Soybean Sudden Death Syndrome Influenced by Macronutrient Fertility on Irrigated Soybean in a Corn/Soybean Rotation

The effects of nitrogen (N), phosphorus (P), and potassium (K) fertilization on a corn/ soybean cropping sequence were evaluated from 1983 to 2014, with corn planted in odd years. We observed a relationship between the P rate applied during the corn years and the severity of sudden death syndrome (SDS) in 2014 soybean

Fertilizer Placement and Tillage Interaction in Corn and Soybean Production

Different tillage systems can affect the availability of phosphorus (P) by changing the soil environment. The objective of this study was to evaluate the effects and interaction of fertilizer placement, tillage, and varieties for soybean and corn. The experiment was established at two locations in Kansas in 2014. The experimental design was a factorial in a randomized complete block with four replications. Three fertilizer treatments were combined with two tillage systems and two varieties of soybean and corn selected based on contrasting root systems. Plant tissue samples were collected during the vegetative and reproductive stages to evaluate P concentration, P uptake, and dry matter. Significant differences were found in the parameters across locations for corn and soybean. Results suggest advantages for deep-band application for soybean and broadcast application for corn. Varieties responded differently in the parameters evaluated in this study

Evaluation of Secondary and Micronutrients for Soybean Production in Kansas

Study of secondary and micronutrients is growing because of their potential contribution to yield increases. The objective of this study was to evaluate soybean response to secondary and micronutrient fertilizer application to maximize yields. A randomized complete block design was employed with four replications at five locations during 2013 and five locations in 2014. Treatments consisted of an unfertilized control; micronutrient fertilizer as individual nutrients for boron, copper, manganese, sulfur, and zinc; and a mix of these nutrients using two different placements (dry broadcast and liquid band). Soil samples were collected prior to planting and after harvest. Soybean trifoliates were collected at R2–R3 growth stage and analyzed for the micronutrients evaluated in this study. At harvest, nutrient concentration was analyzed in the seed, and yield was calculated at 13% moisture. No significant difference was found in yields between treatments by location or across locations. Results from tissue and grain analysis showed significant treatment effects on zinc concentrations across locations

Evaluation of Long-Term Phosphorus Fertilizer Placement Effect on Soil Phosphorus and Crop Yield

Phosphorus (P) accumulation in soil with long-term P fertilizer placements can result in a potentially large available reserve of this nutrient for subsequent crop production. This study investigated the effect of phosphorus fertilizer management (placement: broadcast versus deep band) after ten years on soil P, and yield response of crop rotation. Field studies were conducted for a period of ten years in Manhattan, KS. Three treatments were evaluated: 1) control with no P fertilizer application and two fertilizer treatments (80 lb P2O5/a); 2) surface broadcast; and 3) deep band at approximately 4- to 6-in. depth. All treatments received strip-tillage. After ten years, soil samples were collected from the row at two sampling depths (0–3 and 3–6 in.), and the soil P and grain yield of 2015 were evaluated. The accumulation of large amounts of soil P was directly affected by P fertilizer placement. The broadcast P fertilizer placement increased the soil P by the resin method in the topsoil (0–3 in.) and deep band in the subsoil (3–6 in.). Broadcast and deep band placements had the same effect on grain yield of corn and soybean, however, the deep band showed an average lower grain yield for wheat than broadcast

Evaluating the Effectiveness of Iron Chelates in Managing Iron Deficiency Chlorosis in Grain Sorghum

Grain sorghum production in alkaline or calcareous soils is frequently affected by iron (Fe) chlorosis. Soil conditions such as high pH, high free calcium carbonate (lime), and low organic matter favor development of Fe deficiency chlorosis (IDC), which can delay crop maturity and reduce yields. Field experiments were conducted in the summer of 2014 and 2015 to determine the effectiveness of Fe chelate application in alleviating IDC in grain sorghum. Treatments were four Fe chelate application rates (0, 3, 6, and 9 lb product/a) applied either in-furrow with the seed at the time of planting or 2 weeks after planting in 2014. A split treatment of 3 lb/a applied at planting and another 3 lb/a applied 2 weeks after planting was included. The study in 2015 had four Fe chelate rates (0, 3, and 6 lb product/a, and split treatment of 3 lb/a applied at planting and another 3 lb/a applied 2 weeks after planting) as main plots and five commercial sorghum hybrids as sub-plots. Results in 2014 showed IDC scores among the treatments were significant only in the early stages of growth. Iron chelate application did improve sorghum yield, with the highest yield occurring when Fe chelate was split-applied at 6 lb product/a. Grain sorghum hybrids differed in their response to IDC in 2015. Application of Fe chelates suppressed IDC and increased grain yield, particularly in susceptible hybrids in both dryland and irrigated sites. Our findings indicate that sorghum hybrids 86G32 and 87P06 showed promise for tolerance to IDC and that Fe chelate application to reduce IDC is economically feasible at current grain prices

Adversarial Service Networks: A Study of Service Firms’ Response to Manufacturer-led Servitization in Aviation

This study examines the adversarial dynamics that emerge when service firms assess that manufacturers’ servitization initiatives pose an existential risk to their survival as independent organizations. Adopting an industrial networks perspective, this investigation explores how service firms respond to manufacturers’ servitization initiatives that threaten to disintermediate them. The study explores how Maintenance, Repair, and Overhaul firms (MROs) in the aviation industry respond to servitization initiated by Original Equipment Manufacturing firms (OEMs). Empirically, interviews with 49 experienced managers were conducted in the service network to understand their strategic pathways. Their responses reveal that MROs can resist servitization by strengthening their relationships with airlines or developing service-led advanced services. Alternatively, MROs can support OEMs’ servitization by becoming subcontractors or licensed resource integrators. This study shows that servitization depends on the orchestration of service network actors with differing interests, making it contingent and multilateral

Grain Sorghum Response to Band Applied Zinc Fertilizer

Zinc (Zn) is one of the micronutrients found to be deficient in Kansas. The objective of this study was to evaluate the response of grain sorghum to Zn fertilization using strip trials. The experiment was set up in Manhattan, KS, in 2015. The experimental design consisted of two strips, one with Zn fertilizer and the other without, with five replications. Zn fertilizer was applied as starter in combination with ammonium polyphosphate at the rate of 0.5 lb Zn/a. Plant tissue samples were collected to determine Zn content. Grain yield was recorded by combine equipped with yield monitor. No significant differences were found for sorghum grain yield. Grain Zn content increased with Zn fertilization. Zn fertilization may be considered for future studies in food biofortification

Subsurface Drip Nitrogen Fertigation of Corn

The efficient management of nitrogen (N) fertilizer and irrigation is of utmost importance because they are two of the greatest expenses for corn production. This project was conducted to determine if yield and efficiency of fertilizer N in corn could be improved by applying N at later developmental stages through a subsurface drip irrigation (SDI) system. Experiments in 2014 and 2015 compared a Preplant Surface application that injected fertilizer in bands below the residue at planting, to four versions of SDI fertigation that differed in timing and total amount of N applied. The SDI Sidedress treatment concluded at corn tassel stage (VT). The SDI Maximum treatment supplied an additional 40 lb N/a through corn blister stage (R2). The SDI Sensor treatment received N fertigations after corn V10 stage only if the ratio of the SPAD readings from SDI Sensor plots to Reference plots was less than 95%. The Reference treatment received both the surface band injections and all SDI fertigations for total seasonal N application that far exceeded crop N requirements. The Reference treatment produced up to 32 bu/a more grain than the Preplant Surface treatment, but produced an average of 0.7 bushels of grain per pound of N fertilizer. The SDI Maximum treatment averaged only slightly less grain yield than the reference treatment but produced 1.15 bushels of grain per pound of N fertilizer on average. The SDI Sidedress and SDI Sensor treatments resulted in similar yields that averaged 16 bu/a more than the Preplant Surface treatment. The SDI Sidedress treatment used fertilizer N the most efficiently, producing 1.3 bushels of grain per pound of N fertilizer. Applying N into the reproductive stages of corn increased yield, but N fertilizer was used most efficiently when N applications were completed by VT. Although using the sensor to determine later N applications reduced fertilizer input slightly compared to a maximum fertilizer approach, yields were reduced enough to result in similar efficiency of fertilizer use

Kansas Fertilizer Research 2020

A summary of research conducted in 2018-2020 on fertilizer use and management practices for crops in Kansas. Published in 2020 from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service https://www.ag.k-state.edu/