Fertilizer Requirements Of Crops Research Articles

Simulation analysis of the fertilizer ejecting device of corn fertilizer applicator based on EDEM

In order to improve the fertilization efficiency of corn fertilizer applicator in the Huang-Huai-Hai area, according to the requirements of the wide-row crop fertilizer requirements, a centralized type fertilizer ejecting device was designed. Straight outer groove-wheel was regarded as research objects in this paper. The simulation model of fertilizer ejecting device was established and the simulation analysis of fertilizer ejecting was carried out by using the discrete element simulation software (EDEM). In the simulation environment, the requirement of fertilizer ejecting amount was 300kg·hm-2, the forward speed of fertilizer ejecting device was set to 5.4km·h-1, and the working height of fertilizer axis was 250mm. The effect of different working lengths of fertilizer ejecting wheels on the fertilizer performance was analyzed. The simulation results showed that when the working length of fertilizer ejecting wheel was 28mm, the uniformity variation coefficient of fertilizer ejecting was 14.62%, and the accuracy rate of fertilizer ejecting was 95.95%, which indicated that performance of fertilizer ejecting was better. This research results can provide references for the subsequent development of corn fertilizer applicator.

Effects of nitrogen rate and harvest time on biomass yield and nutrient cycling of switchgrass and soil nitrogen balance in a semiarid sandy wasteland

Increasing demand for renewable energy has stimulated energy crop cultivation on marginal lands with low production potential. This study investigates potential biomass yield of switchgrass (Panicum virgatum L., cv. Blackwell), plant nutrient (nitrogen, N; phosphorus, P; potassium, K) concentration and uptake, N-use efficiency (NUE) and apparent soil N balance in a semiarid rainfed sandy wasteland of Inner Mongolia, China. The aim of this study was to optimize N fertilizer rate and harvest time to produce quality biomass sustainably with minimal soil nutrient removal through harvested crop biomass. Five N rates (0, 60, 120, 180, 240 kg N ha−1) and two harvest times (late summer and early fall) in one-cut system were evaluated in 2015 and 2016. Nitrogen application of 60 kg N ha‒1 significantly increased aboveground plant (AGP) biomass yield by 14.3% vs. control only during early fall harvest in 2016, with no yield response at rates >60 kg N ha−1. AGP nutrient concentration and nutrient uptake increased by increasing N rate, except for P concentration, which decreased. Partial factor productivity (PFP) and agronomic NUE (ANUE) of applied N fertilizer decreased quadratically with N rates >60 kg N ha−1. Apparent soil N budget study revealed an N deficit (0–20 cm depth) in control while N surplus increased as N rate increased which likely boosted NO3- leaching. An early fall harvest exhibited 12.5% higher biomass yield and substantially reduced biomass N and K concentration and uptake relative to late summer harvest. These findings demonstrate that an N input not exceeding 60 kg N ha−1 would be sufficient to optimize biomass yields of Blackwell switchgrass and maintain the soil N balance on a semiarid rainfed sandy wasteland of Inner Mongolia when harvested in early fall. Therefore, N fertilization and harvest time practices should be considered simultaneously in switchgrass production systems for the continuous and sustainable biomass supply with increased feedstock quality and reduced crop fertilizer requirements.

Learning from the soil’s memory: Tailoring of fertilizer application based on past manure applications increases fertilizer use efficiency and crop productivity on Kenyan smallholder farms

Abstract The large uncertainty in yield response to fertilizer application within smallholder cropping systems in sub-Saharan Africa (SSA) limits efforts aimed at intensifying crop production based on increased fertilizer application. We assessed the key field-scale cause of variability in maize (Zea mays) grain yield response to fertilizer nitrogen (N), phosphorus (P) and potassium (K) in the Sidindi area of Western Kenya based on past manure application, distance from the homestead, and clay and silt contents. We used data from nutrient omission trials conducted on 23 farms over seven consecutive cropping seasons covering the period 2013–2016, without changing treatments or plot location. Treatments included a control and PK, NK, NP and NPK. Accounting for past manure application increased the explained variability in maize yield, and yield response to N, P, and K application. Mean treatment maize grain yield in the control, PK, NK, NP and NPK treatments were 1.0, 2.2, 1.5, 2.9 and 4.5 t ha−1 at 88% dry matter respectively in fields without past manure application, and 2.4, 2.7, 4.4, 4.9 and 5.4 t ha-1 in fields which had received animal manure in at least two out of three seasons prior to the start of the trials. Mean maize yield response to N, P and K application was 2.3, 3.0 and 1.6 t ha−1 respectively in fields without past manure application, and 2.8, 1.1 and 0.6 t ha−1 in fields with past manure application. In the seventh cropping season, past animal manure application contributed a fertilizer equivalent of 28.3, 29.8 and 31.5 kg ha−1 of N, P and K, respectively. At both the onset and at the start of the last season, fields with past animal manure application had on average higher contents of SOC, available P and exchangeable K, yet differences were not always significant within treatments. Accounting for past animal manure application reduces crop fertilizer requirements for P and K as well as decreasing uncertainty in yield response to fertilizer. We conclude that the strong influence of past animal manure application on yield response to fertilizer application merits the inclusion of past manure application as a co-variate in analysis of yield response data from smallholder cropping systems of SSA.

Phosphorus Adsorption Isotherm: A Key Aspect for Effective Use and Environmentally Friendly Management of Phosphorus Fertilizers in Calcareous Soils

ABSTRACTCrop response to the phosphorus (P) application is often erratic in most soil types in the world. In Algeria, there is no information on the P behavior in calcareous soils. The purposes of this work were to investigate the degree of P fixing capacity and to predict P fertilizer requirements of crops according to calcareous levels in the soil. Soil samples (at 0–30 cm depth) were collected and spiked with 0, 25 and 50% of lime (CaCO3). Phosphate sorption curves were well fitted to the Freundlich equation. Results indicated that the calcareous level was predominantly controlled the P sorption indices [sorption capacity (a), and P sorption energy (n)] to affect the estimation of external d P requirement (EPR0.2) and P fertilizer rates. The understanding of P sorption and desorption by soils and extrapolating the developed relationship between soil calcareous contents and P fertilizer rates would be quite promising and accurate approach for the economic and effective use of P fertilizers in calcareous soils of Algeria.

Improving phosphorus efficiency in cereal crops: Is breeding for reduced grain phosphorus concentration part of the solution?

Given the non-renewable nature of global phosphate reserves, there is a push to increase the phosphorus (P) efficiency of agricultural crops. Research has typically focussed on investigating P acquisition efficiency or internal P utilization efficiency to reduce crop fertilizer requirements. A novel option that would reduce the amount of P exported from fields at harvest, and may ultimately reduce P fertilizer requirements, would be to reduce the amount of P translocated to grains to minimize grain P concentrations. While such a trait has been mentioned in a number of studies over the years, there has not been a concerted effort to target this trait in breeding programs. In this perspective piece we explore the reasons why a low grain P trait has not been pursued, and discuss the potential benefits and drawbacks of such a trait in the context of breeding to improve the P efficiency of cropping systems.

English

In most developing countries including Nigeria, fertilizers are applied to the soil by uneducated farmers without particularly making reference to the specific need of the plant or soil. Therefore, intended efficiency/replenishment is not maximized and fertilizer use is not rationalized. This paper critically reviews the three basic approaches to soil fertility evaluation: Visual symptoms of nutrient deficiency, Plant tissue analysis and soil testing. The implications of these methods are examined in terms of predicting fertilizer requirements for crops in Nigeria. Furthermore, the paper discusses the methods of Soil fertility evaluation available. Focus is then shifted primarily to the soil testing method, describing in detail the main objectives behind carrying out soil testing, including the proper soil sampling tools, sound sampling techniques and handling of the samples. Key words: Soil fertility evaluation, fertilizer, soil sampling, Nigeria.

Legumes for mitigation of climate change and the provision of feedstock for biofuels and biorefineries. A review

Legumes for mitigation of climate change and the provision of feedstock for biofuels and biorefineries. A review

Calibration of Soil Test for Mineral Nitrogen in Poland

The mineral nitrogen (Nmin) method is generally accepted as the universal soil test for determining crop fertilizer requirements and predicting the possibility of groundwater contamination by excess nitrates (NO3). However, it must be properly calibrated both for agronomic and environmental purposes. Since 1997, the program of soil monitoring for the content of Nmin has been running in Poland. In 5,000 randomly selected sites on arable land, soil samples are collected twice a year (in early spring and autumn) from soil layers 0–30, 30–60, and 60–90 cm deep. The frozen samples are sent to the one of 17 regional agrochemical laboratories and analyzed for the content of nitrogen (N)–NO3 and N‐ammonium (NH4). The results, expressed in kg of Nmin in the given soil layer and/or in the soil profile at 0–90 cm, are collected in the data bank at the Institute of Soil Science and Plant Cultivation, State Research Institute, Puławy. These data are made available for farmers and environment protection services. On the basis of about 75,000 data already collected, the calibration of Nmin method was accomplished, and the results presented as the normatives of Nmin content in spring and autumn. The distribution of data was far from normality, and therefore the median value was used as a characteristic of central point and percentile as a measure of distribution. Similar to the five classes of soil reaction and Phosphorus (P), potassium (K), and magnesium (Mg) contents officially used in Poland, five intervals of Nmin content were proposed. Each interval contains 20% of ordered observations, and thus five classes of Nmin were distinguished: very low, low, medium, high, and very high. Because of the significant Nmin dependency on soil texture (very light, light, medium, heavy), altogether 20 normatives of Nmin are included in the calibration table. In the article, the method of simulation of nitrate concentration in soil solution in the soil layer at 60–90 cm, assuming soil saturation to full water capacity, is presented as well.

Integrating Hoop House Construction and Operation into an Undergraduate General Education Horticulture Class

We integrated the construction and operation of hoop houses into a general education course to provide students with basic agriculture skills such as basic agricultural construction, greenhouse crop production, and greenhouse environmental data collection, while immersing them in an experiential learning environment. Students in the class constructed three 12 × 15-ft hoop houses, installed an irrigation system and climate data acquisition system, and grew radish (Raphanus sativus ‘Cherry Belle’) and lettuce (Lactuca sativa ‘Black-Seeded Simpson’) within each hoop house. At the end of the exercise, 86% of students agreed that they knew the basic techniques of hoop house construction, and 89% agreed that they understood the practical application of building a hoop house. More instruction on calculating crop fertilizer requirements would benefit students because only 43% of students agreed or strongly agreed that they understood how to compute crop fertilizer requirements. Climate data demonstrated that air temperature within the unvented hoop houses exceeded the optimal growing temperature for lettuce and radish. We conclude that construction and operation of hoop houses provided practical agricultural skills in an experiential learning environment while revealing subject areas that warrant further instruction.

Integrating Hoop House Construction and Operation into an Undergraduate General Education Horticulture Class

We integrated the construction and operation of hoop houses into a general education course to provide students with basic agriculture skills such as basic agricultural construction, greenhouse crop production, and greenhouse environmental data collection, while immersing them in an experiential learning environment. Students in the class constructed three 12 × 15-ft hoop houses, installed an irrigation system and climate data acquisition system, and grew radish (Raphanus sativus ‘Cherry Belle’) and lettuce (Lactuca sativa ‘Black-Seeded Simpson’) within each hoop house. At the end of the exercise, 86% of students agreed that they knew the basic techniques of hoop house construction, and 89% agreed that they understood the practical application of building a hoop house. More instruction on calculating crop fertilizer requirements would benefit students because only 43% of students agreed or strongly agreed that they understood how to compute crop fertilizer requirements. Climate data demonstrated that air temperature within the unvented hoop houses exceeded the optimal growing temperature for lettuce and radish. We conclude that construction and operation of hoop houses provided practical agricultural skills in an experiential learning environment while revealing subject areas that warrant further instruction.

Microbial activity and soil C sequestration for reduced and conventional tillage cotton

Crop management practices, such as tillage and diversified crop rotations, impact microbial activity, organic matter turnover, and ultimately soil C and N sequestration. The objectives of this study were to determine the impacts of tillage on soil microbial biomass, mineralized C and N, and soil organic C (SOC) and N (SON) contents for different cotton ( Gossypium hirsutum L.) cropping systems in a south-central Texas silt loam soil. Tillage influenced SOC and SON, but most effects were observed at 0–5 cm rather than 5–15 cm. Reduced tillage (RT) in a continuous cotton monoculture increased SOC by 24% and SON by 27% compared to conventional tillage (CT) at 0–5 cm, but tillage had no effect at 5–15 cm. Crop rotation increased soil C and N contents compared to continuous cotton, as a cotton-corn ( Zea mays L.) rotation under CT increased SOC by 28% and SON by 26% at 0–5 cm compared to CT continuous cotton. Soil organic C and SON were both 18% greater for cotton-corn than continuous cotton at 5–15 cm. For the 0–15 cm depth interval, the CT cotton-corn rotation increased SOC by an average of 518 kg C ha −1 year −1 and SON by 57 kg N ha −1 year −1 compared to CT continuous cotton. Cotton under RT sequestered 254 kg C ha −1 year −1 and 33 kg N ha −1 year −1 more than cotton under CT. Reduced tillage increased soil microbial biomass C (MBC) by an average of 11 and 18% compared to CT continuous cotton and the cotton-corn rotation, respectively, while microbial biomass N (MBN) for RT was 62% greater than for CT. Tillage decreased mineralized C and N at both depth intervals, while cotton-corn showed higher mineralized C than continuous cotton. Soils for cropping systems that sequestered the most C and N also had the highest microbial biomass and mineralized C and N, indicating close relationships between microbial activity and soil C and N sequestration. Beneficial effects of RT and intensive cropping were enhanced soil C and N sequestration rates and potentially lower N fertilizer requirements for crops.

Quantity and Quality of Runoff from a Beef Cattle Feedlot in Southern Alberta

Southern Alberta, which has a cold climate dominated by strong chinook winds, has the highest density of feedlot cattle in Canada. However, the quantity and quality of runoff from beef cattle (Bos taurus) feedlots in this unique region has not been investigated. Our objectives were to compare runoff quantity (1998-2002) with catch-basin design criteria; determine concentrations of selected inorganic chemical parameters (1998-2000) in runoff in relation to water quality guidelines and the potential implications of irrigating adjacent crop-land; and determine if total heterotrophs, total coliforms, and Escherichia coli (1998-2000) persisted in the catch-basin water and soil. Runoff (< 0.1 to 42.5 mm) for a 24-h duration that included maximum peak discharge was less than the recommended design criteria of 90 mm based on runoff from 24 h of rainfall with a 30-yr return period. We found that curve numbers between 52 and 96 (mode of 90) were required to match the USDA Natural Resources Conservation Service predicted runoff and actual runoff volumes. Total P posed the greatest threat to water quality guidelines, and K posed the greatest threat for exceeding crop fertilizer requirements if catch-basin effluent was used as irrigation water. Water in the catch basin had continually high populations of E. coli throughout the study, with values ranging between log10 2 and log10 8 100 mL(-1). In contrast, soil in the catch basin generally had low populations of E. coli that were < log10 2 g(-1) wet wt., but at times higher populations between log10 2 and log10 6 g(-1) wet wt. were also found.

Effect of cropping systems on nitrogen mineralization in soils

Understanding the effect of cropping systems on N mineralization in soils is crucial for a better assessment of N fertilizer requirements of crops in order to minimize nitrate contamination of surface and groundwater resources. The effects of crop rotations and N fertilization on N mineralization were studied in soils from two long-term field experiments at the Northeast Research Center and the Clarion-Webster Research Center in Iowa that were initiated in 1979 and 1954, respectively. Surface soil samples were taken in 1996 from plots of corn (Zea mays L.), soybean (Glycine max (L.) Merr.), oats (Avena sativa L.), or meadow (alfalfa) (Medicago sativa L.) that had received 0 or 180 kg N ha–1 before corn and an annual application of 20 kg P and 56 kg K ha–1. N mineralization was studied in leaching columns under aerobic conditions at 30 °C for 24 weeks. The results showed that N mineralization was affected by cover crop at the time of sampling. Continuous soybean decreased, whereas inclusion of meadow increased, the amount of cumulative N mineralized. The mineralizable N pool (N o) varied considerably among the soil samples studied, ranging from 137 mg N kg–1 soil under continuous soybean to >500 mg N kg–1 soil under meadow-based rotations, sampled in meadow. The results suggest that the N o and/or organic N in soils under meadow-based cropping systems contained a higher proportion of active N fractions.

Assessing the fertilizer phosphorus requirement of grain sorghum

Assessing the fertilizer phosphorus (P) requirements (FPR) of crops is an important component of research for efficient and rational use of fertilizers. Soil and plant tests are employed to determine the FPR. Two methods were evaluated for determining the FPR of sorghum grown on a Vertisol under rainfed conditions. The first method was based on P on applied P uptake, and grain yield relationships for grain sorghum. In this method, P uptake at a given yield was determined from the relationship between total P uptake and grain yield. The amount of fertilizer P applied for the given P uptake and grain yield was then, determined from the relationship between P applied and P uptake. In the second method, FPR was determined using the equation: FPR=(Up‐U0)/PRF, where Up is P uptake at a given yield, U0 is P uptake from unfertilized soil, and PRF is the recovery of applied P. The parameters, U0, Up, and PRF were determined in a field experiment with sorghum grown on a Vertisol under rainfed conditions. There was a good agreement between the observed value of FPR and predicted values determined by the two methods. These results suggest that the simple models based on P uptake can be utilized for determining the fertilizer requirements of crops.

The interpretation of Olsen extractable P values in relation to recommendations for the fertilizer requirements of crops

A greenhouse experiment, with Okra (Abelmoschus esculentus L.) as the test crop, was conducted on twenty-one soils ranging in Olsen's extractable phosphorus from 1.8 to 15.5µg Pg−1 soil. The experiment was conducted at Punjab Agricultural University, Ludhiana, India. The soils were nonsaline with pH ranging from 7.7 to 8.6. A critical level of 2.55µg Pg−1 soil was predicted by Cate and Nelson's (1971) statistical procedure. Because of a wide range in relative yields, this value did not accurately predict response to applied P. An approach to compute minimum response to applied fertilizer, which is likely to be obtained at a particular Olsen P level, has been presented. It involves calculation of lower 60 percent confidence limits for relative yield and fitting loge-linear regression to the transformed data. The regression was tested on a published data set and was found to hold well.

Leaf analysis as a guide to sulfur fertilization of legumes

Abstract Tissue analysis is a diagnostic tool which can be used in identifying S deficiencies and predicting S fertilizer requirements of crops. A water extraction procedure for removal and measurement of inorganic sulfate in plant leaves was developed and assessed as a measure of S availability in four legume crops. Relationships between sulfate concentration and yield were determined for alfalfa (Medicago sativa L.), chickpea (Cicer arietinum L.), faba bean (Vicia faba) and lentil (Lens culinaris) grown on two Saskatchewan soils, with five rates of S fertilizer supply, in a growth.chamber experiment The sulfate concentration in the leaf tissue was measured at the time of seventh leaf and early flowering stages to estimate the current S status of the plants. The results showed significant relationships between the water extractable sulfate in the leaf and the supply of available S in the soils. The water extraction procedure is recommended for routine analyses because of its simplicity and sensitivity.

A fertigation system for experimental purposes

The widely accepted application of the fertilizers via the irrigation stream (fertigation) has necessitated the development of suitable techniques to help research in estimating the fertilizer requirements of crops. This paper describes a simple, inexpensive, and precise system tested for three years in field experiments, in which various levels of a fertilizer could be supplied simultaneously. The same system could also be used when irrigating simultaneously various crops with different fertilizer requirements from a single concentrated fertilizer solution, using only one fertigator.

Estimation of potentially mineralizable soil nitrogen from chemical and taxonomic criteria

Abstract Estimates of mineralization of soil organic N are often needed to predict N fertilizer requirements of crops. G. Stanford and his collaborators developed laboratory techniques to estimate potentially mineralizable N (NO) in soils and a rate constant for mineralization (k). Their techniques have been used to estimate N mineralization in the field. This study reports the use of stepwise multiple regression techniques to estimate N from soil pH, organic carbon concentration, total N concentration, and soil taxonomy. The regression equation for No accounted for 83% of the variation of No for 90 samples from 67 soils representing eight soil orders. The regression equation for k accounted for 40% of the variation in the rate constant k for 61 samples from 43 soils. These results should aid in the estimation of N mineralization in cases where laboratory measurements of N and k are not available.

Some problems in the estimation of simultaneous fertilizer requirements of crops from response surfaces

The estimation of the optimal fertilizer requirements of a crop from the data of fertilizer experiments depends on the response exhibiting the form of the law of diminishing returns with respect to all fertilizers. Deviations from the diminishing form are frequently encountered, particularly with experiments involving several fertilizers, because of experimental errors, extrapolation errors, and inappropriate choices of fertilizer treatment levels. Since the time required to repeat inadequate experiments is usually considerable the experimenter has to make the best use of admittedly inadequate data to obtain interim estimates of fertilizer requirements. A procedure is described for obtaining estimates of fertilizer requirements with such data despite the deviations from the expected diminishing response form. The procedure is based on the use of a polynomial model to represent the multidimensional response surface. Interaction terms which would normally be expected to make only small and negligible contributions to the model, are eliminated to avoid the influence of non-significant responses to particular fertilizers on the calculation of other fertilizer requirements. Where a fertilizer has given a significant but non-diminishing response, approximate estimates of the requirements of that fertilizer are substituted to allow approximately for interaction effects in the estimation of the remaining fertilizer requirements. The problems and the application of the procedure is illustrated with data from three fertilizer experiments involving nitrogen, phosphorus, potassium, and sulphur fertilizers.

Plant Analysis and Fertilizer Requirements

A QUICK and reliable method of determining the fertilizer requirements of crops and of discovering what nutrient deficiency is responsible for the unsatisfactory growth of some particular crop would be of immense value in advisory work. The problem can be approached from several different points of view, such as soil analysis, field trials, pot cultures, leaf injection, plant analysis and the use of visual symptoms. The relative advantages and disadvantages of these various methods of diagnosing fertilizer requirements are briefly but clearly summarized in the paper under notice*, and an extensive list of references facilitates fuller study of the individual methods.