Efficiency Of Fertilizer Use Research Articles

Stomatal conductance drives variations of yield and water use of maize under water and nitrogen stress

Water and nitrogen (N) supply are the two main factors limiting crops productivity. However, physiological mechanisms of crop responses to water and nitrogen stress remain to be elucidated. We examined stomatal conductance (gs), water use (ET), yield, and water productivity (WPc) of maize and analyzed the relationships between gs with ET, growth and yield under three growth stage-based deficit irrigation (mild, moderate and severe) and two nitrogen supplies (high and low nitrogen). Drought reduced gs as exacerbated by nitrogen stress. Coordination of gs by soil water content (SWC) and vapor pressure deficit (VPD) was affected by nitrogen supply. Controlling of transpiration by stomata was intensified by nitrogen stress in drought conditions. Yield was indirectly driven by gs through ET and aboveground biomass and directly by harvest index, but excessive water consumption did not result in higher yield instead reduced WPc. Field management optimization based on gs can promote the efficient use of water and fertilizer and the sustainable development of agriculture.

The Internet of Things (IOT) in Smart Agriculture Monitoring

Regardless of how the public perceives agriculture, the reality is that today's agriculture industry is more data-driven, precise, and sophisticated than ever before. The rapid rise of Internet-of-Things (IoT)-based technologies has transformed practically every industry, including "smart agriculture," which has moved away from statistical to quantitative techniques. Smart agriculture allows for more efficient fertilizer use and less water waste. The goal of the smart agribusiness research is to create a dynamic and emotionally supportive farm management network. IoT is being used in agriculture to learn about the agricultural field by using sensors for field monitoring and control. Sensors are used to acquire a better understanding of the crop field for monitoring, field control, and other applications. We'll look at how Internet of Things architectures aid farm fields in this research. The entire Internet of Things (IoT) Solicitations in Agriculture, as well as how they work, are provided. According to the report, IoT can also be used to fill in gaps in agriculture. Technology scalability should be encouraged without jeopardizing existing infrastructures functionality. The current state of Internet of Things (IoT) solicitations in agricultural, as well as future projections, are discussed in this article.

Exploring the relationship between plot size and fertilizer use efficiency: evidence from large-scale farming in China

PurposeThis paper investigates the relationship between plot size and fertilizer use efficiency (FE) in Chinese large-scale farming and searches for the underlying mechanisms that explain this relationship.Design/methodology/approachBased on a household- and plot-level data set of large-scale production units (LSPUs) from Jiangsu and Jiangxi Provinces, the technical and fertilizer use efficiency of large-scale rice production is estimated by applying a translog stochastic frontier production function. The authors impose a monotonicity condition on the translog frontier using a three-step procedure to get theoretically consistent efficiency estimates. A beta regression model is then used to explore the association between plot size and LSPUs' efficiency in fertilizer application.FindingsThe average FE for the sampled plots is around 30%, which shows a large potential for LSPUs to reduce fertilizer use. A U-shaped relationship is observed between plot size and FE. The authors relate this non-linear pattern to the substitution of labour with capital-intensive technology and the efficiency differences in terms of farming performance between family and hired workers.Originality/valueFirst, according to the authors’ knowledge, this paper is a first attempt to study the size–efficiency relationship focussing on fertilization practices of large-scale farming. The second contribution lies in the large-scale ranges of the plot-level data set. Third, efforts are made to reveal the mechanisms determining the plot size–FE relationship. Fourth, the authors provide guiding evidence for policymaking, as they show that the size of individual plots deserves equal attention in land consolidation decisions. Methodologically, this paper improves existing estimates of single-factor technical efficiency issued from a restricted production frontier model.

Is the Two-Line Hybrid Rice a Hindrance to the Efficient Use of Nitrogen Fertilizer in China?

Two-line hybrid rice (2LH) is accompanied by more nitrogen (N) input. To explore the difference in response of two-line and three-line hybrid rice (3LH) to N application, a three-year split-plot experiment was conducted. Three 2LHs and three 3LHs were set as main plots, and four N rates including 0 kg ha−1 (N0), 90 kg ha−1 (N90), 150 kg ha−1 (N150), and 210 kg ha−1 (N210) were set as subplots. 3LH had more panicles and yielded 7.95%, 6.31%, and 5.48% higher than 2LH in N0, N90, and N150, respectively. 2LH had a greater panicle weight in N210 and yielded 1.45% higher than 3LH. Leaf area index (LAI) had the greatest effect on the yields of both 2LH and 3LH, while the contribution of light extinction coefficient (K) was 46.35% and 12.80% those of LAI, respectively. The LAI, K, and radiation interception rate (RIR) of 2LH were smaller than those of 3LH in N0 and N90. The K of 2LH increased significantly as the N rate increased from 150 kg ha−1 to 210 kg ha−1, while that of 3LH showed no significant change, making the maximum RIR of 2LH greater than that of 3LH. 2LH, which intercepted more radiation through greater leaf extension to achieve higher yields, was able to use nitrogen fertilizer efficiently under a high N rate in China.

Valorisation of phyto-biochars as slow release micronutrients and sulphur carrier for agriculture

ABSTRACT Slow release micronutrients and sulphur sources are required for higher use efficiency of fertilizers in agriculture. The present investigation was undertaken to examine the salt soluble, desorbed and specifically sorbed fractions of micronutrients and sulphur in nutrient enriched phyto-biochars incubated at 15, 25 and 35°C for 48 h after pyrolysis of Lantana sp., Pinus sp. needles and wheat straw at 300 and 450 °C. The highest salt soluble fractions of Zn, Cu, Fe, Mn and B were recorded with pine needle biochar pyrolyzed at 300 °C, whereas that of S with lantana biochar pyrolyzed at 300 °C. The highest desorbed contents of Zn, Cu and Mn were with pine needle biochar (300 °C) and that of B and S with wheat straw biochar (450 °C) and lantana biochar (300 °C), respectively. An increase in incubation temperature from 15 to 25 °C increased the salt soluble contents of Zn and specifically sorbed contents of Fe and B but decreased salt soluble contents of Fe and B and desorbed amount of S significantly. Further, increase in incubation temperature from 25 to 35 °C significantly decreased the salt soluble contents of all nutrients except Mn and desorbed amount of S but increased specifically sorbed amount of Fe, B and S. Considering the salt soluble and desorbed contents of nutrients in enriched phyto-biochars, especially pine needle biochar pyrolyzed at 300 °C and treated with marginal or deficient nutrients for 2 d at 15–25 °C appeared to be suitable as a slow release fertilizer.

Productivity and profitability of tomato (Solanum lycopersicum) under drip fertigation and emitter types

A field experiment was conducted during winter 2014 and 2015 in Jagatsinghpur district of Odisha to study the effect of different fertigation levels and emitter types on productivity, input use efficiency and profitability of tomato (Solanum lycopersicum L.). The three levels fertigation, i.e. recommended dose (125-75-100 kg N-P2O5-K2O/ha) of fertiliser (RDF), 80% RDF and 60% RDF and four types of emitters, viz. online pressure compensating, online nonpressure compensating, inline pressure compensating and inline non-pressure compensating drippers were tested in split-plot design with three replications. Water soluble fertilisers, viz. urea, urea phosphate with sulphate of potash and sulphate of potash were used for fertigation. The maximum fruit yield of 59.8 t/ha, water-use efficiency of 21.17 kg/m3 water, benefit:cost ratio of 3.75 and internal rate of return of 62.16% and the minimum payback period of 2.26 years were recorded in fertigation with 100% RDF through online pressure compensating emitters. Fertiliseruse efficiency increased with decrease in fertigation level and the maximum value of 270.1 kg fruit/kg of NPK was recorded with 60% RDF through online pc emitters.

Effect of direct and residual sewage-sludge application on physiological attributes of rice-wheat cropping system

An experiment was conducted to assess the growth and yield attribute of rice–wheat cropping system (RWCS) as influenced by conjoint application of treated sewage sludge (TSS) and fertilizer at Agricultural Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India, from June 2017 to May 2019. The treatments comprised:  control, 100% RDF recommended dose of nitrogen (N), phosphorus (P) and potassium (K), 100% RDF + 20 t ha-1 TSS, 100% RDF + 30 t ha-1 TSS, 50% RDF + 20 t ha-1 TSS, 60% RDF + 20 t ha-1 TSS, 70% RDF + 20 t ha-1 TSS, 50% RDF + 30 t ha-1 TSS, 60% RDF + 30 t ha-1 TSS, 70% RDF + 30 t ha-1 TSS. The experiment was laid-out in randomized block design with three replications. The result of our study indicated that higher growth parameter (plant height, greenness index and tillers), yield attribute (length of panicle/ear, grain par panicle/ear) and yield of rice and wheat were recorded under 100% RDF with 20 and 30 t SS ha-1 as compared to 100% RDF alone. However, 70% RDF+ 30 t SS ha-1 had given equivalent or higher yield than 100% RDF in RWCS. Our results suggested that in short term application of sewage sludge would provide higher yield without any harmful/negative impact on environment. On the other hand, if the goal is efficient and economic use of fertilizer with greater sustainability, use as of 70% RDF with 20 and 30 t ha-1 SS as organic amendment can be recommend.

Foliar Application with Iron Oxide Nanomaterials Stimulate Nitrogen Fixation, Yield, and Nutritional Quality of Soybean.

Sustainable strategies for the management of iron deficiency in agriculture are warranted because of the low use efficiency of commercial iron fertilizer, which confounds global food security and induces negative environmental consequences. The impact of foliar application of differently sized γ-Fe2O3 nanomaterials (NMs, 4-15, 8-30, and 40-215 nm) on the growth and physiology of soybean seedlings was investigated at different concentrations (10-100 mg/L). Importantly, the beneficial effects on soybean were size- and concentration-dependent. Foliar application with the smallest size γ-Fe2O3 NMs (S-Fe2O3 NMs, 4-15 nm, 30 mg/L) yielded the greatest growth promotion, significantly increasing the shoot and nodule biomass by 55.4 and 99.0%, respectively, which is 2.0- and 2.6-fold greater than the commercially available iron fertilizer (EDTA-Fe) with equivalent molar Fe. In addition, S-Fe2O3 NMs significantly enhanced soybean nitrogen fixation by 13.2% beyond that of EDTA-Fe. Mechanistically, transcriptomic and metabolomic analyses revealed that (1) S-Fe2O3 NMs increased carbon assimilation in nodules to supply more energy for nitrogen fixation; (2) S-Fe2O3 NMs activated the antioxidative system in nodules, with subsequent elimination of excess reactive oxygen species; (3) S-Fe2O3 NMs up-regulated the synthesis of cytokinin and down-regulated ethylene and jasmonic acid content in nodules, promoting nodule development and delaying nodule senescence. S-Fe2O3 NMs also improved 13.7% of the soybean yield and promoted the nutritional quality (e.g., free amino acid content) of the seeds as compared with EDTA-Fe with an equivalent Fe dose. Our findings demonstrate the significant potential of γ-Fe2O3 NMs as a high-efficiency and sustainable crop fertilizer strategy.

Impacts of Slow-Release Nitrogen Fertilizer Rates on the Morpho-Physiological Traits, Yield, and Nitrogen Use Efficiency of Rice under Different Water Regimes

The efficient use of water and fertilizer is vital for optimizing plant growth and yield in rice production. To achieve sustainable rice production and resource management, the ways in which applied water and nitrogen affect the root and shoot morpho-physiology, as well as yield, must be understood. In this study, a pot experiment was conducted to investigate the effects of slow-release nitrogen fertilizer (sulfur-coated urea) application at three levels (light nitrogen (NL), medium nitrogen (NM), and heavy nitrogen (NH)) on the growth, yield, and nitrogen use efficiency (NUE) of rice grown under three water regimes (wetting and soil saturation (WSS), wetting and moderate drying (WMD) and wetting and severe drying (WSD)). The results revealed that differences in water regimes and fertilizer rates led to significant differences in the roots, shoots, yield, and NUE of rice. Increasing the N dosage by 5% enhanced the root and biomass production by 16% in comparison with that of the other groups. The NH×WSS treatment produced the greatest root length, weight, density, active absorption, and oxidation. However, the integration of WSS × NL generated the maximum value of nitrogen apparent recovery efficiency (63.1% to 67.6%) and the greatest value of nitrogen partial factor productivity (39.9 g g−1 to 41.13 g g−1). Transmission electron microscopy (TEM) images showed that plants grown under high and medium nitrogen fertilizer rates with WSS had improved leaf mesophyll structure with normal starch grains, clear cell walls, and well-developed chloroplasts with tidy and well-arranged thylakoids. These results show that TEM images are useful for characterizing the nitrogen and water status of leaves in the sub-micrometer range and providing specific information regarding the leaf microstructure. The findings of this study suggest that the application of NH×WSS can produce improvements in growth traits and increase rice yield; however, the NL×WSS treatment led to greater NUE, and the authors recommend its usage in rice agriculture.

Economic and sustainability benefits of the United States Golf Association's investment in water, fertilizer, and pesticide management research

AbstractThe United States Golf Association (USGA) has invested more than US$45 million in turfgrass and environmental research since 1983. This effort has developed research‐based management practices that have contributed to the efficient use of water, fertilizer, and pesticides on U.S. golf courses. Still, there is insufficient evidence of the economic benefits. Therefore, our objective was to estimate the golf industry's resource and economic benefits from the USGA's investment in water, fertilizer, and pesticide management research. Data were collected from an online survey focused on the benefits associated with golf facilities’ adoption of research‐based management practices in six primary areas of interest: (a) evapotranspiration‐based irrigation scheduling (water budgeting), (b) soil moisture sensing, (c) best management practices that reduce nonpoint source pollution by fertilizers and pesticides, (d) putting green construction techniques, (e) naturalized roughs, and (f) improved turfgrass cultivars. Only the first three areas are discussed in this study. Based on data from the survey, multiple econometric models were developed for each of the management practices. All three research‐based management practices have been widely adopted throughout the U.S. golf industry. Across the three management practices studied, modeling indicated a total annual financial benefit of US$1.03 billion to the golf industry. This compares with an estimated yearly Green Section budget of roughly US$10 million, of which US$2 million is for turfgrass and environmental research. Research investment by governments and industry leaders is critical to the sustainability of the golf industry.

The relationship between farm size and fertilizer use efficiency: Evidence from China

Low fertilizer use efficiency is commonly found in China's agriculture sector. It is critical to understand the drivers of fertilizer use in order to increase fertilizer use efficiency (FUE). The purpose of this paper is to investigate the relationship between farm size and FUE based on farm-level data in China. The results suggest a positive farm size–FUE relationship. The estimated elasticities of farm size for rice, maize, wheat–maize, and rice–maize are similar, and the average elasticity of farm size is around 0.2. Statistically, a 1% increase in farm size is associated with a 0.2% increase in FUE. The positive effect of farm size on FUE is not due to the increase in yield, but the reduction in fertilizer use while keeping yield largely unchanged. The findings suggest that promoting the expansion of farm size may increase FUE, and thus reduce environmental pollution caused by fertilizer overuse.

Sources of terrestrial nitrogen and phosphorus mobilization in South and South East Asian coastal ecosystems

South and Southeast Asia (SSEA) is a socially, economically and ecologically diverse region, with a rapidly growing population and accelerating industrial development, agricultural intensification using manufactured fertilizers, terrestrial landscape change, expansion of water engineering, sewage production and land conversions. Nitrogen and phosphorus are major nutrients that play an essential role in the eutrophication of inland and coastal water bodies. Eutrophic areas, when combined with appropriate coastal ocean physical conditions, can develop into hypoxic zones that result in long-term ecosystem disruption. This study addressed changes in terrestrial nitrogen and phosphorus mobilization associated with land-use transitions, fertilizer use and sewage from 2002 to 2016 in the SSEA region, with a focus on the Mekong and Krishna-Godavari watersheds. Terrestrial mobilization results from the internal production or addition of reactive, soluble and/or plant available forms of nitrogen and phosphorus. To estimate terrestrial mobilization associated with land conversion, published data were mined for estimates of land cover change effects on soil carbon, nitrogen and phosphorus pools. Data on exogenous fertilizer and sewage effluents were also compiled from the literature. From the analysis, it showed that fertilizer input was the largest source of nitrogen and phosphorus in both case study watersheds. Sewage and land conversion were not a significant source of terrestrial phosphorus mobilization in either watershed. All land conversions resulted in declines in soil carbon, ranging from 11% to 38%. Nitrogen increased, on average by 15%, in conversions of agricultural to urban land, but decreased in all other conversions. Phosphorus increased by 89% in wetland to agriculture conversions, but decreased between 2% and 24% for other land conversions. Expansion of agriculture at the expense of forest was the dominant land conversion in the Mekong watershed. Urbanization, at the expense of agriculture and forest, was the dominant land conversion in the Krishna/Godavari watershed. These results suggest that management of nutrient pollution (N and P) in SSEA will need to focus on reducing the use and/or improving the efficiency of fertilizer use along with regular consolidated monitoring in both watersheds.

Response of Fertilizer Levels and Safflower Varieties to Growth, Yield and Economics of Safflower under Irrigated Condition

Considering the nutrient use efficiency of fertilizers under irrigation condition, a field studies were conducted during rabi 2016 on a clay loam soil at the PGI farm, MPKV, Rahuri, to study the influence of fertilizer levels and different varieties of safflower. The fertilizer dose of 100% recommended dose of fertilizer with variety SSF 748 is beneficial for maximum seed yield (2766.46 kg ha-1), net monetary returns (Rs. 45054.0 ha-1) and benefit cost ratio (2.54) of safflower.

Sustainable Utilization of Sewage Sludge through the Synthesis of Liquid Fertilizer

In a world with a growing human population, resources are becoming increasingly scarce. To ensure food supply, fertilizers are often used to accelerate growth when planting agricultural products. Sewage sludge (SS), containing as high as 10–15 wt% Phosphorus (P), can be synthesized into liquid fertilizer. P species in SS can generally be classified into four types: inorganic phosphorus (IP), organic phosphorus (OP), nonapatite inorganic phosphorus (NAIP), and apatite phosphorus (AP). However, OP is not leached out by wet chemical methods and NAIP is not bioavailable. This study investigated the P-form conversion (OP and NAIP to AP) in SS by adding 8 wt% CaO at 300 °C. SS through pretreatment can easily leach out P when combined with organic acid. The content of heavy metals is in accordance with fertilizer regulations in a leaching solution. The solution was mixed with potassium and ammonia compounds to synthesize a liquid fertilizer. To ensure the safe and efficient use of liquid fertilizer and undertake an analysis of heavy metals, an aquatic organisms (D. magna) toxicity test, and the growth of plants test were both used. The liquid fertilizer can be demonstrated to accelerate the growth of plants while not causing the death of D. magna in short time, as the liquid fertilizer has enough nutrients to help the D. magna to survive.

Phosphorus biofortification and uptake in maize enhanced with integrated phosphorus management

A limited phosphorus (P) supply restricts crop growth, productivity and seed setting in various crops. Adequate P enhances early maturity and crop quality with a big yield. A consequential two-year (2016–2017 and 2017–2018) field experiment was conducted to determine the effect of peach residues, compost and biochar, three P levels (50, 75 and 100 kg ha−1) and two beneficial microbes (PSB and Trichoderma) on P biofortification in maize and P fertilizer use efficiency (FUE). Experiential findings revealed that among the organic sources, peach biochar was the most promising source for the highest P uptake and bio-fortification. Among the beneficial microbes, soil application of Trichoderma showed extremity for higher grain P content, grain P uptake (GPU) and fertilizer use efficiency (FUE), while seed inoculation with PSB produced higher leaf P content, stalk P content, stover P content, stalk P uptake (SPU) and total P uptake (TPU) respectively. Inorganic P fertilization under 100 kg ha−1 enhanced grain P content, leaf P content, stalk P content, stover P contents, GPU, SPU and TPU, although the highest FUE was recorded under the lowest P rate (50 kg ha−1). Conclusively, it could be recommended that to get maize higher yield and enhance P uptake and bio-fortification, soil application of Trichoderma with peach biochar and 100 kg P ha−1 should be treated under P deficient soil.

Irrigation with Activated Water Promotes Root Growth and Improves Water Use of Winter Wheat

Magnetic or oxidation treatment of irrigation water can promote the transport of water and nutrients by the root system, improve the efficiency of water and fertilizer use and potentially increase yields. Hydroponic and field experiments were conducted to explore how irrigation with magnetized and/or oxidized water affects grain yield and water-use efficiency (WUE) in winter wheat with an emphasis on physiological changes in the root system. Hydroponic cultivation of winter wheat with pure groundwater and brackish water included the following treatments: control group (CK−G, CK−B); magnetization (GM, BM); oxidation (GO, BO); and the combination of magnetization and oxidation (G(M+O), B(M+O), G(O+M), B(O+M)). Field experiments only tested irrigation with various types of groundwater, including the control group (IG), magnetization treatment (IGM), oxidation treatment (IGO), and the combination of the two treatment methods (IG(M+O), IG(O+M)). Hydroponic cultivation revealed that the magnetic treatment and oxidation of both groundwater and brackish water can significantly improve the root vigor of winter wheat, i.e., improvements of 100.5–253.7% and 100.4–213.9% were seen in the groundwater and brackish treatment groups, respectively, relative to the control group. The root length density (RLD) of wheat increased by 67.6% (GM), 79.4% (GO), 7.5% (BM), and 40.0% (BO) relative to the respective control groups (CK−G and CK−B). Moreover, the root weight density (RWD) for BO and B(O+M) treatments improved significantly (66.7% and 55.4%, respectively) relative to CK−B. The maximal increases in root surface area density (RSD) were observed in treatments GO and B(O+M), which showed values 125% and 100%, respectively, higher than what was measured for the control groups. The root/shoot ratios of the GO and G(O+M) treatments improved significantly (by 75.3% and 62.0%, respectively) relative to CK−G. The results of field experiments showed that wheat in the IGO and IG(O+M) plots absorbed more water from the soil than wheat in the of IG plots (increases of 13.9% and 16.9%, respectively). Furthermore, the IGO and IG(O+M) treatments produced significantly higher grain yields and WUE than the IG plots, with IGO producing the maximum yield (11.7 × 103 kg ha−1) and IG(O+M) the highest observed WUE (30.3 kg ha−1 mm−1). Hence, the research provides clear evidence that the irrigation of winter wheat with magnetized and/or oxidized water can increase grain yields and WUE.

English

An experiment was conducted on farmer's fields during the main cropping season of 2016/2017 in Adiyo district, Southwestern Ethiopia to optimize fertilizer rate recommendation for major cereal production systems by using bread wheat (Triticum aestivum L.) as test crop. Experiment was laid out in a randomized complete block design (RCBD) with three replications for sixteen treatments. The grain yield and yield components were all elevated remarkably by applying different rates and types of fertilizers; five levels of N (0, 23, 46, 69 and 92 kg ha-1); four levels of P (0, 10, 20 and 30 kg ha-1); and four levels of K (0, 10, 20 and 30 kg ha-1). In addition, the last three diagnostic treatment foliar applications 45 days after planting and compared with control (absolute zero) treatment was done. Yield and yield components were measured using the SAS statistical package program version 9.3. The least significant difference (LSD) at 5% probability level was used to establish the difference among the means. To investigate the economic feasibility of the fertilizers, partial budget, dominance analysis and marginal rate of return were used. There was significant difference in grain yield and yield components of bread wheat (danda‘a variety) among the treatments. As the results showed high biological yield response recorded under 92N20P20K kg ha-1 (5.62 t ha-1) and the lower yield response was under control treatment (4.09 t ha-1); but high economic yield response recorded under 23N20P kg ha-1 (5.20 t ha-1). In conclusion, the fertilizers containing nutrient rate of 23N20P (kg ha-1) had brought the higher economic net benefit (27409.99 ETB/ha) with MRR (92.61%) and showed efficient use of fertilizer. Therefore, based on the biological yield response and economic net benefit, it is recommended to apply 23N20P (kg ha-1) fertilizers at Adiyo district, Southwestern Ethiopia and areas with the same soil conditions and agro-ecology. Key words: Economic analysis, foliar application, wheat yield, nutrient type, rate.

Nano agrochemical zinc oxide influences microbial activity, carbon, and nitrogen cycling of applied manures in the soil-plant system

The widespread use of nano-enabled agrochemicals in agriculture for remediating soil and improving nutrient use efficiency of organic and chemical fertilizers is increasing continuously with limited understanding on their potential risks. Recent studies suggested that nanoparticles (NPs) are harmful to soil organisms and their stimulated nutrient cycling in agriculture. However, their toxic effects under natural input farming systems are just at its infancy. Here, we aimed to examine the harmful effects of nano-agrochemical zinc oxide (ZnONPs) to poultry (PM) and farmyard manure (FYM) C and N cycling in soil-plant systems. These manures enhanced microbial counts, CO2 emission, N mineralization, spinach yield and N recovery than control (unfertilized). Soil applied ZnONPs increased labile Zn in microbial biomass, conferring its consumption and thereby reduced the colony-forming bacterial and fungal units. Such effects resulted in decreasing CO2 emitted from PM and FYM by 39 and 43%, respectively. Further, mineralization of organic N was reduced from FYM by 32%, and PM by 26%. This process has considerably decreased the soil mineral N content from both manure types and thereby spinach yield and plant N recoveries. In the ZnONPs amended soil, only about 23% of the applied total N from FYM and 31% from PM was ended up in plants, whereas the respective fractions in the absence of ZnONPs were 33 and 53%. Hence, toxicity of ZnONPs should be taken into account when recommending its use in agriculture for enhancing nutrient utilization efficiency of fertilizers or soil remediation purposes.

Pengelolaan Tanaman Penutup Tanah untuk Meningkatkan Produksi Jagung Manis Di Lahan Kering Vertisol Lombok

One of the obstacles in increasing maize production in Indonesia is the low efficiency of fertilizer use by plants as a result of low levels of organic matter in the soil. Although it only occupies a portion of approximately 2-10%, the role played by organic matter in the soil is very large, both in physical, chemical and biological aspects. One of the practical and efficient alternatives to increase organic matter in the soil is through the management of cover crops (TPT). In this study, individually or after being combined into one, three types of TPT were stocked before the harvest of the predecessor plant (rice). As a comparison, plots without TPT were also provided. Rice litter together with TPT biomass from each TPT treatment was returned to the soil after rice was harvested in a separate plot pattern. In each TPT treatment plot, fertilization treatments were made with a dose of 0 kg/ha NPK, 100 kg/ha NPK, 200 kg/ha NPK and 300 kg/ha NPK. The experimental results showed that TPT biomass had a positive impact on increasing the growth and yield of sweet corn on vertisol soils. Provision of cover crops in the form of a mixture of cowpea, mung bean and krotalaria tended to have a better effect than individual administration. From the results of this experiment, it is also known that the provision of precursor plant biomass combined with TPT biomass can reduce the use of chemical fertilizers by 50-60% of the maximum plant requirement.

Effects of irrigation and fertilization on grain yield, water and nitrogen dynamics and their use efficiency of spring wheat farmland in an arid agricultural watershed of Northwest China

Inappropriate irrigation and nitrogen application had caused low water and nitrogen use efficiency and severe NO3--N leaching in spring wheat field in the Wuliangshuhai lake watershed (WLSLW) of Northwest China. Thus, aimed at determining the rational irrigation and nitrogen fertilization for spring wheat in this area, field experiments were carried out in the 2019 and 2020 seasons to investigate the effects of irrigation and nitrogen application on soil water and nitrogen status, grain yield, and water and nitrogen use efficiency. Three irrigation levels, i.e., 180, 315, and 450 mm (I3, I2 and I1), and three nitrogen fertilization rates, i.e., 170, 250, and 340 kg N ha−1 (N3, N2 and N1) were respectively considered in the experiments. Results indicated that increasing irrigation depth increased root zone soil available water, and increasing nitrogen application could significantly enhance the available nitrogen content in root zone soils and the soil water utilization amount by wheat. Under the control treatment (I1N1), about 25–32% of the applied nitrogen was leached out of the root zone soils throughout the year. Compared to the control treatment, the I2N2 treatment could reduce NO3--N leaching by 32%, and increased the water use efficiency (WUE) and partial factor productivity of nitrogen fertilizer (PFPn) by 33% and 44%, respectively. In addition, the highest yield and net profit of 8078 kg ha−1 and 1.82×104 Chinese Yuan ha−1 was achieved by the I2N2 treatment, respectively, and it was 6% higher than that of the control treatment. Therefore, considering the grain yield, WUE, PFPn, economic benefits and environmental impacts, the strategy of 315 mm irrigation and 250 kg N ha−1 nitrogen application is recommended for spring wheat in the arid agricultural watershed of Northwest China and areas with similar conditions.