Starter Fertilizer Application Research Articles

The role of zinc fertilization and its interaction with nitrogen and phosphorus starter fertilization on early maize development and grain yield

The early planting of maize in temperate growing areas leads to yield and quality benefits, although a low soil temperature can affect the early nutrient uptake and delay plant development. Not only can the nitrogen (N) and phosphorus (P) uptake be limited, but that of zinc (Zn) can also be affected. Moreover, the application of N and P at early growth stages can result in an enhancement of maize growth. Two field experiment were carried out in North Italy during the 2012–14 period to: i) evaluate the most effective Zn application strategy by comparing seed, soil and foliar applications with an untreated control; ii) investigate the role of a Zn seed treatment on the early development and yield of maize grown in three different types of soils. The effect of Zn application was compared, in both experiments, to starter NP fertilization in bands at planting, according to a full factorial design. Zn fertilization significantly enhanced the early vigor and yield of the maize, although the effects were less pronounced than those of the NP fertilizer. Among the Zn fertilization strategies, maize growth was quicker for the seed and soil applications than for the foliar application or the untreated control. The former application significantly increased the plant height at stem elongation (+32%), shortened the planting-flowering period by 1 day, and increased the grain yield by 4%. Overall, the application of NP starter fertilizer shortened the planting-flowering period by 4.5 days and increased the yield by 10%, compared to the unfertilized control. In the second experiment, higher plant vigor indices were detected in all the soils for the NP starter fertilization (+22–27%) and for the Zn seed treatment (+3–9%) than in the controls. The NP starter fertilization reduced the grain moisture at harvest by 2.3% and increased grain yield by 14%, while the Zn treatment significantly increased the kernel weight but did not affect the grain yield or the moisture content. The interaction between the NP fertilization and the Zn treatment was never significant. Thus, the positive effect of Zn on the early vigor was an additional benefit to that produced by the starter NP fertilization. The study demonstrated that a Zn application at planting, with both a seed dressing and a soil treatment, significantly enhanced the early growth of different maize hybrids, in different growing seasons and soils, although the use of a NP starter fertilization led to more consistent agronomic benefits. Furthermore, the combination of NP and Zn starter fertilization resulted in a further advantage for all the considered production situations.

Response to side-banded phosphorus and zinc fertilizer for corn grown after canola or soybean in southern Manitoba

A 2-year crop rotation study in southern Manitoba assessed the effects of starter fertilizer on grain corn ( Zea mays L.) production when corn followed canola ( Brassica napus L.) versus soybean ( Glycine max L. Merr.). Treatments included a control (no starter) and two rates of phosphorus (P) (30 and 60 kg P2O5 ha−1) as monoammonium phosphate (MAP, 11–52–0) or MicroEssentials® SZ (MESZn, 12–40–0–10–1) side-banded at planting. The preceding crop did not have any influence on mycorrhizal colonization of corn roots at the V4 corn growth stage. However, side-banded fertilizer increased early-season biomass by as much as 111% compared to the unfertilized control, averaged across all site-years, with the largest increases occurring where corn followed canola. P concentration and uptake in early-season biomass increased as the P rate increased. Zinc (Zn) concentrations in early-season biomass were the greatest for the unfertilized control and MESZn treatments, while Zn uptake was significantly greater with the application of starter fertilizer compared to the unfertilized control. Starter P advanced silking date by 2–7 days relative to the unfertilized control. At maturity, starter P reduced grain moisture by 21–27 g kg−1 in corn only after canola. The high rate of MAP increased grain yield by an average of 770 kg ha−1 compared to the unfertilized control, regardless of the preceding crop. The negative influence of the preceding canola crop on early-season growth and mid-season development of corn can be managed with starter fertilization to provide adequate P and Zn to the corn crop and maintain successful production in Manitoba.

Effect of foliar mineral fertilizer and plant growth regulator application on seed yield and yield components of soybean (Glycine max) cultivars

Soybean is known for its high protein content, which is the reason why it is widely used as one of the main food sources for humans and animals. In order to increase soybean yield, farmers tend to use foliar mineral fertilizer and plant growth regulator to this crop. Furthermore, a starter fertilizer application into the soil without foliar application may cause low yield contents of soybean. The aim of this investigation was to estimate the effects of different foliar mineral fertilizers (MF) and plant growth regulator (RGR) application on quantitative traits (plant height (PH), lower pods attachment height (LPH), number of seed pods per plant (NSPP), number of seeds per plant (NSP), weight of seeds per plant (WSP) and 1000-seed weight (TSW) and soybean grain yield (SGY)) in three soybean cultivars (Lastochka, Akku and Galina) in Shymkent of the Turkestan region, Kazakhstan. Four treatments of fertilization were tested: control (starter fertilizer, Р60К45), Р60К45 + Mo+B, Р60К45 + Epin and Р60К45 +Vuksal. Mo+ B, Epin and Vuksal were foliar applied one-two times at growth stage. The field experiments were carried out in South-Western Research Institute of Animal Husbandry and Plant Growing, during the years 2019, 2020 and 2021. In both research years, Akku had higher values for all investigated traits than Lastochka and Galina. Results showed that foliar MF and PGR application significantly increased the values for PH, LPH, NSPP, NSP, WSP, TSW and SGY. Vuksal is more effective than Epin and Mo,B in soybean cultivars because Vuksal is a liquid fertilizer that contains has higher concentration of macronutrients (16%N, 16%P2O5, 12%K2O+me, w/v). Generally, cultivar Akku and treatment starter fertilizer (Р60К45) + Vuksal (2,5 L/ha) may be recommended in soybean production in localities with similar agro-ecological conditions.

Nitrate losses in subsurface drainage and nitrous oxide emissions from a winter camelina relay cropping system reveal challenges to sustainable intensification

Sustainable intensification strategies seek to increase production while decreasing the environmental footprint of agricultural systems. In the Upper Mississippi River Basin, relay cropping of a winter oilseed crop between corn and soybean has gained interest for its potential to increase total yields and revenue while providing the environmental benefits of winter cover. In a six-year field study in central Iowa, a basic corn-soybean rotation was compared with a corn-winter camelina-soybean relay cropping system for crop yields, nitrate losses in drainage, and nitrous oxide (N2O) emissions from soil. Despite filling a niche as an overwintering crop with the potential to assimilate soil nitrogen, nitrate loads in drainage were not reduced in the camelina relay cropping system. Over the course of the study, management changes to support the camelina crop tripled cumulative N2O emissions during the camelina-soybean phase, from 3.57 kg N2O-N ha-1 in the basic corn-soybean rotation to 12.2 kg N2O-N ha-1 in the camelina relay system. Most of the increased emissions in the camelina system were associated with peak emissions events following tillage and starter fertilizer application in the fall and during the spring thaw, which may point to risks of exacerbating greenhouse gas emissions during fall management of a relay crop. Corn and soybean yields were decreased in the relay cropping system by 9.8 % and 23.3 %, respectively, as a result of management changes to the system and interspecific competition. However, combined grain dry weight of soybean and the camelina oilseed crop were similar to the soybean yield in the basic corn-soybean rotation. These findings highlight the need for careful evaluation and optimization of sustainable intensification systems to ensure environmental and production goals are met.

The synergistic effect of nitrogen and phosphorus starter fertilization sub-surface banded at sowing on the early vigor, grain yield and quality of maize

Maize grain yields and profitability are enhanced in temperate growing areas as a result of an early sowing. However, cool conditions may constrain the uptake of nitrogen (N) and phosphorus (P) by the root system during the early and more susceptible growth stages. The application of starter fertilizers near the plant roots could ensure better N and P availability and improve early vigor of the crop. The aim of this study has been to quantify the overall benefits of a localized starter fertilization with N or P, or their combination, on maize (early development, grain yield, grain quality and sanitary traits). A 4-year field experiment was conducted in NW Italy during the 2014–17 growing seasons. The trial compared the sub-surface placement of N, P and NP in bands close to the maize seed furrows, as a starter fertilization strategy, with unfertilized controls on sandy silt loam (SSL), silt loam (SL) and silty clay loam (SCL) soils. These soils were placed side by side, and were characterized by low, high and medium N and plant-available P contents, respectively. The results showed that when N and P were applied together, the early vigor (plant height) and canopy development (NDVI values) of the maize were significantly enhanced, compared to both the controls and to the application of the single elements in all the soils. The positive growth responses to starter NP fertilization were combined with accelerated crop phenological development, so that anthesis occurred 2.4–3.1 days earlier. Thus, the grain yield was enhanced following the NP sub-surface placement (+7%, +15% and +11%, in SSL, SL and SCL, respectively), mainly due to an increase in the number of kernels per ear (+10%), while the grain moisture content was reduced, compared to the controls, in all the soils (−2.2%). The application of N or P alone did not consistently affect either the grain yield or the moisture content in any of the three soils. The starter fertilization strategy also affected both the qualitative and sanitary grain traits. NP and N both resulted in an increase in the grain hardness in the SL and SCL soils, but when P was applied alone, no significant effects were observed. The use of NP starter fertilization significantly reduced the ear injuries caused by European Corn Borer in all three soils (−44%), and reduced ear rot severity in the SSL and SL soils and the fumonisin content (−72%) in the SL and SCL soils, compared to the untreated controls. The synergistic effect of N and P applied as a sub-surface band at sowing had a consistent positive effect on the advancement of the flowering dates at different sites in different years, even in soils that have tested high to P or N. Thus, the application of NP starter fertilizer is a crop practice that should be considered in North Italy and for similar soils and environments.

Influence of Structural Parameters of Intermittent Discharge Equipment on Hole Fertilization Performance

HighlightsIntermittent fertilizer discharge equipment was designed to realize hole fertilizer application.The optimal structure of the fluted discharge roller was three grooves with conical cross-sections.This study provides a reference for the design of equipment and control systems for hole fertilizer application.Abstract. Fertilizers are necessary for high crop yields. In mechanized application of starter fertilizer for tobacco, discharging the fertilizer immediately below the seedlings promotes root growth and nutrient uptake, resulting in a high utilization rate. This placement is called hole fertilizer application and is fertilizer-saving and environment-friendly. To meet the requirements of hole fertilizer application for crops with specific plant spacing, equipment to intermittently discharge fertilizer has been designed based on the structure of a fluted roller. To explore the influence of the structural and working parameters of the intermittent discharge equipment on the uniformity of hole fertilization and the accuracy of marking fertilizer positions, the fertilizer discharge process and marking process were simulated using a discrete element method based on theoretical analysis. The optimal combination of parameters was a tapered circular groove shape with three grooves, the rotational speed of the fluted roller was 30 rpm, and the center distance between two material bins was 40 cm. In the simulation, the coefficient of variation for single-hole fertilizer application was 3.39%, and the marking error was 1.86 cm. Bench tests were performed using the optimal combination of parameters to verify the simulation results. The intermittent discharge equipment was able to achieve hole fertilizer application and mark the fertilizer position. The coefficient of variation for single-hole fertilizer application was 4.35%, and the marking error was 1.95 cm. The bench tests proved that the discrete element method was feasible for optimizing the equipment parameters. This study provides a reference for developing hole fertilizer application equipment and control systems to improve fertilizer use efficiency. Keywords: Fertilizer performance, Groove structure, Hole fertilizer application, Intermittent fertilizer discharge, Structural parameter.s

Development and Performance Evaluation of a Precise Application System for Liquid Starter Fertilizer while Sowing Maize

At present, liquid starter fertilizer (LSF) application technologies experience problems with low fertilizer utilization efficiency. In this study, we adopted a method of precise application of LSF near the seeds on seed bed in point form during sowing. A precise application system that can detect seed information in real time and control the solenoid valve to open automatically was developed for this method. The LSF supply system and detection control system were studied in detail. Field experiments were conducted to evaluate the performance of the precise application system in terms of operation quality (qualified index of the length of the LSF, QIL; the amount of the LSF, FA; and qualified index of the distance between the seeds and the LSF, QID) at forward speeds of 4, 6, and 8 km/h and pressures of 0.10, 0.15, 0.20, 0.25, and 0.30 MPa. The results indicated that QIL was 96.4%, the range of FA was 1.34 to 13.86 mL, and QID was 82.6%, which signifies the developed system meets the demands of precise LSF application. This method achieves the target of improving fertilizer use efficiency and provides a reference for developing fertilization devices for precisely applying LSF.

Effekte einer punktuellen Düngerapplikation in Mais

Improving fertilizer efficiency requires revising established procedures and using new methods and procedures. Therefore, a system for the precise application of fertilizer in maize cultivation was developed and tested in the laboratory and in the field. This technical development was accompanied by manual field trials to test the relevance of this novel application method for crop production. Yield-neutral savings potential of up to 50% of the current starter fertilizer application by the more precise fertilizer application was shown. A significant yield increase (α < 0.05) of 6 to 7% was documented with the same fertilizer input. Based on the results of the agronomic field trials, a method for mechanically applying this precise fertilizer placement method was developed and validated.

The Influence of the Application Technique and Amount of Liquid Starter Fertilizer on Corn Yield

The aim of this research was to study the impact of application technique and rate of liquid starter fertilizer applied with a novel device on the production of corn. Starter fertilizer was applied in the root system range of freshly germinated plants in the ‘belt’ and ‘point’ forms at different quantities (35, 50, 70, and 100 L ha−1), which led to intensive plant growth in the initial stages of development. This adapted system was used for sowing and for application of the liquid starter fertilizer at the same time. The field trial was set up at two sites (two different land types), in the conditions of the natural water regime of the soil during the three vegetation seasons in the period 2016–2018. For this purpose, a prototype of the electronic device EUKU-01 was designed. The starter fertilizer was applied at 5 cm laterally from the row where the sowing was performed and 5 cm below the depth at which the corn seeds were sown. Data were statistically analyzed by two-factor analysis of variance, where the influence of mineral fertilizer treatment and the influence of liquid starter fertilizer treatment were observed as factors. The results showed that the optimal choice of the technique of liquid starter fertilizer application can result in fertilizer savings by 30% without reducing yield.

Corn yield response to sub-surface banded starter fertilizer in the U.S.: A meta-analysis

Abstract Sub-surface fertilizer application at planting (i.e., starter fertilization) is a common practice in U.S. corn (Zea Mays L.) production to improve early-season nutrient uptake, nutrient use efficiency, and plant growth, especially under cool and moist spring soil conditions. However, yield increases from starter applications can vary across production systems and environments. Here, we use a meta-analysis approach to quantify and generalize corn yield responses to sub-surface starter fertilizer applications in the U.S. and to understand the management and environmental factors that drive variability in corn yield response across previously published research. This meta-analysis summarizes peer-reviewed research from the U.S. published between 1990 and 2019. The dataset encompasses 474 observations from 23 studies conducted in various locations and includes information regarding management practices used and soil and weather conditions. We calculated effect size as the natural log of the response ratio, with the response ratio determined as corn yield with a starter fertilizer application containing nitrogen (N) and phosphorus (P) or N, P and potassium (K) relative to corn yield without a starter fertilizer application. Additionally, we investigated the impact of potential moderator variables on corn response to sub-surface starter fertilization (e.g. agronomic practices, soil properties, and weather conditions). On average, fertilizer sub-surface applied in the furrow or banded 5 cm to the side and 5 cm below the seed at planting increased corn yield by 5.2 %. Corn response to starter fertilization was consistent across many agronomic and environmental conditions including different tillage systems, previous crops, soil textures, and planting season weather conditions. Yield benefits decreased with increasing soil test P and K levels. Nevertheless, yield increases from starter fertilization occurred with soil test levels up to 500 % and 300 % of the P and K critical levels, respectively. In addition, corn yield benefits from starter fertilization decreased as corn planting density increased and as corn yield level decreased. Overall, this meta-analysis provides support for the use of sub-surface starter fertilizer applications to improve corn yield.

Kentucky bluegrass and bermudagrass rooting response to humic fertilizers during greenhouse establishment

AbstractGreenhouse research was conducted to examine effects of adding humic products to fertilizers on turfgrass. The objective of this study was to determine if the addition of humic products to fertilizers will increase turfgrass root and shoot morphological parameters. Kentucky bluegrass (KBG; Poa pratensis L.) and bermudagrass [Cynodon dactylon (L.) Pers.] were established in sand‐filled tubes. Treatments included synthetic fertilizer with black gypsum (22N‐0P‐3.3K, 30% gypsum and 4.7% humic acid), polymer‐coated humic‐coated urea (PCHCU; 2% humic acid), urea with humic dispersing granules (HDG; 70% humic acid), starter fertilizer (18N‐10.5P‐10K) with HDG, starter fertilizer, stabilized nitrogen, urea, and a control group. Fertilizers were applied at 48.8 kg N ha−1 and HDG was applied at 44.4 kg ha−1. Starter fertilizer and starter fertilizer with HDG increased KBG total root length (105 and 112%), root biomass (232 and 244%), and shoot biomass (205 and 204%) compared with urea. In KBG, PCHCU and urea with HDG increased total root length (37 and 20%) compared with urea. In bermudagrass, starter fertilizer and starter fertilizer with HDG increased total root length (241 and 248%), root biomass (672 and 707%), and shoot biomass (821 and 808%) relative to urea. Besides treatments with starter fertilizer, no treatments were different from urea for bermudagrass. These results suggest that starter fertilizer application is critical to turfgrass rooting at establishment. Adding humic products to the starter fertilizer did not increase rooting. In the absence of a starter fertilizer, PCHCU and urea with HDG improved KBG total root length compared with urea.

Influence of Phosphorus in Starter Fertilizer on the Establishment of Tall Fescue

Phosphorus (P)-containing starter fertilizers are often recommended for establishing new turf, regardless of P levels indicated by the soil test. However, few field studies have been conducted to determine the effects of P in starter fertilizer on the rate of turf establishment. The primary objective of this study was to determine if P in starter fertilizer enhances tall fescue groundcover and growth during establishment on silt loam soil. This 2-year field study was conducted on silt loam soil tilled with a rototiller or core-aerated and vertically sliced. Mehlich-3 P levels ranged from 38 to 270 mg·kg−1. Experiments were conducted during late summer and fall, and all tests were seeded with ‘Bullseye’ tall fescue (Festuca arundinacea Schreb.). Treatments included 49 and 73.5 kg·ha−1 of nitrogen (N) without P, 49 kg·ha−1 of N plus three different rates of P (24.5, 49, and 73.5 kg·ha−1), and a nonfertilized control. Comparisons between groups that received treatment with 49 kg·ha−1 of N without P and treatments with 49 kg·ha−1 N with P revealed few significant groundcover responses to the addition of P. Of 12 groundcover assessments performed during four experiments, contrasts revealed only one instance of a higher percentage of groundcover in response to the addition of P. This occurred during an experiment having a pretreatment Mehlich-3 P level of 38 mg·kg−1. Comparisons indicated greater clipping yields in response to the addition of P in one of the four experiments. This occurred in soil that was core-aerated and sliced with an initial Mehlich-3 P level of 66 mg·kg−1. In most cases, Mehlich-3 P levels at the end of each experiment increased as the P application rates increased. The only instance in which comparisons between treatment with 49 kg·ha−1 N without P and treatments with 49 kg·ha−1 N with P demonstrated a significant leaf tissue response to P during the experiment with soil that was core-aerated and sliced with a pretreatment Mehlich-3 P level of 66 mg·kg−1. When individual treatments were compared, the 73.5 kg·ha−1 N treatment without P produced similar or higher groundcover and clipping yields than all other treatments during all four experiments. This study revealed few groundcover and variable tall fescue clipping yield responses to P additions when applied at rates used for starter fertilizer applications on silt loam soil during late summer and fall. Groundcover and growth responses due to P in starter fertilizers do not appear to be solely related to soil test P levels, and other factors such as the method of establishment (tilling soil vs. core-aerating and slicing the soil surface), environmental conditions, and the N content of soil may be involved.

Soybean Yield Response to In‐furrow Fungicides, Fertilizers, and Their Combinations

Core Ideas Fungicide in‐furrow and starter fertilzer individually did not increase yield. Fungicide and starter fertilizer combined in‐furrow increased yield marginally. Fungicide and starter fertilizer in‐furrow may not be economical without disease. Planting into cool and wet conditions exposes soybean [Glycine max (L.) Merr.] seed and seedlings to pathogens that may reduce plant populations, resulting in lower yield. Recently, fungicides have been labeled for in‐furrow applications and marketed to provide additional broad‐spectrum protection from soilborne fungi and enhance seedling vigor. Additionally, liquid fertilizers have been promoted recently as a carrier for fungicides to improve yield in some soybean producing areas in the United States. The objective of this study was to evaluate the effect of a fungicide, starter fertilizer, and a combination of fungicide and starter fertilizer on soybean yield. Field experiments were laid out in Arkansas, Indiana, Iowa, and Mississippi in the United States and Ontario, Canada, with a total of 14 site‐years. A positive yield response was observed with the fungicide and starter fertilizer treatment combination in Arkansas in 2014; however, there was no effect of treatment on soybean yield at any other location or year. Overall, a yield benefit of 1.6 bu/acre (107.6 kg/ha) (P = 0.02) with the fungicide and starter fertilizer treatment was observed across all locations when combined using meta‐analysis. In conclusion, our study suggests that the prophylactic application of fungicide and starter fertilizer may not be profitable without the risk of soilborne diseases and nutrient deficiencies.

Effect of Diammonium Phosphate as In‐Furrow Starter Fertilizer on Winter Canola Grain Yield and Quality

Core Ideas In‐furrow application of diammonium phosphate (DAP) as a starter fertilizer could be a beneficial component of a comprehensive soil fertility program for winter canola production. Effect of in‐furrow starter, DAP, on the oil and protein content of winter canola was not significant. It is important to account for both soil test P (STP) and soil pH completely when providing nutrient recommendations in winter canola. Winter canola is a valuable rotational crop in Oklahoma. Starter fertilizer application is viewed as a way to improve canola yields. Field experiments were conducted in Dacoma, El Reno, Fairview, Fort Cobb, Kingfisher, Lahoma, Lamont, Miami, and Perkins, OK to evaluate the effect of applying diammonium phosphate (DAP, 18–46–0: N–P2O5–K2O) in‐furrow on winter canola grain yield and quality. Diammonium phosphate was applied with the seed at planting at 22 and 30 lb/ac in no‐till (NT) and minimum/conventional till (CT) systems, respectively. Canola variety ‘DKW 46–15’ was seeded from September 10 to October 10, 2016 at 3.75 lbs/ac spaced at 7.5 (CT) and 15 in (NT). Four of the 10 locations responded to in‐furrow application of DAP. Yield response ranged from 1 to 6 bu/ac. Locations that had low soil test phosphorus and low soil pH generally had higher yield response (3–6 bu/ac) than all other locations. Effect of in‐furrow DAP on the oil and protein content of winter canola was not significant. Results indicated the importance of accounting for both soil test phosphorus and soil pH completely when providing nutrient recommendations in winter canola.

Starter Fertilizer for Managing Cover Crop‐Based Organic Corn

Core Ideas Grass and legume cover crops are combined for weed and fertility management. A cereal rye and hairy vetch mixture provided more than 7500 kg ha−1 biomass. Additional fertility is necessary to maximize cover‐crop based organic corn yield. Subsurface banding feather meal is an option to increase organic corn yield. If cover crop biomass is low, providing adequate N fertility is critical for yield. Grass and legume cover crops are combined in mixtures to provide both weed and N fertility management in organic production; however, additional N fertility may be required to maximize corn yield. The research was conducted in Beltsville, MD; Kinston, NC; and Salisbury, NC; from 2012 to 2014 to evaluate the effect of starter fertilizer source and application method on weed competition and grain yield in cover crop‐based, organic corn production. Fertility treatments included high rate broadcast poultry litter (Plant available nitrogen [PAN] = 160 kg ha−1), low rate broadcast poultry litter (PAN = 72 kg ha−1), subsurface banded feather meal (PAN = 80 kg ha−1), subsurface banded poultry litter (PAN = 12 kg ha−1), and no starter fertility. A cereal rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) mixture was established in the fall and was terminated using a roller‐crimper before corn planting. Cover crop biomass more than 7500 kg ha−1 provided excellent weed suppression. In a combined analysis of five environments, corn N content and yield followed the same pattern of high rate broadcast poultry litter &gt; low rate broadcast poultry litter = subsurface banded feather meal &gt; subsurface banded poultry litter = no starter fertility. Results from this study indicate that starter fertilizer is necessary to maximize corn yield in cover crop‐based organic corn production and that decisions regarding additional fertility will need to be dynamic based on site history, cover crop biomass production, and the ability to broadcast poultry litter.

Impact of Starter Fertilizer on Cotton Growth, Development, Lint Yield, and Fiber Quality Production for an Early Planted No‐Till System

Improved yield potentials occur when planting cotton (Gossypium hirsutum L.) early, but cool conditions associated with early planting can hamper seedling growth. Starter fertilizers could be a source of P for seedling growth under cool conditions due to reduced soil P mineralization. The objective was to document how cotton cultivars responded to starter fertilizer application when planted early in a no-till production system. Seven cultivars were grown no-till during 2008 through 2010. Plots received an in-furrow starter fertilizer application or were untreated. Dry matter partitioning, light interception, lint yield, and fiber quality data were collected. Stands were reduced 20% by the starter fertilizer. Few growth differences were detected by treated and untreated plots although the starter fertilizer did elicit a single 17% increase in the blooming rate at 90 days after planting in 2009. Despite the lack of growth differences and the reduced stands, starter fertilizer increased yields 4% in 2 of the 3 yr. Few consistent fiber quality differences were detected between the fertility treatments. Starter fertilizer application can produce a modest yield improvement when used in an early planting no-till cotton production system. Producers must decide whether this modest yield boost is economically sufficient to justify the additional input costs.

Organic and Inorganic Blended Materials for Use as Pop-Up Fertilizer for Cotton Seedlings

Various factors such as soil moisture at planting, application rate, and composition of the fertilizer materials have contributed to the erratic results from use of starter and “pop-up” fertilizers. Earlier research with ammonium polyphosphate (11–37–0) has shown some beneficial effects on growth and lint yield of cotton (Gossypium hirsutum L.) when the starter was placed in the seed furrow or surface banded at time of planting. The purpose of this research was to determine the effect of starter fertilizer composition and application rates on cotton seedling emergence and early shoot/root growth at low and medium soil moisture regimes at planting. Treatments consisted of a control (0–0–0), 7–21–0, 5–15–0, and 3–9–0 liquid blends applied directly in the seed row at 3, 6, and 9 acre−1 to an Orelia sandy clay loam. The three blends contained 2.4%, 1.4%, and 1.0% by weight organic extract, respectively, and used ammonium orthophosphate as sole source of P. Standard-grade ammonium polyphosphate (11–37–0) was used for comparison at rates of 3 and 6 gal acre−1. The randomized complete block (RCB) experiment was conducted in the greenhouse for 35 days after planting (DAP). All pop-up fertilizers had a definite effect on cotton seedling emergence and early growth. Ammonium polyphosphate caused a marked delay in emergence even at 3 gal acre−1 during the first five days. Pop-up mix 3–9–0, at 6 and 9 gal acre−1, showed significantly less damage than other blends as well as the 11–37–0. At 11 DAP and adequate soil moisture, no difference among blends was observed but blended pop-up fertilizers had significantly greater (P < 0.05) emergence than 11–37–0, which produced only 30% emergence at 6 gal acre−1. Chlorophyll readings were only slightly greater for pop-up blends containing organic acids. Seedlings grown under less soil moisture showed a gradual decrease in plant height as pop-up rates increased whereas no effect was measured at adequate soil moisture. Fertilizer blends failed to increase final dry-matter yields of seedlings at 35 DAP when compared to the control whereas 11–37–0 decreased growth at certain rates. Where adverse effects from pop-up fertilizer treatments occurred, they were magnified by less soil moisture. Further research under field conditions is needed.

Survey of nitrogen fertilizer use on corn in Minnesota

A survey was conducted in the spring of 2010 to characterize the use of nitrogen (N) fertilizer on corn (Zea mays L.) by Minnesota farmers in the 2009 growing season. Detailed information on synthetic N fertilizer management practices was collected from interviews with 1496 farmers distributed across all of the corn growing regions in the state. The total amount of corn they grew represented 6.8% of the ha of corn harvested in Minnesota in 2009. This report summarizes data on: (1) N fertilizer rates, (2) major N sources (excluding manures), (3) application timing of the major N source, (4) use of nitrification inhibitors, additives, and specialty N fertilizer formulations, (5) fertilizer placement and incorporation practices, (6) use of starter fertilizer, split and sidedress applications, and other N sources such as ammonium phosphates, (7) N fertilization of irrigated corn, and (8) use of soil testing as a fertility management tool. Many of the survey results are reported as statewide averages, but where regional differences occurred the data are broken down and presented separately for different parts of the state. This survey provides the most comprehensive set of data on N fertilizer use on corn that has been collected in Minnesota. The information can be used to target research and education programs to improve N management for both production and environmental goals. The statewide average N fertilizer rate was 157kgNha−1. Variable rate application was used to apply N by 23% of farmers. About 59% of surveyed farmers applied the majority of their N fertilizer in the spring before planting, 32.5% made their main N application in the fall, and 9% sidedressed the majority of their N after corn emergence. Most farmers used anhydrous ammonia (46%) or urea (45%) as their major source of N fertilizer, while 6.5% used a liquid N formulation as their primary N source. Soil testing was used as a fertility management tool on 84% of the surveyed fields in the last 5years. Overall results indicate that N fertilizer use by Minnesota corn farmers is generally consistent with University of Minnesota Extension N management guidelines. Fertilizer N use could probably be improved by taking adequate N credit for previous soybean crops. In the South Central region of the state, fertilizer N recovery could potentially be improved by increased use of nitrification inhibitors with fall-applied anhydrous ammonia or by delaying anhydrous ammonia application until spring.

Corn Responses to In‐Furrow Phosphorus and Potassium Starter Fertilizer Applications

Starter N–P or N–P–K fertilizers often are applied to corn (Zea mays L.), but questions arise concerning the usefulness of starter K. This study assessed responses of corn grain yield, early growth, and early P and K concentration and uptake to in‐furrow fluid P–K and K starter fertilizers. Six replicated small‐plot trials evaluated a control receiving no P or K, 3–8–15 (N–P–K) starter at 5 to 7 kg P ha−1 and 10 to 14 kg K ha−1, 0–0–25 (N–P–K) starter at 10 to 14 kg K ha−1; broadcast fertilizer at 49 to 66 kg P ha−1 and 112 to 140 kg K ha−1; and broadcast‐starter combinations. More N (191–224 kg ha−1) was applied uniformly. Eight replicated field‐length strip‐trials evaluated 0–0–25 starter at 10 to 14 kg K ha−1, broadcast fertilizer at 112 kg K ha−1, and broadcast plus starter. More N (168–224 kg ha−1) and P (49–66 kg ha−1) were applied uniformly. The fields encompassed various tillage systems, hybrids, soils, and soil‐test levels. Starter P‐K applied in addition to broadcast P‐K increased growth and P and K uptake compared with broadcast P–K at two trials, but did not increase yield. Starter K applied in addition to broadcast P–K at the small‐plot trials or broadcast K at the strip‐trials did not increase growth compared with broadcast fertilization, decreased K uptake at 2 of the 14 trials, and did not affect yield. Potassium seldom had a starter effect on corn. Starter K may not increase corn early growth or yield unless the soil is deficient in K and broadcast K is not applied.

Yield response to fertilization strategies in no-tillage soybean, corn and common bean crops

Two research fields were conducted on a Haplohumox from 1998 and to 2005. The study aimed to evaluate the strategies for starter fertilizer application on corn, soybean and common bean yield as well as the accumulation of earlier dry matter for corn in a no-tillage crop rotation system in south of Brazil. There was no increase in the yield of soybean with phosphorus and potassium application for at least seven seasons, while corn and common bean showed increased yields with phosphorus, potassium and nitrogen application. For soybean, corn and common beans in no-tillage systems with high levels of phosphorus and medium of potassium, the starter fertilizer can be applied in any of the methods evaluated and in any of the period considered. The presence or absence of potassium in the furrow, phosphorus sources and row preparation components provided similar yields to corn, soybean and common bean.