Increase In Corn Yield Research Articles

Economic and Financial Viability of Residue Management: An Application to the Texas High Plains

Costs and benefits of no-tillage (NT) were analyzed and compared with conventional tillage (CT) for irrigated corn (Zea mays L.) in the northern Texas High Plains. Research results, from a 4-yr wheat (Triticum aestivum L.)/corn/fallow rotation, were used to validate the Erosion Productivity Impact Calculator (EPIC), a widely used daily time-step hydrologic and crop growth simulator. The yields generated by EPIC were used in the Farm Level Income and Policy Simulation Model (FLIPSIM), to analyze the long-term (10 yr) economics of NT and CT corn production on a whole farm basis under various irrigation strategies. The results indicated that NT increased the probability of survival for the low water irrigation strategy while increasing net cash farm income by 8,5% on the more frequent irrigations strategy. NT resulted in higher present values of ending net worth for all irrigation strategies. NT's ability to reduce water needs, decrease yield variability, and reduce machinery use (fuel, replacement, and repair costs) more than offset the increase in chemical costs associated with NT compared with CT. Research Question Economic impacts of residue management on Great Plains farmers producing irrigated crops were largely unknown when the Food Security Act of 1985 mandated that participants in farm programs who farm highly erodible cropland must implement SCS approved soil conservation farm plans by January 1995. The mandate was intended to reduce soil erosion, both by wind and water. While dryland crop production in the Great Plains often results in inadequate residue for erosion control, irrigation generally produces adequate residue for soil protection if properly managed. The threat of losing farm program benefits is a concern to both dryland and irrigated producers. The purpose of this research is to quantify the economic benefits (costs) of producing no-tillage (NT) corn for a representative feed grain farm in the northern Texas High Plains. Literature Summary Conservation tillage research in the Great Plains dates back to the 1930s. Early research investigated dryland benefits of residue management during nonuse periods, or fallow, primarily for enhancing soil water storage and reducing crop yield variability. Past research has found that NT practices increase yields proportionally more under dryland conditions than under irrigated conditions. Previous studies have also shown that furrow erosion can be reduced with NT practices, which may reduce seed bed preparation time and costs in subsequent years. Economic impacts of residue management are both short term and long term, depending largely on the immediate increase in herbicide expenses, which substitute for short-run costs of tillage, and the reduction in long-term equipment depreciation costs. Study Description Field research data is used to validate the Erosion Productivity Impact Calculator (EPIC), a widely used daily time-step hydrologic and crop growth simulator. EPIC is then used to develop long-term and stochastic corn yields for NT and conventional tillage (CT) under alternative irrigation scenarios for a representative northern Texas High Plains feed grain farm producing NT and CT corn. The stochastic yields for CT and NT corn generated by EPIC given alternative irrigation strategies are used as input into FLIPSIM. The financial outcomes of the farm for the CT and NT systems are compared to determine their impacts on the farm's long-run economic viability under alternative irrigation scenarios. Applied Questions How does NT compare with CT economically? The results of the 10-yr whole farm financial analysis indicated that NT was more profitable than CT. A reduction in expenses was the largest benefit gained from NT. The reductions included repair costs, fuel costs, irrigation costs, interest, and machinery replacement. While initial machinery debt was increased, the increase in net cash farm income and the longer useful life for machinery allowed NT to service debt faster than CT, thus decreasing interest expenses. How do the effects of NT vs. CT differ under alternative irrigation strategies? Corn yield increases and cost reduction benefits using NT are greatest for the limited water scenarios. This leads to greater increases in net cash farm income and equity growth. As the irrigation amounts increase, the need for NT as a source for maintaining soil moisture diminishes and thus NT yield benefits are diminished relative to CT at higher irrigation level.

Soil Water, Plant Growth, and Yield of Strip-Intercropped Corn

Strip-intercropping soybean (Medicago sativa L.) with corn (Zea mays L.) decreases yields in soybean border rows. Separating corn and soybean with a small grain strip could decrease competition for soybean and improve overall yield. This study was conducted to determine the effect of a small grain strip on corn and soybean performance and on soil water content in the corn strip. Corn and soybean were strip-intercropped (rows running north-south) with oat (Avena sativa L.) in 1991 and barley (Hordeum vulgare L. emend. Lam.) in 1992 on a ridge-tilled Dalhousie silt loam (fine, mixed, mesic Typic Endoaquoll) in Nepean, Ontario. Both years, plant height varied among corn rows [...]

Crop and Tillage Rotations: Grain Yield, Residue Cover, and Soil Water

AbstractInformation regarding crop yield response for different tillage and rotation systems is needed to determine regional or local suitability for a given production system. Our objective was to determine the effects of continuous and alternating tillage sequences in corn (Zea mays L.) monoculture and corn‐soybean [Glycine max (L.) Merr.] rotation on residue cover, soil water, and grain yield. Continuous conventional tillage (CT), continuous no‐tillage (NT), or CT and NT alternating every other year were evaluated during a 5‐yr period on a Rion (fine‐loamy, mixed, thermic Typic Hapludult)‐Pacolet (clayey, kaolinitic, thermic Typic Kanhapludult) sandy clay loam complex at a Piedmont location and an Eunola sandy loam (fine‐loamy, siliceous, thermic Aquic Hapludult) at a Coastal Plain location. The 5‐yr average NT corn grain yield was 27% (1.15 Mg ha−1) higher than CT at the Piedmont location, but only 4% (0.32 Mg ha−1) higher at the Coastal Plain location. Continuous NT at the Piedmont location also resulted in higher corn yields 2 out of 4 yr compared with NT following CT. The increase in corn yield with NT was associated with greater soil water availability, primarily attributed to surface residue cover from corn stover fostering greater infiltration on a crust‐prone soil. Soybean yield during the 5‐yr period was 5% higher with NT at the Piedmont location and unaffected by tillage at the Coastal Plain location. In general, crop rotation had no effect on corn yield at either location. Results indicate that continuous NT should be the system of choice on this upland Piedmont soil.

Topsoil Depth, Fertility, Water Management, and Weather Influences on Yield

AbstractThe productive capacity of a soil is generally related to topsoil depth. This study was conducted to determine the influence of topsoil depth, soil fertility, and water management on grain yield for corn (Zea mays L.) and soybean (Glycine max [L.] Merr.). A field experiment at Columbia, MO, was initiated in 1983 and maintained through 1987 on a Mexico silt loam (fine, montmorillonitic, mesic Udolic Ochraqualf). The study was conducted using a split‐plot experiment for each crop. Main effects included topsoil (depth to claypan), soil fertility, and water management. Desurfaced plots were constructed having topsoil depths of 0, 125, 250, and 375 mm. Plots were either fertilized according to soil‐test recommendations or unfertilized. Water management was either rain fed or with supplemental irrigation. Overall, corn yield was 5.7 times more sensitive than soybean to topsoil depth when averaged over both fertility and water management. The topsoil × soil fertility interaction was characterized by a 34% reduction in corn yield with topsoil depths < 125 mm in the fertilized treatments when averaged across water management. Similar yield reductions for unfertilized plots were observed but were linearly related to topsoil depth. The fertility × irrigation interaction described a multiplicative increase in corn yield when corn was both fertilized and irrigated. Only topsoil depth and water management significantly influenced overall soybean yield.

Nitrogen Management and Interseeding Effects on Irrigated Corn and Sorghum and on Soil Strength1

AbstractA 15‐yr experiment on Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudolls) investigated N management effects on corn (Zea mays L.) and grain sorghum [Sorghum bicolor (L.) Moench] grown side by side, under identical furrow‐irrigated conditions. Included were comparisons of anhydrous ammonia (AA) and N solution (UAN) as N sources, planting time (UAN‐PL) vs. summer sidedressing (UAN‐SD) application of the N, and rates of 90,180, and 270 kg N ha−1. Additionally, interseeding of rye (Secale cereale L.) into high N plots and alfalfa (Medicago sativa L.) into check plots of corn was accomplished at the time of ridging for furrow irrigation. The objectives were to evaluate the long term effects of varied management of the two N carriers and the interseedings on grain yields and N utilization, and the relative effects of these treatments on soil strength. Grain sorghum was the more productive crop under conditions of low N availability while corn responded to higher N rates, becoming the more economic crop with yields approaching 10 Mg ha−1 when N was plentiful. Yield increases averaged 5% greater for UAN‐SD over UAN‐PL, and AA was slightly more effective than UAN‐SD for both crops. Interseeded alfalfa and rye green manures provided average corn yield increases of 880 and 585 kg ha−1, respectively, explainable in part by improved N economy. No significant differences in penetrometer or vane shear tests were found between soils from AA and UAN‐SD plots, although there was a tendency toward lower soil‐strength values with both N carriers, relative to check plots.

Climatic Change, Weather Variability, and Corn Production1

AbstractA crop/weather model was used to determine the impact of changes in climate and weather variability on corn (Zea mays L.) production from 1891 to 1983. Five Corn Belt states, Illinois, Indiana, Iowa, Missouri, and Ohio, were included in the study. These states produce over 50% of the U.S. corn crop. A cooling trend from 1930 to 1972 was accompanied by increasing rainfall in July and August, and by decreasing weather variability. These three factors were favorable for corn yield increase. Simulated corn yields, calculated from weather data, increased 970 kg ha−1 from 1930 to 1972 because of improved weather for corn. After 1972 there was greater weather variability and higher intensity rainfall events. Fertilizer use on corn increased substantially in the 1960s and increased at slower rate after 1972. The annual increase in corn yield with normal weather after 1972 was less than half as much as it was from 1960 to 1972. Highest yields of corn have been associated with normal preseason precipitation, normal June temperature, below normal temperature in July and August, and above normal rainfall in July and August. The period after 1970 was expected to warm but weather variability has masked the identification of a trend.

Water Management of Corn and Soybeans on a Claypan Soil

ABSTRACT A water management study for corn and soybeans was conducted on a claypan soil in south central Illinois to determine yield response to irrigation and drainage. The study investigated all possible combinations of four drainage methods under both sprinkler irrigation and nonirrigated conditions. Over the seven year period of the experiment, average annual corn yield increases were 3.9 t/ha for irrigation and up to 1.8 t/ha for drainage. A synergistic yield increase of up to 5.0 t/ha for corn was present. Soybeans were less responsive to either irrigation or drainage over a 4-yr period with average annual yield increases of 0.4 t/ha for both practices. A synergistic yield increase of up to 0.7 t/ha for soybean was produced over the 4-yr period.

Continuous Tillage and Rotation Combinations Effects on Corn, Soybean, and Oat Yields1

AbstractFew studies report long‐term effects of various tillage and crop rotation practices. Studies were conducted to compare the relative ability of various tillage and crop rotation combinations (3 ✕ 3 factorial) to sustain corn (Zea mays L.), soybean (Glycine max L.), and oat (Avena sativa L.) yields. The tillage and rotation combinations were continuously applied for more than 20 years to a well‐drained Wooster silt loam (fine‐loamy, mixed, mesic Typic Fragiudalf), an imperfectly drained Crosby silt loam (fine, mixed, mesic Aeric Ochraqualf), and a very poorly drained Hoytville silty clay loam (fine, illitic, mesic Mollic Ochraqualf). Tillage treatments were no‐tillage; plow and then plant; and plow, disk, and plant. Rotation treatments on the Wooster and Hoytville soils included continuous corn, corn and soybean in a 2‐year rotation, and corn‐oats‐meadow in a 3‐year rotation. Only continuous corn was grown on the Crosby soil. Corn yields were always positively influenced by no‐tillage on the Wooster soil and negatively influenced on the Hoytville soil. The results obtained for the Crosby soil were mixed. The average yearly corn yield increase and decrease due to no‐tillage on the Wooster and the Hoytville soils were 1070 kg ha−1 and 503 kg ha−1, respectively. The negative response to no‐tillage on the Hoytville soil was primarily due to the large decrease in yield obtained as a result of the continuous corn rotation treatment (average annual yield decrease, 880 kg ha−1). Yield responses of soybean and oats on the Wooster and the Hoytville soils were similar to those observed for corn. When Phytophthora root rot resistant (tolerant) soybean cultivars were grown on the Hoytville soil with the standard cultivars which had been used during most of the experimental period, yield differences between the no‐tillage and plow treatments were essentially eliminated. This study suggests that yield reductions of corn and soybean associated with no‐tillage on heavy clay, very poorly drained soils may be reduced by rotating crops and/or by the use of disease resistant cultivars.

Nitrification Inhibition by Nitrapyrin and Volatile Sulfur Compounds

AbstractNitrification inhibitors can slow the rate of nitrification in soils and reduce nitrogen losses under some soil‐climatic conditions. Carbon disulfide (CS2) and compounds which produce CS2 have slowed nitrification in laboratory studies, but these compounds have not been tested extensively in the field. Therefore, field studies were conducted on irrigated corn (Zea mays L.) in 1978 and 1979 to evaluate inhibition of nitrification by CS2 at 5.6, 11 and 22 kg ha−1, sodium trithiocarbonate (STC) at 11 and 22 kg ha−1, ammonium dithiocarbamate (ADTC) at 11 and 22 kg ha−1, and potassium ethyl xanthate (KEtX) at 5.6 and 11 kg ha−1 as compared to nitrapyrin (2‐chloro‐6‐(trichloromethyl)‐pyridine) at 5.6 kg ha−1. Anhydrous ammonia was knifed 15 to 20 cm deep on 60 cm spacings at rates of 84, 168, and 252 kg N ha−1. All materials were evaluated on a Eudora fine sandy loam (Fluventic Hapludoll, coarse, silty mesic) in 1979 and CS2 and STC were evaluated on the same soil in 1978 and on two additional soils in 1979: a Pratt loamy fine sand (Psammentic Haplustalf, sandy, mixed, mesic) and a Crete silty loam (Pachic Argiustoll, fine, montmorillonitic, mesic). The performance of STC and CS2 in 1978 and 1979 indicated that these materials were not effective in inhibiting nitrification under the conditions that existed at the locations where they were applied. ADTC and KEtX were not effective inhibitors of nitrification, although they were only tested at one location in 1979. Nitrapyrin was effective in inhibiting nitrification in all studies. However, it resulted in an increase in corn yield only once—the fall N application on the Pratt loamy fine sand. The lack of yield response was attributed to the absence of conditions conducive for losses of nitrate nitrogen.

Tillage Effects on Crop Yield in Coastal Plain Soils

ABSTRACT CORN {Zea mays L.) and soybean [Glycine max (L.) Merr.] were grown on an 18-ha site of Coastal Plain soils under nonirrigated and irrigated conditions for the three-year period, 1979-81. The five tillage treatments were double disking and minimum tillage, both with and without in-row subsoiling at planting; and disking with uniform chisel plowing. Rainfall during the growing season was near normal in 1979, below normal in 1981, and much below normal in 1980. There were significant yield differences due to tillage and irrigation for both corn and soybean. Corn yield increases due to deep tillage were greater in magnitude and were more consistent than those for soybean. Minimum tillage without subsoiling produced the lowest yields for both corn and soybean; however, this treatment had the poorest stand and the most severe weed competition of all treatments. Deep tillage and irrigation produced additive yield increases for corn, but not for soybean, indicating the possible need to use both management practices for corn in some soil conditions. Irrigation increased yields for both corn and soybean across all tillage treatments with mean yield increases of 3.37 t/ha (86%) and 0.73 t/ha (51%) for corn and soybean, respectively. The choice of management practices will depend upon their cost relative to their respective yield increase potential.

Technology and U.S. Corn Yields: Plateaus and Price Responsiveness

Corn yields in the United States have increased at a slower rate during the 1970s than in the previous two decades. Fitting straight lines to aggregate corn yields over the period 1954-80 (figure 1) suggests a curvilinear relationship. Different slopes are obtained by splitting the sample at any one of the years 1969, 1970, 1971. For the split shown in figure 1, the slope is 2.67 for 1954-70 and 1.34 for 197180. Since 1970, events have caused corn yields to drop--the 1970 corn blight, drought in 1974 and 1980, and drops in nitrogen application rates in 1974 and 1975. Whether the slowdown in corn yield increases is temporary, permanent, or signals a plateauing of U.S. corn yields is not clear (Swanson and Nyankori). To analyze this issue, the recent historical data (1954-80) on U.S. corn yields is examined. Swanson cautioned against extrapolating past trends into the future without decomposing technology into its components. Multicollinearity problems dictate a limited decomposition into nitrogen and nonnitrogen components. The basis for this distinction is found in microagronomic data. A second objective is to check whether developments over the last decade have significantly changed the elasticity of U.S. corn yields with respect to the fertilizer-corn price ratio.

Yield Response of Corn and Soybeans to Irrigation and Drainage on a Claypan Soil

ABSTRACT FIVE yr of corn and 2 yr of soybean yield data from forty field plots with combinations of irrigation and drainage treatments are presented. The irrigation treat-ments were sprinkler, furrow, and no irrigation. The drainage treatments were surface, subsurface, surface plus subsurface, and no drainage. The plots were located on a claypan soil in south cen-tral Illinois. Sprinkler irrigation was provided with a solid set system. Furrow irrigation was done with gated pipes. The plots with surface drainage had a slope of 0.5 percent; the others were graded level. Subsurface drainage was provided with plastic tubing on 6 m centers. The data indicate average corn yield increases of 0.8 and 2.4 t/ha due to drainage and irrigation, respectively. Together, irrigation and drainage act synergistically to produce an average yield increase of 4.8 t/ha.

A FIELD COMPARISON STUDY OF AMMONIUM PHOSPHATES AND SUPERPHOSPHATE–UREA OR AMMONIUM NITRATE ON CORN (ZEA MAYS L.) GROWTH IN FIVE QUEBEC SOILS

Effects of mono-, diammonium, and superphosphate with added urea or ammonium nitrate on corn (Zea mays L.) growth were studied in the field in 1971 and 1972. At the rate of 100 kg P2O5/ha, none of the carriers affected emergence of seedlings in five Quebec soils. Leaf P content at silking time was of little benefit in predicting P status of the plants, or in differentiating among the carriers. Phosphorous applications gave significant corn yield increases, with carriers performing alike when averaged over all sites. However, some yield differences among carriers occurred on some soil types and seasons. These carrier differences were not consistent and remain to be clarified. The ammonium phosphates compared with the check generally hastened maturity but reduced potassium levels in leaf tissue of corn.