Yr Of Corn Research Articles

Agroecosystem management responses to Haney soil health test in the southeastern United States

AbstractQuantifying the impacts of agricultural management on soil health is critical for making informed sustainable management decisions as soil resources inevitably undergo alterations due to management. One recently popular and soil biology–based method of soil health assessment is the Haney Soil Health Test (HSHT), whose most recent version is known as the “soil health tool”, attempts to integrate soil health and fertility. Comprehensive evaluation of the HSHT and its underlying indicators in different agroecological regions is currently lacking. This study therefore evaluates the HSHT on three ongoing field experiments in southeastern United States: (a) 39 yr of continuous soybean [Glycine max (L.) Merr.] with different tillage treatments, (b) 4 yr of corn (Zea mays L.)–soybean rotation with different cover crop treatments, and (c) 37 yr of continuous cotton (Gossypium hirsutum L.) with tillage, cover crops, and nitrogen (N) rates. Soil samples (0‐ to 15‐cm depth) were analyzed for HSHT indicators (i.e., Solvita CO2–C, water‐extractable organic C [WEOC], water‐extractable organic N [WEON], and WEOC/WEON), two versions of soil health score (SHS) calculations (SHS2015 and SHS2018), and potential N mineralization (Nmin) rates. Additionally, H3A‐ and Mehlich‐1–based extractable soil nutrients were determined to test the fertility component of HSHT. The individual HSHT indicators, SHS2015, SHS2018, and Nmin showed inconsistent responses to management, where most variation in SHS was driven by WEON (0.68 < R2 > 0.86; p < .001). Additionally, H3A solution extracted nutrients with higher variability (18.5 <CV%> 76) than Mehlich‐1. This lack of consistent to response to management in southeastern U.S. croplands implies that comprehensive evaluation and/or modification of HSHT is required for broader applicability.

Soil erosion and corn yield in a cultivated catchment of the Chinese Mollisol region.

Evaluation of soil redistribution rates and influence on crop yield in agricultural catchments is very important information, which can provide a scientific basis for arrangement of soil and water conservation measures and sustainable crop production. In recent decades, the soil erosion has greatly aggravated in the Mollisol region of Northeast China due to unreasonable land management, which in turn has reduced crop yield. The objectives of this study were to investigate the spatial distribution of soil redistribution and the relationship between crop yield and soil redistribute at a catchment of the Chinese Mollisol region. A total of 176 soil samples were collected based on a 200 m by 200 m grid and 4 yr of corn (Zea mays L.) yields were measured. The 137Cs trace technique and Zhang Xinbao’s mass balance model indicated that the soil redistribution rates ranged from −7122.25 to 5471.70 t km−2 yr−1 and averaged −830.10 t km−2 yr−1. Soil erosion dominated in the research area. The corn yields for four years ranged from 43.24 to 136.19 kg km−2 and averaged 90.42 kg km−2. The spatial distribution of soil redistribution rates and corn yield showed a similar ribbon and plaque characteristics at the catchment. An equation between corn yield and soil redistribution rates was fitted and showed that there was a significant negative correlation between corn yield and soil erosion rates, while there was no relationship between the corn yield and soil deposition rates. Therefore, effective soil and water conservation measures are urgently needed to increase crop yield and realize sustainable land-use management.

Determining the Role of Plant‐Parasitic Nematodes in the Corn–Soybean Crop Rotation Yield Effect Using Nematicide Application: II. Soybean

Corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] crop rotation is well‐known to increase yields of both crops and is called the rotation effect. This study was conducted to determine the role of plant‐parasitic nematodes—particularly soybean cyst nematode (SCN, Heterodera glycines),—in the rotation effect for soybean. Research was conducted at a site in Waseca, MN, that was established in 1982 to study corn–soybean rotation. Included in the study were treatments in 1 to 5 yr of SCN‐susceptible soybean monoculture following 5 yr of corn, continuous SCN‐susceptible soybean monoculture, and continuous soybean with SCN‐resistant cultivars since 2010. Granular nematicides have been applied to half of each plot since 2010 to minimize nematode populations across crop sequences as a way to determine the role of nematodes in the rotation effect. Because nematicide was similarly effective in each crop sequence, it was not effective for determining if SCN damage varied by crop sequence. Soybean cyst nematode populations increased (P ≤ 0.05) in soybean monoculture and were negatively correlated with soybean yield (P ≤ 0.05). Pratylenchus (lesion nematode) populations decreased significantly in soybean monoculture particularly when comparing first and second year in soybean (P ≤ 0.05). Helicotylenchus (spiral nematode) and Xiphinema (dagger nematode) populations were significantly decreased in continuous soybean compared to most sequences in 5 or fewer years of monoculture (P ≤ 0.05). Trends in nematode populations suggest SCN may have had a role in the rotation effect for soybean yield, but that Pratylenchus, Helicotylenchus, and Xiphinema did not. Growing soybean in monoculture decreases yield. Growing soybean in monoculture increases soybean cyst nematode populations. There was some evidence that soybean cyst nematode can be involved in monoculture yield decline for soybean.

Investigating Spatial Distribution of Soil Quality Index and Its Impacts on Corn Yield in a Cultivated Catchment of the Chinese Mollisol Region

The Mollisol region of Northeast China is an important crop production base of China. The soil quality of this region has greatly decreased in recent decades due to unreasonable land management, which in turn has reduced crop yields. The objectives of this study were to investigate the spatial distribution of a soil quality index (SQI) and the relationship between crop yield and soil quality in a catchment of the Chinese Mollisol region. A total of 168 soil samples were collected based on a 200- by 200-m grid and 4 yr of corn (Zea mays L.) yields and 15 soil quality indicators, including physical, chemical, and biological properties, were analyzed. Principal component analysis indicated that the critical indicators for characterizing soil quality were soil organic matter, total N, sucrase activity, NH₄⁺–N, microbial biomass C, and microbial biomass N. The SQI varied from 0.147 to 0.804 with a mean value of 0.388. The spatial distribution of soil quality and corn yield showed that high values of both soil quality and corn yield were located in the north, and low values were in the south of the catchment. An empirical equation between corn yield and SQI was fitted, and cross-validation results showed that the empirical equations could be used to assess soil quality effects on corn yield with acceptable accuracy in the research area. Hence, to realize agricultural sustainability, effective soil conservation measures, such as no-till, cover crops, and retaining crop residues should be implemented in the study area instead of current cropland management measures.

Corn, Cotton, and Peanut Response to Tillage and Subsurface Drip Irrigation in North Carolina

Determining response of agronomic crops to subsurface drip irrigation (SDI) in conventional and reduced tillage systems is important in defining utility of SDI. Therefore, the objectives of this research were to define interactions of SDI and tillage with respect to yield and economic return of corn (Zea mays L.), cotton (Gossypium hirsutum L.), and peanut (Arachis hypogaea L.) planted in rotation. Research was conducted in two 4‐yr periods (2007–2010 and 2008–2011) in North Carolina using continuous strip tillage vs. continuous conventional tillage without irrigation or with SDI using a crop sequence of 1 yr of cotton, 2 yr of corn, followed by 1 yr of peanut. Corn, cotton, and peanut yields increased with SDI compared with no irrigation regardless of tillage system. Cotton and peanut yields were not affected by tillage system or the interaction of tillage and irrigation; corn yield was affected by this interaction. In the second year of corn, yield and economic return were higher in conventional tillage with SDI than strip tillage with SDI. Economic return for the sum of crops in the rotation was affected by the interaction of irrigation and tillage. Economic return was higher in both periods during each year corn was grown under SDI compared with non‐irrigated corn while higher economic returns for cotton and peanut under SDI were noted in one of two periods. When pooled over periods, crops, and tillage, economic return for SDI was US$1,552 ha−1 higher than non‐irrigated production over 4 yr.

Evaluating Soil Management Using Particulate and Chemically Labile Soil Organic Matter Fractions

Particulate organic matter (POM), an established soil quality indicator, is too costly for routine testing by analytical labs. Chemical oxidation of labile soil organic matter is less costly and may prove to be an equally effective indicator. The objectives of this study were to test the relationship between POM and chemically labile organic matter (CLOM) and to evaluate the effects of soil management on POM and CLOM. The study was conducted within a long‐term crop rotation × fertility treatment study in central Pennsylvania. Crop rotation sequences were continuous corn (Zea mays L.), corn–soybean [Glycine max (L.) Merr.], 4 yr of corn followed by 4 yr of alfalfa hay (Medicago sativa L.), and corn–oat (Avena sativa L.)–winter wheat (Triticum aestivum L.)–2 yr of red clover hay (Trifolium pratense L.). Fertilizer treatments were mineral fertilizer, N‐based liquid dairy manure, and P‐based liquid dairy manure. A significant linear relationship between POM‐C and CLOM‐C treatment means was observed (r2 = 0.74). Both POM‐C and CLOM‐C concentrations were greatest for manure‐based fertility treatments and for crop rotations receiving the most frequent applications of manure. Only CLOM‐C, however, distinguished between the N‐based and P‐based manure treatments. Further development of CLOM‐C as a soil quality indicator may yield a reliable, cost‐effective soil quality management tool.

Estimating Plant‐Available Water Across a Field with an Inverse Yield Model

The variability of crop yield in dryland production is primarily affected by the spatial distribution of plant‐available water even for seemingly uniform fields. The most productive midwestern soils, which are loess caps over glacial till or outwash, can have a wide range of water‐holding capacities in individual fields because of landscape processes and management. An inverse yield model was created as a robust method to quantify the spatial and temporal role of plant‐available water on large agricultural fields to improve management options in precision agriculture. Plant‐available water maps for a field were estimated from yield maps using inverse water‐budget modeling based on measurements of solar radiation, temperature, precipitation, and vapor pressure deficit. The model presented in this paper was applied to 5 yr of corn (Zea mays L.) yield‐monitor data from a field in Waunakee, WI, having three soil mapping units, Plano silt loam (fine‐silty, mixed, mesic Typic Argiudoll), St. Charles silt loam (fine‐silty, mixed, mesic Typic Hapludalf), and Griswold loam (Fine‐loamy, mixed, mesic Typic Argiudoll). The comparison of measured and inverse‐modeled plant‐available water suggests that the simple inverse yield model produces reasonable results in drier years with uncertainties of about 28 mm of plant‐available water. The model helped to quantify the role of plant‐available water in determining crop yield. Because of limited input requirements, the model shows promise as a practical tool for using precision farming to improve management decisions, and as a tool to obtain input for landscape‐based models.

Crop Sequence Effects on Soybean Cyst Nematode and Soybean and Corn Yields

The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a destructive pest of soybean, Glycine max (L.) Merr. Field research was conducted at Waseca and Lamberton, MN, from 1996 through 1999 to evaluate the effect of crop sequence on SCN population density and on crop yields. Cropping sequence treatments were (i) monocultures of corn (Zea mays L.), SCN‐resistant soybean, and SCN‐susceptible soybean; (ii) susceptible soybean rotated with 1, 2, or 3 yr of corn; (iii) resistant soybean rotated annually with corn; and (iv) rotation of corn–resistant soybean–corn–susceptible soybean. Egg density was determined at sowing and harvest, and crop yields were determined each year. In general, yields of resistant soybean were higher than susceptible soybean. Resistant soybean in annual rotation with corn produced the highest yield, and susceptible soybean in monoculture produced the lowest yield among all treatments. A longer period of corn in rotation resulted in higher yield of subsequent susceptible soybean in most instances. Yields of corn following corn were lower than following soybean. Egg density at the start of the study was 6994 and 14 000 eggs 100 cm−3 soil at Waseca and Lamberton, respectively. Average Pf/Pi (egg density at harvest/egg density at sowing) was 0.59 (0.23–0.86) for corn, 0.49 (0.21–0.73) for resistant soybean, and 3.3 (0.74–9.91) for susceptible soybean for all treatments at the two sites across the 4‐yr period. After 3 yr of corn, egg density decreased to 889 and 3695 eggs 100 cm−3 soil at Waseca and Lamberton, respectively. Annual rotation of resistant soybean and corn resulted in the lowest SCN population density and produced the highest yield of both crops.

Subsurface Drain Losses of Water and Nitrate following Conversion of Perennials to Row Crops

Nitrate losses through subsurface drains in agricultural fields pose a serious threat to surface water quality. Substantial reductions in drainage losses of NO3–N can occur with alfalfa (Medicago sativa L.) or perennial grasses as used in Conservation Reserve Program (CRP) plantings. Conversion of perennials to annual row crops, however, could have rapid, adverse affects on water quality. We evaluated water and N use efficiency of row crops following perennials, and losses of water and NO3–N to subsurface drains. Four cropping systems: continuous corn (Zea mays L.), a corn–soybean [Glycine max (L.) Merr.] rotation, alfalfa (ALF), and CRP, were established in 1988. The ALF and CRP were converted to a corn–corn–soybean sequence from 1994 through 1996 while continuous corn (C‐C) and corn–soybean (C‐S) rotations were maintained. Following CRP, corn yield was 14% and water use efficiency (WUE) 20% greater as compared with C‐C. Yield was 19% and WUE 21% greater for soybean following corn in CRP and ALF as compared with C‐S. Residual soil NO3–N (RSN) increased 125% in first year corn following CRP and was 32% greater than C‐C by 1996. High N uptake efficiencies of corn following alfalfa slowed the buildup of RSN, but levels were equal to row crop systems after 2 yr. Nitrate losses in drainage water remained low during the initial year of conversion, but were similar to row crop systems during the subsequent 2 yr. Beneficial effects of perennials on subsurface drainage characteristics were largely negated following 1 to 2 yr of corn.

Weed Seed Bank Dynamics During a Five-Year Crop Rotation1

Cultural practices used for crop production influence the composition of the weed seed bank in the soil. This paper reports the results of a 5-yr experiment to characterize the weed seed bank conducted on a farmer-managed field in central Iowa. The number of weed seeds in the soil and their vertical distribution were examined each October. At the initial sampling in October 1994, the field had been in hay production and about 80% of the weed seeds were common waterhemp and foxtail species. The cropping sequence over the next 3 yr was corn/soybean/corn using a ridge tillage system. Over this period, the density of common waterhemp seeds declined each year. The density of foxtail seeds declined by almost 90% during the first year of corn and did not change during the following years of soybean and corn production. Prior to moldboard plowing of the hay sward in 1994, weed seeds were concentrated in the upper 10 cm of soil. Moldboard plowing resulted in a more uniform distribution of the weed seeds over the upper 20 cm of soil, and the distribution across depths remained relatively constant during the 3 yr of corn and soybean production. During the final year of the experiment, the field was rotated to oat and reseeded with hay species. The number of common waterhemp and foxtail seeds in the soil greatly increased following oat/hay production and seeds were concentrated in the upper 10 cm of the soil profile. Results indicated that the processes affecting the weed seed bank in production fields are complex and will vary greatly based on the production practices used and the timing of their application.Nomenclature: Common waterhemp, Amaranthus rudis Sauer #3 AMATA; corn, Zea mays L.; foxtail species, Setaria spp.; oat, Avena sativa L.; soybean, Glycine max (L.) Merr.Additional index words: Cropping systems, ridge tillage, seed bank, seed distribution.

Cropping Intensity and Nitrogen Management Impact of Dryland No-Till Rotations in the Semi-Arid Western Great Plains

Crop N needs are not usually predicted based on cropping intensity or on tillage practice. However, N fertilizer requirements may increase dramatically as less fallow and less tillage are used in semi-arid regions of the Great Plains where summer fallow cropping is common. This long-term experiment was conducted to study the influence of N fertilizer rate, source/placement/timing (NSP), and crop rotation factors on the production of winter wheat (Triticum aestivum L.), corn (Zea mays L.), and grain sorghum (Sorghum bicolor L.), as well as their fertilizer N use efficiency (FNUE) for the initial years of conversion to no-till dryland farming. Research was conducted from 1987 through 1992 on two soils (Keith clay loam, a fine-silty, mixed, mesic Aridic Argiustoll and Weld loam, a fine-silty, mixed, mesic, Aridic Argiustoll) in eastern Colorado. Rotations included winter wheat-fallow (WF) and winter wheat-corn or grain sorghum-fallow (WCF). Wheat yields were similar between WF and WCF with adequate N application. Response to N fertilizer at lower rates was greater in WCF than WF because of its greater depletion of soil N. Corn production averaged 72 bu/acre with adequate N and required 1 Ib/acre of N uptake to produce 1 bu/acre of grain. Current N fertilizer recommendations for wheat and corn were not adequate to insure maximum production under no-till management. Fertilizer placement significantly affected average annual rotational yield (40 to 70 Ib/acre per yr difference) but application rate was more important economically. Grain biomass produced in each rotation per pound of total plant N uptake (GNUE) was 17 Ib/acre per yr in WF compared with 29 Ib/acre per yr for WCF. This 70% increase in average annual grain production of WCF over WF was accomplished with a 44% annual increase in fertilizer N application.

Impact of Crop Rotation and Tillage System onHeterodera glycinesPopulation Density and Soybean Yield

The long-term effects of no-till planting practices and rotation on the population dynamics of the soybean cyst nematode (Heterodera glycines) and soybean yield were investigated in field experiments over a period of 8 yr. The experiment was a 2 X 4 factorial, comparing no-till vs. conventional tillage practices in four cropping patterns (continuous soybean, a 1-yr rotation of corn and soybean, a rotation of 2 yr of corn followed by soybean, and a corn-wheat/soybean double-cropping system). Treatments were arranged so that each combination occurred every year after 1986. Soybean after 1 yr of corn had higher yields (P = 0.0001) than soybean after soybean. Two years of corn between soybean crops resulted in soybean yields higher than those after 1 yr of corn in only 2 out of 6 yr. The yields of soybean in the corn, wheat/soybean double-cropping system, however, were generally similar to monoculture soybean. No-till practices had positive or no effects on soybean yield early in the study, but yields of no-till soybean were lower (P = 0.01) than conventionally tilled soybean after several years because weed pressure was greater in no-till plots. Population densities of H. glycines were greater (P < 0.10) in conventionally tilled plots than in no-till plots in 1988 and 1990-1992. Numbers of H. glycines fluctuated in an unpredictable manner from year to year, possibly because of unidentified biological control agents or excessive moisture in certain years. H. glycines population densities declined in a predictable manner when a nonhost was planted

Tillage, Rotation Sequence, and Cultivar Influences on Brown Stem Rot and Soybean Yield

Yield of soybean [Clycine max (L.) Merr.] is often reduced when grown in fields using no-till (NT) and shorter crop rotations with corn (Zea mays L.) than with conventional tillage (CT) and longer crop rotations. The objective of this study was to determine the effect of tillage system, rotation sequence, and cultivar on severity of brown stem rot (BSR) [caused by Phialophora gregata (Allington and D.W. Chamberlain) W. Gams] and yield of soybean. Field studies were conducted near Arlington, WI, for 4 yr (1989-1992) on a Plano silt loam (fine-silty, mixed, mesic Typic Argiudoll) under both NT and CT [...]

Modeling Alternatives to Reduce Dairy Farm and Watershed Nonpoint Source Pollution

AbstractManagement practices are available that may reduce sediment or phosphorus (P) loading to streams draining agricultural land. An evaluation of the long term effects of implementing one or more of these practices is needed. We used the Erosion Productivity Impact Calculator (EPIC) and Agricultural Non‐Point Source (AGNPS) models to evaluate 20 management practices for sediment and P yields from 4 ha fields in a 1272 ha watershed of dairy farms. Five crop sequences [continuous corn (Zea mays L.) CC(OA)AAA, CC(OA)AAAA, CCC(OA)AAA, and CCCAAA; 0, oat (Avena sativa L.); A, alfalfa (medicago sativa L.)] combined with either fall moldboard plowing (mFMP), chisel plow (mFCP), no‐till (mNT), or no‐till substituting anhydrous ammonia for manure (aNT), were imposed on a toposequence of three Alfisols. The normal sequence, 2 yr of corn, oat/alfalfa seeding, 3 yr of alfalfa with fall application of solid manure followed by moldboard plowing, CC(OA)AAA‐mFMP, served as reference. Scenarios were subjected to 42 yr of simulated local climate. Scenarios with 43% or less row crop and mNT on a 4% sloping soil reduced sediment yield from 24 to 47%, at edge of field, but increased total P yield from 158 to 338%, mostly as soluble P. The EPIC output parameters (soil loss ratio [C] for June, erodibility [K], Manning's n, and SCS curve number [CN]) served as inputs to the (AGNPS) model, a cell based single rainfall event model that simulates runoff, sediment, and P yields from a watershed. Crop sequences not exceeding 43% corn and mFCP or aNT reduced watershed sediment yield 13 to 41%, but increased total P yield by 44 to 113% as compared with CC(OA)AAA‐mFMP. Average annual costs were $11 ha−1 less for these sequences when compared with CC(OA)AAA‐mFMP.

Comparative plowdown value of red clover strains

Cultivars and common seedlots of double- and single-cut red clover (Trifolium pratense L.) were direct seeded at the Elora Research Station in 1982 and 1983, fall plowed, and followed by 3 yr of corn (Zea mays L.) harvested for grain yield. The 1982 and 1983 sites differed in background soil N status. Common seedlots produced subsequent corn yields equal to those following certified cultivars, indicating no advantage to the use of certified seed for plowdown purposes. Although double-cut strains produced more aboveground biomass, both in midseason and at plowdown, single-cut strains produced more fall root biomass (1 yr only) and a higher percent root N, but in the end, corn yield did not differ between double- and single-cut strains. The ranges of performance of double- and single-cut strains did not overlap for aboveground biomass, but overlapped substantially for both root and percent shoot N and for root biomass. First-year corn yield varied significantly with red clover strain, in both the double- and single-cut groups, although no strain differences were apparent by the second and third years. Compared to continuous corn with no N fertilizer, red clover increased corn yield by 1.5–1.8 t ha−1 in Year 1, by 0.4–0.9 t ha−1 in Year 2, and by 0–0.7 t ha−1 in Year 3. First-year corn yield was not significantly correlated with red clover parameters measured the preceding year, including aboveground biomass and nitrogen content at plowdown. However, observed patterns of response were consistent with a nitrogen-based plowdown benefit. Breeding to improve plowdown value will depend on identification of those specific plant attributes which confer legume plowdown benefit.Key words: Plowdown, green manure, red clover, nitrogen, corn

Crop Rotation and Tillage Effects on Corn Growth and Soil Structural Stability

AbstractIncreasing concerns about soil degradation with continuous corn (Zea mays L.) production and a scarcity of scientific information regarding corn grown in rotation with the diversity of crops produced in Ontario, prompted a long term study on the effect of various crop rotations and their interaction with two tillage systems on corn growth and soil structure. Eight rotations were established in 1980 which included continuous corn, six rotations comprised of 2 yr of corn following 2 yr of another crop or crop sequence, and continuous alfalfa (Medicago sativa L.). Each rotation was divided into either conventional tillage (fall moldboard plow) or minimum tillage (fall chisel plow). First‐year corn grown in rotation yielded 3.9% more than continuous corn for conventional tillage and 7.9% more than continuous corn for minimum tillage. These corn responses to rotation were smaller than most of those reported in the literature. When barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) were the preceding crops, interseeding red clover (Trifolium pratense L.) increased first year corn yields only on conventionally tilled plots. Corn plant development was consistently slower with minimum tillage compared to conventional tillage. Yields were significantly lower with minimum tillage for continuous corn and where corn followed wheat interseeded with red clover. Little or no response to rotation was observed in second‐year corn. The seedbed with continuous corn had a lower proportion of fine aggregates compared to corn grown in rotation. In most years soil aggregate stability was highest under continuous alfalfa and including a legume (whether alfalfa or interseeded red clover) in the rotation improved aggregate stability compared to continuous corn.

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.