Increased Maize Yield Research Articles

Influence of biological fertilizer and plant cover in the physical properties of soil

As propriedades físicas do solo exercem influencia no crescimento radicular das plantas, que dependendo do nível de restrição, a produtividade da cultura é reduzida. O objetivo deste estudo foi verificar os efeitos da adubação biológica e plantas de cobertura sobre as propriedades físicas do solo. O estudo foi desenvolvido em duas safras (2015/16 e 2016/17), onde o delineamento experimental foi em blocos casualizados em esquema fatorial duplo: adubo biológico (com e sem) e condições de cobertura vegetal do solo (milheto, crotalária e pousio limpo), e um fragmento de floresta como testemunha. A adubação biológica e as plantas de cobertura do solo promoveram incrementos significativos na umidade do solo, macroporosidade e porosidade total, além de reduzir a microporosidade e a resistência do solo a penetração. Deste modo, as propriedades físicas do solo foram incrementadas com o uso de adubo biológico, milheto e crotalária como cobertura do solo. O adubo biológico não promoveu incrementos de produtividade da soja e do milho, entretanto, estas apresentaram incrementos significativos com o uso de milheto e crotalária.

Effect of Organic Fertilizer and Inorganic Fertilizer Application on N2O Emissions from Fluvo-aquic Soil in the North China Plain

The North China Plain is an important grain production area in China. Due to the low content of soil organic carbon, increasing the application rate of nitrogen fertilizer would not lead to a continuous increase of maize yield at present. The combined application of organic fertilizer and inorganic fertilizer is widely regarded as a measure to simultaneously increase grain yield and soil organic carbon; however, the effect of organic fertilizer and inorganic fertilizer application on N2O emissions from farmland in the North China Plain is unclear. Here, N2O emissions and crop yields in cropland under the combined application of different types and rates of organic fertilizers plus inorganic N fertilizer were measured in the North China Plain. The field experiment included eight treatments:no N fertilizer (CK), inorganic fertilizer (NPK), 40% cow manure N plus 60% inorganic fertilizer N (CM), 40% chicken manure N plus 60% inorganic fertilizer N (FC), 40% pig manure N plus 60% inorganic fertilizer N (FP), 20% cow manure N plus 80% inorganic fertilizer N (1/2CM), 20% chicken manure N plus 80% inorganic fertilizer N (1/2FC), and 20% pig manure N plus 80% inorganic fertilizer N (1/2FP). The N2O fluxes were significantly correlated with soil water-filled pore space during the maize season (P<0.05). There was a significant linear relationship between N2O fluxes and soil dissolved organic carbon content during the maize season in all treatments except the NPK treatment. In the maize season, N2O emission was 0.50 kg·hm-2 under CK treatment, and increased to 2.28 kg·hm-2 under NPK treatment. However, when the proportion of manure N to total N applied was reduced from 40% to 20%, N2O emissions were significantly reduced by 33.6%, 43.7%, and 12.1% under 1/2CM, 1/2FC, and 1/2FP treatments, respectively. The difference in application rate of organic manure N did not significantly affect maize yield. The reduction of N2O emission at the low manure application rate compared with the high manure application rate was likely due to the decrease in dissolved organic carbon in soils.

Multivariate Tools for Evaluating the Use of Organic Fertilizers on Soil Microbial Properties and Maize Yield

The global demand for protein led to the increase of animal production in the world and, mainly, in Brazil. As a consequence, there was an increase in the amount of waste produced, and the need to seek alternatives for its sustainable use. Microbial indicators and multivariate tools can assist in the proper measurement of the impact of the use of this waste on the soil. This study aimed to: 1) measure the effect of the application of organic fertilizers of animal origin in the no-tillage system on soil microbial attributes and its relationship with maize yield; 2) evaluate the potential of separation/discrimination of the different sources of organic fertilizers based on yield and soil microbial and chemical-physical attributes, using multivariate tools. Treatments consisted of annual application of: poultry manure (PM), liquid swine manure (LSM), poultry manure compost (PMC), swine manure compost (SMC), cattle manure compost (CMC) and control (C), without fertilization. Organic fertilizers promoted higher values of microbial biomass (MB) and MBC:TOC ratio in treatments CMC, SMC and PM in the first sampling season (E1), followed by PM, LSM and PMC in the second sampling period (E2). The data show that PM promoted microbial growth in both seasons, with higher metabolic efficiency increasing maize yield by 30% in relation to the treatment with the second highest production, PMC. Multivariate analysis techniques prove to be important tools to study soil quality indicators in systems which use organic fertilizers.

Yield effects of climate-smart agriculture aid investment in southern Malawi

Binding resource constraints in many low- and middle-income countries aggravate food insecurity risk in the face of climate change. To help mitigate such risk and increase food security, international development agencies have invested billions of dollars in climate-smart agriculture (CSA) programs over the past decade. However, rigorous evidence on the food security impacts of CSA aid through crop yields remains scant generally, and specifically in sub-Saharan Africa. Most studies have not explicitly linked CSA adoption and yield impacts with CSA aid interventions among smallholder farmers. Here, we respond to this knowledge gap by estimating the impact of a major CSA aid effort (the United States Agency for International Development-funded Wellness and Agriculture for Life’s Advancement (WALA) project) on agricultural yields in Southern Malawi. Based on primary survey data from a sample of 808 households in the project area, we use endogenous switching regression and a control function approach to estimate CSA adoption and impacts on maize yield in 2016, controlling for potential program placement bias, selection bias in CSA adoption, and endogeneity issues. We found a 53% increase in maize yield among CSA adopters in the drought year of 2016. Results demonstrate that policies and funding streams supporting CSA in low-income, dryland contexts such as southern Malawi can have important impacts on food security by boosting crop yields in the face of increasing climate uncertainty and extreme weather shocks.

Designing high-yielding maize ideotypes to adapt changing climate in the North China Plain

Global food production to meet growing demand is facing serious challenges from changing climate. Efficient adaptation is an important approach for mitigating the effects of changing climate on crop production and secure food supply in the future. Maize is a critically important source of food, feed and fuel, and is highly vulnerable to warming climate. In our study, using Agricultural Production Systems sIMulator (APSIM) model, we designed different features of maize ideotypes sown at various times to maximize the yield and water use efficiency (WUE) under future climate conditions in the North China Plain (NCP). The future climate projections were sourced from one Global Climate Model (GCM) from the Coupled Model Inter-comparison Project phase 6 (CMIP6) under a high emission scenario of future societal development pathway (SSP) 585. The selected GCM projected future mean maximum (minimum) temperature during maize growing season to increase by 1.9 °C and 3.7 °C (1.5 °C and 3.2 °C) in 2040s (2031–2060) and 2080s (2071–2100) respectively, compared to the baseline (1981–2010). The mean solar radiation during maize growing season increased by 3.9% and 6.5%, and total precipitation rose by 17.3% and 21% in 2040s and 2080s, respectively. Our simulated results indicated future maize yield without adaptation decreased slightly by 2.3% in 2040s and 2.4% in 2080s, but WUE significantly increased by 11.8% and 26.6% in 2040s and 2080s, respectively. We found that delayed sowing date was able to increase maize yield and WUE under the future climate conditions. When the ideotypic cultivar and optimum sowing date were adopted, simulated yield increased by 132% and 124% in 2040s and 2080s, respectively, and WUE rose by 85% and 117%, respectively. Our simulated results indicate maize ideotypes under future climate should have a longer reproductive growing period, faster potential grain filling rate, larger maximum grain numbers and larger radiation use efficiency. Maize ideotypes based on simulated results from APSIM models could provide breeders and/or plant scientists with a road map to choose the ideal target traits for increasing maize production and adapting future climate.

Soil Application of Zinc Fertilizer Increases Maize Yield by Enhancing the Kernel Number and Kernel Weight of Inferior Grains.

Improving the development of inferior grains is important for increasing maize yield under high-density conditions. However, the effect of micronutrients, especially zinc (Zn), on the development of inferior grains and maize yield under field conditions has not been evaluated to date. A field experiment with six Zn application rates (0, 2.3, 5.7, 11.4, 22.7, and 34.1 kg/ha) was conducted to investigate the effects of soil application of Zn fertilizer on the development of inferior grains. Pollen viability was measured at the tasseling stage. The maize spike was divided into apical (inferior grain), middle, and basal sections for further measurement at harvest. Results showed that soil application of Zn fertilizer increased maize yield by 4.2–16.7% due to increased kernel number and weight in the apical, but not in the middle and basal sections. Zn application also significantly increased pollen viability at the tasseling stage. The critical Zn concentrations in shoots at the tasseling stage for obtaining high pollen viability and high kernel numbers of inferior grains were 31.2 and 35.6 mg/kg, respectively. Zn application also increased the 1,000-kernel weight of inferior grain due to high biomass accumulation. Furthermore, the grain Zn concentration of inferior grain with Zn application increased by 24.3–74.9% compared with no Zn application. Thus, soil application of Zn fertilizer successfully increased grain yield of maize by improving pollen viability, kernel number, and kernel weight of inferior grains (apical section), also contributing to grain Zn biofortification.

Maize yield in smallholder agriculture system-An approach integrating socio-economic and crop management factors.

Yield gaps of maize (Zea mays L.) in the smallholder farms of eastern India are outcomes of a complex interplay of climatic variations, soil fertility gradients, socio-economic factors, and differential management intensities. Several machine learning approaches were used in this study to investigate the relative influences of multiple biophysical, socio-economic, and crop management features in determining maize yield variability using several machine learning approaches. Soil fertility status was assessed in 180 farms and paired with the surveyed data on maize yield, socio-economic conditions, and agronomic management. The C&RT relative variable importance plot identified farm size, total labor, soil factors, seed rate, fertilizer, and organic manure as influential factors. Among the three approaches compared for classifying maize yield, the artificial neural network (ANN) yielded the least (25%) misclassification on validation samples. The random forest partial dependence plots revealed a positive association between farm size and maize productivity. Nonlinear support vector machine boundary analysis for the eight top important variables revealed complex interactions underpinning maize yield response. Notably, farm size and total labor synergistically increased maize yield. Future research integrating these algorithms with empirical crop growth models and crop simulation models for ex-ante yield estimations could result in further improvement.

The effect of biochar, lime and ash on maize yield in a long-term field trial in a Ultisol in the humid tropics

A multi-season field trial was carried out to investigate the effect of the amendment of biochar, lime, ash and washed biochar on the growth of maize. A degraded, strongly acidic Ultisol (pHKCl 3.60), with a relatively high exchangeable aluminium content (2.4 cmolc/kg) and a low exchangeable calcium content (0.99 cmolc/kg), was used. Soil was treated once at the beginning of the field trial and crop growth was monitored over seven planting seasons (PS). All treatments increased maize yield. The average increases were; seven times for biochar, five times for lime, five times for washed biochar and eight times for ash treatment, when compared to the control across all PS. The effect of biochar, lime and ash treatments on maize yield were sustained over the seven PS. Soil pHKCl was significantly increased (p < 0.05 level) following the addition of all of the amendment materials. All treatments significantly reduced the concentration of Al3+ when compared to the control (p < 0.05), with the lowest concentrations for the lime and ash treatments. The ash treatment also increased the concentration of macronutrients (K, P and Mg) to the greatest extent. Results showed that there was a clear liming effect at play. The better performance of biochar compared to lime, despite lime having the highest pH and the lowest Al3+ concentration, can be explained by the additional K, Mg and P the biochar adds to the soil. Results also showed a clear nutrient addition effect where ash added the most nutrients. Overall, this work supports the fact that small scale farmers in Indonesia should produce biochar from their waste agricultural materials. Doing so not only provides an increase in crop productivity, but also sequesters carbon resulting in the best overall environmental benefit.

The impact of production shocks on maize markets in Ethiopia: implications for regional trade and food security

In this article, we demonstrated the dynamic impact of a bumper harvest and drought shocks on the maize market and on the trade regime in Ethiopia. Regional market integration of Ethiopia’s white maize market with the South Sudan and Kenyan maize markets was also examined using cointegration analysis. Despite the renewed conflict in South Sudan, Addis Ababa maize market is cointegrated with Juba’s maize market. The simulation analysis indicated that a 20% increase in maize yield could reduce the maize price by 81%. This implies a decrease in the maize price level of 70% (110 USD/t) below the export parity price. This makes maize exports profitable and shifts the trade regime from autarky to an export parity regime. On the other hand, the effect of a drought could increase maize prices by 61% in the short run (within the year). At the current market price, the domestic maize price is wandering between the border prices and it is unprofitable to export maize. Therefore, lifting the export ban, even during normal harvest seasons, would not do any harm to the domestic maize price.

The application potential of Trichoderma T-soybean containing 1-aminocyclopropane-1-carboxylate for maize production

The present work was carried out to investigate the application potential of Trichoderma harzianum T-soybean in maize (Zea mays) production. The effects of T-soybean metabolite on pathogen growth, maize growth and resistance response as well as 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCD) (EC 4.1.99.4) crude enzyme liquid on germination and seedlings growth of maize were analysed in greenhouse condition. The effects of bio-fertilizer containing T. harzianum T-soybean (BIOT) on maize production were also analysed by determining soil enzymes activities and soil microorganisms counts in field condition. The results suggested that T-soybean significantly inhibited growth of pathogenic Fusarium graminearum and induced resistance response of maize seedlings by increasing antioxidant enzyme activities including peroxidase (POD) (EC 1.11.1.6), polyphenol oxidase (PPO) (EC 1.10.3.2), phenylalanine ammonia-lyase (PAL) (EC 4.3.1.5) and β-1,3-glucanase (EC 3.2.1.39) in leaves. ACCD from T-soybean also was involved in the beneficial effect. Compared with only using chemical fertilizer, BIOT increased microorganism counts and activities of soil enzymes, and then reduced the incidence of maize stalk rot, and increased maize yield. In sum, T-soybean has potential values of applications in sustainable agriculture.

A Study on the Potential Fertilization Effects of Microgranule Fertilizer Based on the Protein and Calcined Bones in Maize Cultivation

In the presented manuscript, the method of production, mechanism of action and the potential fertilizing effect of fertilizer soil microgranules, characterized by a controlled release of ingredients, that were produced from thermally processed bone waste and protein were described. The prepared fertilizer was tested in 3 doses in a pot experiment and thereafter the selected dose of 30 kg ha−1 was utilized in field conditions. The applied dose of fertilizer caused an average increase of maize yield of 620 kg ha−1 (grain moisture 14%). It was found that the obtained increase of maize did not result from the amount of supplied micro and macro elements to the soil, but it was a consequence of the fertilizer’s mechanism of action. It was shown that the release of nitrogen in ammonium form from protein degradation due to the influence of fertilizer components and water had impact on the intensive growth and development of plant root system. This resulted in an increase in plant resistance to water stress during the growing season and consequently, greater yield. The developed soil fertilizer (produced mainly from the processed waste) with the proposed mechanism of action should be successfully applied in fertilizing plants that are grown in areas characterized by cyclical water shortages during the growing season

Enhancing root lodging resistance of maize with twin plants in wide-narrow rows: a case study

ABSTRACT Root lodging is known to reduce the yield and quality of maize, which will be more serious driven by the changes in agriculture such as the higher planting density and the more extreme precipitation events. Here we describe a new cultivation method to reduce the root lodging of maize. We designed two planting layouts: twin plants (TP) and single plant (SP) in a hole with the same density. The vertical root-pulling resistance, angle and rate of natural root lodging, root and shoot morphology related to root lodging and maize yield were compared between two planting layouts. TP planting significantly increased the vertical root-pulling resistance and angle of natural root lodging. This can be partly attributed to the gripping force between the staggered crown roots of the two adjacent plants. Moreover, the TP planting could increase root-lodging resistance by increasing the root angle (acute angle between the stem direction and root) and stem diameter. Additionally, TP planting did not reduce the maize yield and biomass. Consequently, our study demonstrated that the twin plants in a hole are effective to decrease the root lodging of maize in southwest of China. This technique is simple, inexpensive, safe, stable, and has broader potential for increasing maize yield and quality.

Influence of plastic film mulching and planting density on yield, leaf anatomy, and root characteristics of maize on the Loess Plateau

In rainfed areas of northwestern China, maize production is constrained mainly by low temperature during early growth and water limitation during the entire growth period. Plastic film mulching is commonly used to increase maize yield in this area, because it increases topsoil temperature and moisture content as well as water use efficiency. However, the physiological and anatomical bases of maize yield improvement with plastic film mulching are not well understood. The effects of plastic film mulching and planting density on maize yield, photosynthetic characteristics, respiration, leaf anatomy, and root growth were studied in a two-year field experiment conducted on the Loess Plateau of China in 2017 and 2018. The experiment used a split-split plot design with two mulching treatments (plastic film mulching and no mulching), two planting densities (7.5 × 104 and 10.5 × 104 plants ha−1), and two maize cultivars, Zhengdan 958 and Xianyu 335. Compared with no mulching, plastic film mulching increased maize yields by 31.1%–46.4% in 2017 and 3.6%–34.7% in 2018. Compared with low planting density, high planting density significantly increased and slightly reduced yields of both cultivars in the dry year 2017 and the rainy year 2018, respectively. Plastic film mulching increased photosynthesis and respiration as well as leaf stomatal density and aperture. Photosynthetic rate, dark respiration, and stomatal conductance and aperture were lower at high planting than at low planting density. Maize yield was positively correlated with photosynthesis, dark respiration, and stomatal aperture. Mulching increased root dry weight and length in the 0–20 cm soil layer and root activity at maturity. Overall, the changes in root growth and leaf anatomy resulted in increased photosynthesis and dark respiration, and the increased photosynthesis contributed to the increase in grain yield and biomass production under plastic film mulching conditions. Our results increase understanding of the physiological mechanisms by which plastic film mulching increases maize yield in water- and temperature-limited areas.

Science-based decision support for formulating crop fertilizer recommendations in sub-Saharan Africa

In sub-Saharan Africa, there is considerable spatial and temporal variability in relations between nutrient application and crop yield, due to varying inherent soil nutrients supply, soil moisture, crop management and germplasm. This variability affects fertilizer use efficiency and crop productivity. Therefore, development of decision systems that support formulation and delivery of site-specific fertilizer recommendations is important for increased crop yield and environmental protection. Nutrient Expert (NE) is a computer-based decision support system, which enables extension advisers to generate field- or area-specific fertilizer recommendations based on yield response to fertilizer and nutrient use efficiency. We calibrated NE for major maize agroecological zones in Nigeria, Ethiopia and Tanzania, with data generated from 735 on-farm nutrient omission trials conducted between 2015 and 2017. Between 2016 and 2018, 368 NE performance trials were conducted across the three countries in which recommendations generated with NE were evaluated relative to soil-test based recommendations, the current blanket fertilizer recommendations and a control with no fertilizer applied. Although maize yield response to fertilizer differed with geographic location; on average, maize yield response to nitrogen (N), phosphorus (P) and potassium (K) were respectively 2.4, 1.6 and 0.2 t ha−1 in Nigeria, 2.3, 0.9 and 0.2 t ha−1 in Ethiopia, and 1.5, 0.8 and 0.2 t ha−1 in Tanzania. Secondary and micronutrients increased maize yield only in specific areas in each country. Agronomic use efficiencies of N were 18, 22 and 13 kg grain kg−1 N, on average, in Nigeria, Ethiopia and Tanzania, respectively. In Nigeria, NE recommended lower amounts of P by 9 and 11 kg ha−1 and K by 24 and 38 kg ha−1 than soil-test based and regional fertilizer recommendations, respectively. Yet maize yield (4 t ha−1) was similar among the three methods. Agronomic use efficiencies of P and K (300 and 250 kg kg−1, respectively) were higher with NE than with the blanket recommendation (150 and 70 kg kg−1). In Ethiopia, NE and soil-test based respectively recommended lower amounts of P by 8 and 19 kg ha−1 than the blanket recommendations, but maize yield (6 t ha−1) was similar among the three methods. Overall, fertilizer recommendations generated with NE maintained high maize yield, but at a lower fertilizer input cost than conventional methods. NE was effective as a simple and cost-effective decision support tool for fine-tuning fertilizer recommendations to farm-specific conditions and offers an alternative to soil testing, which is hardly available to most smallholder farmers.

Combinations of a biofertilizer with micro-dosed chemical fertilizers increased yield of maize in a high acid saturated soil

Maize yields are usually lower for small-scale farmers relative to commercial farmers due to uncontrolled root diseases, acidic and nutrient deficient soils. Fertilizer micro-dosing is a promising strategy that has been earmarked to complement traditional fertilizer management strategies. However, this strategy is rarely known regarding its performance in maize systems in Southern Africa. The study was conducted over two seasons aiming at developing cost effective strategies on liming and fertilization to increase maize yields for farmers with low affordability and high acid saturated soils. Soil type used in this study had an acid saturation of 54% requiring 4.5 tons ha−1 dolomitic lime to obtain 4 tons ha−1 maize grain yields. Micro-dosing of NPK 2:3:2(34) fertilizer; superphosphate fertilizer and dolomitic lime were exploited to increase maize grain yields in a high acid saturated soil over time to cater for the farmer's affordability. A formulation of Bacillus megaterium was used as a biofertilizer. Micro-dosing of NPK 2:3:2(34) fertilizer increased maize yields by 64.6% (Season 1) and 13.6% (Season 2) when compared to the control treatment (unfertilized control) over the two seasons. Micro-dosing with superphosphate fertilizer alone significantly (P = 0.001) increased maize yield in Season 1 by 50.5% and Season 2 by 37.4% relative to the control. The combination of B. megaterium and micro-dosed NPK 2:3:2(34) fertilizer significantly (P = 0.001) increased maize yield in both seasons by 54.7% and 48.1%, respectively in comparison to the control. Whenever B. megaterium was included in the treatment combinations, there was a further increase in maize grain yield in both seasons. In all micro-dosing combinations where NPK 2:3:2(34) fertilizer and superphosphate were present, fertilizer use efficiency (FUE) were lower than micro-dosing of either NPK 2:3:2(34) fertilizer or superphosphate alone. The combination of precision placement of micro-dosed fertilizers and lime with B. megaterium may be a solution for small-scale farmers who have soils with high acid saturation.

Greater maize yield improvements in low/unstable yield zones through recommended nutrient and water inputs in the main cropping regions, China

Maize (Zea mays L.) is an important cereal crop grown worldwide. With the increase in human food demand but limited land and water resources, precise spatially explicit knowledge about the maize production capacity through agricultural management practices (e.g., using recommended nutrient and water inputs, RNWI, by local agronomists) is essential to guide the future policy, research, development, and investment. Here, we used a well-validated crop model (APSIM-Maize) for 1981–2010 combined with actual climatic and soil data to estimate maize yield improvements under RNWI in three main cropping regions in China (the North China Spring Maize Region, NCS; the Huanghuaihai Summer Maize region, HS; and the Southwest China Mountain Maize Region, SCM). Compared with the county-level maize actual yield in the three main cropping regions, the average maize yield could be increased by 33 % (4 Mg ha−1) through RNWI, while the improvements in the coefficients of variation (CVs) of grain yield and reliable grain production (RGP) were 0.11 and 32 % (69 million Mg), respectively. Except for RNWI, the average yield, CVs of yield, and RGP could still be increased by 28 % (3 Mg ha−1), 0.10, and 36 % (80 million Mg) through other management and technologies (OMT). Further analysis in four types of yield level-stability zones (high-stable, low-stable, high-unstable, and low-unstable zones) showed that greater contributions of using RNWI and OMT to improve maize grain yield, yield stability, and RGP were found in zones with low/unstable yield across the three regions. The findings highlighted the focus on increasing maize yield in low/unstable-yield zones could provide a greater return.

Comparative Performance of Organic Fertilizers in Maize (Zea mays L.) Growth, Yield, and Economic Results

Maize is a major crop grown and consumed in Uganda and it requires a high fertilizer input. However, the existing inorganic fertilizers in the market are often not affordable especially to small scale farmers, which results in decreased maize yields in the country. On the other hand, there is an abundance of unutilized animal manure, which, when treated, can be used to increase maize yields. This study evaluated the response of maize to products of different cattle manure treatment methods as well as inorganic fertilizer. The treatments such as cattle manure stored under shade (T), cattle manure stored in the open (M), cattle manure slurry digestate (S), vermicompost (V), and an inorganic fertilizer, DAP (D) were all applied in completely randomized block plots at an equal application rate of 50 kg N ha−1 with four replications per treatment. Control plots (C) where no fertilizer was applied were also considered. The experiment was done for two planting seasons in 2018. Number of leaves, plant height, cob, and grain yields were used to evaluate the performance of different fertilizer treatments. Economic assessment of all the six treatments was also carried out to determine the economic viability of applying these fertilizers on maize. Maize growth parameters and yields were all significantly increased (p &lt; 0.05) with an application of both organic and inorganic fertilizers when compared with the control. However, there was no significant difference (p &gt; 0.05) in the maize yields under the different fertilizer treatments. Vermicomposting was the most economically viable manure treatment method due to low operating costs and higher returns on investment that are supplemented with the production of chicken fodder (earthworm biomass) and, thus, can be recommended to farmers for production of a fertilizer that increases maize yields with assurance of economic returns.

Effectiveness of Inorganic Fertilizer and Biofertilizer Application on Maize Yield and Fertilizer Use Efficiency on Inceptisol from West Java

The study about the effectiveness of inorganic fertilizer and bio-fertilizer application on maize yield and fertilizer use efficiency has been carried out in the greenhouse using Inceptisol from Dukuh Village, Cibungbulang District, Bogor Regency. Inorganic fertilizers used were Urea, SP36 and KCl, the biofertilizer used consisted of Azospirillum sp., Azotobacter sp., Bacillus sp., and Lactobacillus sp.. The study was arranged in a Randomized Block Design consisting of seven treatments and six replications. The treatments consisted of various dosages of inorganic fertilizers combined with bio-fertilizer, namely 1) Control (without fertilizer), 2) 100% recommended NPK level, 3) Biofertilizer, 4) 25% recommended NPK level+Biofertilizer, 5) 50% recommended NPK level+Biofertilizer, 6) 75% recommended NPK level + Biofertilizer, 7) 100% recommended NPK level + Biofertilizer. The results showed that the application of inorganic NPK ferttilizers and biofertilizer on maize cultivation on Inceptisol from Dukuh Village, Cibungbulang District, Bogor Regency resulted in an increase of maize yield compared to the recommended level of inorganic fertilizers (100% NPK). The treatment of NPK (50% recommended level)+Biofertilizer resulted in the highest biomass dry weight, yield of corn and value of RAE (Relative Agronomic Effectiveness). The shoot dry weight was 138.09 g pot-1, corn yield was 190.87 g pot-1, and RAE value was 113.44%. The optimum doses of NPK fertilizers were 200 kg Urea ha-1, 60 kg SP-36 ha-1 and 45 kg KCl ha-1 combined with 4 L ha-1 biofertilizer.

Bioeconomic evaluation of allelopathic crop leachates integrated with reduced doses of herbicide for horse purslane management in maize under field conditions

Background: Continuous use of commercial herbicides is posing a severe threat to environment and creating herbicide resistant weeds. Allelopathy offers a promising alternative to commercial herbicides for sustainable weed management. The farmers are highly concerned with maximum yield as well as cost of the weed control techniques. Objective: To investigate economic and weed control efficiency of allelopathic crop water leachates mixed with lower rates of herbicide. Methods: Rapeseed (Brassica napus L.), sunflower (Helianthus annuus L.) and sorghum (Sorghum bicolor L.) crop leachates (18 L ha-1 each) tank mixed with lower doses (25, 33 and 50% of recommended dose) of S-metolachlor+atrazine were sprayed as pre-emergence for horse purslane (Trianthema portulacastrum L.) management in maize (Zea mays L.). Label dose (1,080 g a.i. ha-1) of herbicide (S-metolachlor+atrazine) and a weedy check treatment were also maintained. Results: The results showed that rapeseed+sunflower+sorghum allelopathic leachates mixed with half dose (540 g a.i. ha-1) of S-metolachlor+atrazine was effective against horse purslane and increased maize yield (grain) by 45% and 5% as compared with control and label dose of herbicide, respectively. Likewise, economic analysis showed that the same treatment was most economical with 40% and 9% higher net benefits than control and label dose of herbicide, respectively and 2407% marginal rate of return. It also gave an additional benefit of US$ 24.07 for investment of every US$1. Conclusions: By using this technique, herbicides use can be minimized by 50% for sustainable weed management without compromising maize yield and net benefits.

Effects of fertilizer management strategies on maize yield and nitrogen use efficiencies under different densities

AbstractRational plant density and fertilizer management are important practices to improve maize (Zea mays L.) yield and nutrient use efficiency. Previous research indicated that plant density and fertilization had positive interaction on maize yield and N utilization. The research studied on the interactive effects of slow‐released fertilizer (added amino acid polymer biological preparation) and density on maize yield and nitrogen use efficiencies (NUEs). A 2‐yr field experiment with varieties Suyu29 (SY29) or Suyu30 (SY30) was conducted using a split‐split plot design. Three densities (6.0, 7.5, and 9.0 × 104 plants per ha) and three fertilization modes (0F‐no fertilizer, SF‐one‐time application of slow‐released fertilizer, and CF‐twice application of conventional fertilizer) were assigned. Results indicated that grain yields and NUEs of SF under 7.5 × 104 plants per ha were the highest both in SY29 and SY30. Compared with CF under 7.5 × 104 plants per ha, SF could improve pre‐ and post‐silking N uptake and promote N translocation from stalk and leaf into grain, which increased its contribution efficiency to grain N content and obtained higher NUE. The average N partial productivity, N agronomic efficiency, N recovery efficiency, and N absorption efficiency of SF were 5.3, 9.9, 20.1, and 11.4% higher than CF under 7.5 plants × 104 plants per ha. Increasing plant density, the grain yield, total N accumulation, and NUEs initially increased and then decreased both in SF and CF. These results suggest that one‐time application of SF combined with appropriate density could increase maize yield and NUE under our experiment condition.