niloticus) during the culture cycle lasting 240 days. Four earthen ponds, two fertilized with poultry litter and two non-fertilized ponds, as fertilized and non-fertilized treatments, respectively, were used. Stocking density was 3 fish per m2 with an average initial weight of 0.64 ± 0.15 g. The mean water quality values and the growth performance parameters of Nile tilapia did not show significant differences between the two treatments. The gill parasites found in the fish belonged to the class Monogenea, comprising two genera, Cichlidogyrus and Scutogyrus, with significant differences between treatments. The non-fertilized treatment showed a high abundance of parasites throughout the culture cycle months, with peak abundance in the months with low concentrations of dissolved oxygen in the water.

Optimizing N Fertilization for Increasing Yield and Profits of Rainfed Maize Grown under Sandy Loam Soil

The optimum dose of fertilizers for crops varies with soil, agro-ecology, and crop management practices. Optimizing application dose is critical to reduce nutrient loss to the environment and increase nitrogen use efficiency (NUE), crop yields, and economic return to farmers. An experiment was conducted to determine the optimum N dose for increasing maize (Zea mays L. cv, Manakamana-3) yield, NUE, and farm profits under rainfed conditions. Five levels of N (0, 60, 120, 180, and 240 kg ha−1), and a non-fertilized treatment were tested in a randomized complete block design with three replications. Effects of each treatment on yield and yield attributing traits, plant lodging and Sterility (plants with no cob or grain formation), NUE, and stay green trait of maize were recorded. Application of N above 120 kg ha−1 (N120) did not have any significant effects on yield and yield components. Nitrogen, at N120 and above, produced highly fertile plants (though sterility slightly increased at N180 and N240), higher N uptake, and lower dead leaf area (18–27%). N120 produced the highest agronomic; yield increase per unit of N application (AEN—26.89 kg grain kg−1 N) and physiological efficiency of N (PEN—42.67 kg grain kg−1 N uptake), and net benefit (USD 500.43). Considering agronomic, economic, and NUE factors, an N dose of 120 kg ha−1 was found optimum for the cultivation of rainfed maize (Manakamana-3) under sandy loam soil.

Effect of different N doses on maize yield and quality

The effect of N doses on the yield and nutritional values of the Sushi (FAO 340) maize hybrid were analysed in three years (2018, 2019, and 2020). The analyses were performed at the Látókép Experimental Station of the University of Debrecen on calcareous chernozem soil, in a striped, small-plot, non-irrigated long-term field experiment. In the experiment, in addition to the non-fertilized treatment (A0), the N-fertilizer doses were applied as basic fertilizer and top dressing. The 60 and 120 kg N ha-1 dose (A60, A120) applied as spring basic fertilizer were followed by two phases of top-dressing in V6 (V690, V6120) and V12 (V12150, V12180) phenophases; the amounts were +30 and +30 kg N ha-1. Maize yields were affected to varying degrees by crop year. The highest yields in 2018 and 2020 were recorded in the same V6150 treatment, while in 2019 the highest yield was obtained in the A120 treatment. Increasing the N doses resulted in an increase in the protein content of the maize kernel. Depending on the fertilizer treatments and the crop year effect, the protein content of maize kernels varied between 6.2–10.2 g x 100 g-1. In all three years, the protein content was the lowest in the control treatment (A0) and the highest in the V6150 treatment. The starch content ranged from 70.7 to 77.9 g x 100 g-1 in the average of the three years. In 2020, it was significantly higher in all nutrient treatments than in the other examined two years. The highest starch content - except for 2020 (A120, 77.9 g x 100 g-1) - was recorded in the A0 treatment (74.2, 72.3 g x 100 g-1). The oil content of maize kernels varied between the values of 3.8 and 5.2 g x 100 g-1 in the average of three years. In terms of oil content, the results for 2018 and 2019 can be considered the same, while in 2020 it was significantly lower. Fertilizer treatments did not significantly affect the oil content of maize in any of the years. The fertilizer dose applied in the V12 phenological phase was not effective in terms of yield and nutritional content (protein, starch and oil content).

Ammonium oxidizing bacteria and archaea vary with season under plastic film mulching and long-term fertilization

ABSTRACT Agronomic practices such as long-term use of plastic film mulching (PFM) and application of organic and inorganic fertilizers have profound effect on soil microbial community. However, there is limited information on the abundance and community structure of ammonia-oxidizers where these practices have been employed. In this study, we investigated soil ammonia oxidizers in a long-term application of fertilizer plots with or without PFM in two seasons of a maize-growing period. The fertilization treatments included: non-fertilizer control (CK), nitrogen fertilizer (N), organic manure (M), nitrogen fertilizer plus organic manure combined (MN). Real-time quantitative polymerase chain reaction (qPCR) of ammonia monooxygenase (amoA) genes revealed that the abundances of ammonia-oxidizing archaea (AOA) (1.0 x 107 to 2.0 × 1011 per copies g−1 dry soil weight) significantly (p < 0.05) out-numbered ammonia-oxidizing bacteria (AOB) (5.0 x 105 to 4.0 × 109 copies g−1 dry soil weight) abundances for June, July and October respectively. The phylogenetic analyses of denaturing gradient gel electrophoresis (DGGE) 16S rRNA gene revealed that AOB-uncultured Nitrosospira sp dominated bacterial ammonia oxidizers in fertilized and non-fertilized soils, regardless of PFM treatments for July and October. The non-fertilization treatment significantly increased bacterial richness (15.67 ± 0.33) under PFM treatment relative to fertilized treatments.

Chemical and spectroscopic characteristics of humic acid from a clay loam soil in Ontario after 52 years of consistent fertilization and crop rotation

Long-term fertilization and crop rotation can influence both organic C sequestration as well as the C composition of soils and the more resistant organic C compounds contained in humic acid (HA). This study examined the effects of fertilization and cropping type (monoculture corn (MC) and Kentucky bluegrass sod (KBS) and corn-oat-alfalfa-alfalfa rotation (RC)) on the HA composition of soil from a 52-year field study in southern Ontario, Canada. Humic acid samples were extracted from soil, and elemental analysis, infrared spectroscopy, solid state 13 C nuclear magnetic resonance spectra, and electron paramagnetic resonance methods were used to determine the influence of the cropping type on the characteristics of HA. Both fertilization and cropping type affected the chemical characteristics of HA. Fertilization led to a 5.9% increase in C, a 7.6% decrease in O, and lower O/C and (N + O)/C ratios in HA as compared to the corresponding non-fertilized treatments. Rotation resulted in a lower proportion of C (48.1%) and a greater (N + O)/C ratio (0.7) relative to monoculture cropping. Infrared spectroscopy analysis showed that HA contained more C-O groups in fertilized soil than in non-fertilized soil under MC and KBS. Fertilization increased the O-alkyl-C, phenolic-C, and free radical contents of HA relative to non-fertilization treatments. Rotation decreased the aliphatic and carboxyl groups and increased the O-alkyl, carbohydrate, aryl, and phenolic groups and free radicals, relative to MC and KBS. Both long-term crop rotation and fertilization dramatically modified the soil HA composition. Significant relationships were observed between the molecular composition of HA and soil organic C. Hence, humic acid characterization could be used as an indicator of the long-term sustainability of crop management practices.

The Influence of Different Fertilization Strategies on the Grain Yield of Field Peas (Pisum sativum L.) under Conventional and Conservation Tillage

Weather, tillage, and fertilization are the major factors affecting the grain yield of field peas (Pisum sativum L.). However, the impact of tillage and fertilization on yield is not well understood. Therefore, this experiment was initiated in 1999. In this manuscript, we report the data recorded during the period of 2011–2015 to quantify the impacts on yield. Field peas were planted in seedbeds prepared through conventional tillage (CT)—moldboard ploughing to the depth of 0.22 m; and minimum tillage (MT)—disking to the depth of 0.12 m. The crop received three fertilization treatments, including zero fertilization (control); nitrogen, phosphorus and potassium (NPK) mineral fertilization treatment; and NPK mineral fertilization plus the incorporation of pre-crop biomass. Five years’ average data indicated the highest yield on fertilized treatments (2.85–2.98 t ha−1 vs. 2.66 t ha−1) regardless of the tillage. When comparing the yield of fertilized treatments, the yield under CT (2.98 t ha−1) was significantly higher than that of MT (2.85 t ha−1). However, on non-fertilized treatments (less fertile plots), a higher yield was recorded under MT (2.71 t ha−1) compared with CT (2.40 t ha−1). Overall, the results of this study suggest that fertilizer application together with incorporation of the above-ground biomass of the previous crop may help sustain pea grain yield.

Long-term cropping and fertilization influences soil organic carbon, soil water repellency, and soil hydrophobicity

Long-term (58 yr) cropping and fertilization effects on soil water repellency were determined for a clay loam soil in southwestern Ontario, Canada by measuring soil organic carbon (SOC), soil water repellency index (RI), and soil hydrophobicity (SH). The 12 treatments (non-replicated) included fertilized and non-fertilized legume-based crop rotation (ROT) with four phases (corn–oat–alfalfa–alfalfa), continuous corn (CC), and continuous Kentucky bluegrass (KBG). We hypothesized that SOC, RI, and SH would be greater for each phase of the ROT versus CC, KBG versus CC and ROT, and fertilized versus non-fertilized treatments. Surface (0–10 cm) soil samples were collected in the spring of 2017. Laboratory measurements were conducted to determine SOC, RI (ratio of soil sorptivity to ethanol and water), and SH (ratio of hydrophobic CH– to hydrophilic CO– functional groups). Mean SOC and SH were greater (P ≤ 0.05) for each phase of the ROT versus CC (33% to 2.4 times), KBG versus CC (3.2–6 times) and each phase of ROT (2.2–2.8 times), and fertilized versus non-fertilized rotation oats and KBG (15%–30%). Mean RI was greater for KBG versus CC (4.8 times) and KBG versus each phase of the ROT (3.0–5.5 times) under fertilization only, greater for fertilized versus non-fertilized KBG (6.8 times), but similar for each phase of ROT versus CC. In general, legume-based rotations, perennial grass, and fertilizer enhanced SOC and SH, and to a lesser extent soil RI.

The Effect of Fertilization on Time Domain Reflectometry Probe Measurement Accuracy in the Field Experiment in Slovakia

Abstract The paper presents evaluation of the calibration method using side-by-side direct gravimetric and indirect time domain reflectometry (TDR) for soil moisture measurements to improve TDR measurement accuracy. Measurements were carried out at the experimental site Dolná Malanta (Slovakia) in 2017. Two non-fertilized treatments – without biochar (B0 + N0) and with biochar at 20 t·ha−1 (B20 + N0) – and two fertilized treatments – with biochar at 20 t·ha−1 and N fertilizer at dosages of 160 kg·ha−1 (B20 + N160) and 240 kg·ha−1 (B20 + N240) – were used in this study. The study also investigates the relationship between both used methods of soil water content determination. A strong correlation between both methods was observed. In case of (B0 + N0); (B20 + N0); (B20 + N160); and (B20 + N240), it was 0.93; 0.97; 0.97; and 0.98, respectively. However, it is assumed that the TDR probe may show errors in the results without prior calibration. It was observed that the accuracy of TDR device was lower for fertilized treatments in contrast to the gravimetric method and non-fertilized treatments. It is assumed that the higher measurement inaccuracy might be increased by salt concentration in the soil as a result of applied N fertilizer.

Changes in Photo-Protective Energy Dissipation of Photosystem II in Response to Beneficial Bacteria Consortium in Durum Wheat under Drought and Salinity Stresses

The present research aimed at evaluating the harmless dissipation of excess excitation energy by durum wheat (Triticum durum Desf.) leaves in response to the application of a bacterial consortium consisting of four plant growth-promoting bacteria (PGPB). Three pot experiments were carried out under non-stress, drought (at 40% field capacity), and salinity (150 mM NaCl) conditions. The results showed that drought and salinity affected photo-protective energy dissipation of photosystem II (PSII) increasing the rate of non-photochemical chlorophyll fluorescence quenching (NPQ (non-photochemical quenching) and qCN (complete non-photochemical quenching)), as well as decreasing the total quenching of chlorophyll fluorescence (qTQ), total quenching of variable chlorophyll fluorescence (qTV) and the ratio of the quantum yield of actual PSII photochemistry, in light-adapted state to the quantum yield of the constitutive non-regulatory NPQ (PQ rate). Our results also indicated that the PGPB inoculants can mitigate the adverse impacts of stresses on leaves, especially the saline one, in comparison with the non-fertilized (control) treatment, by increasing the fraction of light absorbed by the PSII antenna, PQ ratio, qTQ, and qTV. In the light of findings, our beneficial bacterial strains showed the potential in reducing reliance on traditional chemical fertilizers, in particular in saline soil, by improving the grain yield and regulating the amount of excitation energy.

Effect of human urine application on cabbage production and soil characteristics

Abstract The aim of this study was to examine the effect of human urine on soil quality and salinity through repeated applications, and compare it with the effects of synthetic fertilizer and non-fertilized treatments. Six different fertilizer mixtures were applied to pots of head cabbage: 100% tap water, 100% urine, 1:1 urine and tap water, 1:2 urine and tap water, 1:3 urine and tap water, and synthetic fertilizer. The study design was completely randomized design (CRD) with three replications of pot-based experiments. The growth and yield parameters of producing head cabbage (Brassica oleracea) among treatments were compared. Soil residual test of the optimum treatment was also conducted for the optimum treatment to examine the effect on its characteristics. The optimum yield was obtained from the application of 1:3 of urine and water, and comparable to the synthetic fertilizer (F = 21.78; p = 0.964). The difference in the electrical conductivity of soil was statistically significant (F = 2.324; p = 0.049) after three rounds of applications which should be considered during urine fertilizer utilization. Generally, urine contains nutrients, which can substitute synthetic fertilizer, at a dilution factor of three. However, education should be delivered to enhance public acceptance and to create awareness on urine collection, storage and application for sustainable utilization.