Crop, Forage and Turfgrass Management最新文献

The occurrence of S deficiency in Midwest crops in the past 20 years is likely a result of the consistent decline of atmospheric S deposition during this time period. In the absence of intentional S fertilization, crops utilize SO₄-S mineralized from soil organic matter and potentially the incidental application of S in non-S fertilizers. Based on the analysis of hundreds of P fertilizer samples in 2021 and 2022, we found monoammonium phosphate (MAP), diammonium phosphate (DAP), triple superphosphate (TSP), and ammonium polyphosphate (APP) had SO₄-S concentrations of 1.88 ± 0.35, 1.80 ± 0.30, 1.66 ± 0.27, and 0.61 ± 0.18% SO₄-S (mean ± standard deviation), respectively. If MAP, DAP, and TSP are applied to replace P removal of average yielding corn (Zea mays L.) and soybean (Glycine max L.) crops grown in rotation, SO₄-S applied by MAP, DAP, and TSP at median and 3rd quartile values would be 4.0–4.6 lb SO₄-S acre⁻¹, approximately equivalent to ∼42–52% of the S removed in the grain of a single crop. If used as a starter fertilizer (5 gal acre⁻¹) APP would apply <0.4 lb acre⁻¹, <4% of grain S removal. The crop availability of SO₄-S in P fertilizers is conditional on the timing of their application relative to crop need, soil properties, and rainfall in addition to the amount of S applied. The contribution of P fertilizers to S cycling in environmental studies should also be considered.

Tumble windmill grass (Chloris verticillata Nutt.) is a problematic perennial grass weed in the semiarid Central Great Plains (CGP). Greenhouse and fallow field experiments were conducted during 2021 and 2022 at Kansas State University Agricultural Research Center near Hays, KS, to determine the effectiveness of various POST herbicides for tumble windmill grass control. All selected POST herbicides were applied at field-recommended rates at the seedling growth stage (3-to 4-inches tall) of tumble windmill grass in greenhouse study. Tumble windmill grass was at the heading growth stage (10-to-12-inches tall) in fallow fields when POST herbicides were tested. Results from greenhouse study indicated that quizalofop-P-ethyl (QPE) and clethodim provided ≥ 95% control and shoot biomass reduction of tumble windmill grass at 28 days after treatment. Glyphosate provided 89% control and 93% shoot biomass reduction of tumble windmill grass. Imazamox and nicosulfuron had the least control (41 to 51%) and shoot biomass reduction (43 to 66%) of tumble windmill grass in greenhouse study. In contrast, all tested POST herbicides were comparatively less effective on tumble windmill grass (≤68% control and ≤ 50% shoot biomass reduction) except glyphosate (85% control and 54% shoot biomass reduction) in field study. These results conclude that clethodim, QPE, and glyphosate applied at early growth stages can provide effective control of tumble windmill grass in the CGP region.

In the mid-southern United States, rice (Oryza sativa L.) is flooded primarily to suppress weed germination and growth. Two experiments were conducted to determine whether herbicide performance in conventional or Clearfield rice weed control programs was affected by intermittent flooding. The effects of flooding and herbicide program on barnyardgrass [Echinochloa crus-galli (L.) P. Beauv] control, rice grain yield, and water applied were investigated at the Delta Research and Extension Center in Stoneville, MS, on Sharkey clay (very fine, smectitic, thermic Chromic Epiaquert). For herbicides commonly applied in conventional (clomazone, quinclorac, pendimethalin, thiobencarb, fenoxaprop-ethyl, cyhalofop-butyl, and bisypriboac sodium) or Clearfield rice weed control programs (imazethapyr plus bispyribac-sodium followed by imazethapyr, imazamox or bispyribac-sodium), intermittent flooding had no adverse effect on barnyardgrass control relative to a continuous flood. Moreover, initiating irrigation when the perched water table drops to 8 inches below the soil surface had no effect on rice grain yield and reduced water applied by 51%. Mid-southern US rice producers can capture the water-saving benefits of intermittent flooding while having no adverse effects on herbicide activity or crop productivity in conventional and Clearfield systems.

Biochar soil amendment, a product of anoxic thermochemical conversion of biomass through a pyrolysis process, may help mitigate greenhouse gas (GHG) emissions from agricultural soils (Huang et al., 2023; Verheijen et al., 2010). Biochar application to field soils include improvements in pH of acidic soils, cation exchange capacity, and water holding capacity (Agegnehu et al., 2017; Alkharabsheh et al., 2021; Tokas et al., 2021; Ye et al., 2020).

Crop yield response to biochar application is variable but has been generally found as neutral or positive, with largest yield responses in acidic soils likely due to a liming effect of the biochar (Huang et al., 2023). Although crop yield response to biochar application has been globally studied, there have been limited field studies conducted

under field conditions in the Midwestern United States. In growing environments similar to Ohio and Michigan, a meta-analysis and modeling approaches found crop yield response to biochar to be small (< 10% across crops and −2.6 to 0.6% for corn (Zea mays L.) (Aller et al., 2018; Huang et al., 2023).

Although there have been previous studies on biochar's effect on corn and soybean [Glycine max (L.) Merr.] yield, farmers in Ohio and Michigan need to understand the potential yield outcomes of biochar application using production practices and crop rotations representative of the region. The objective of this research was to evaluate biochar application on corn and soybean yield.

A field experiment was established at three locations in Fall 2020 with biochar application and continued in 2021 with corn planting and 2022 with soybean planting. Locations included The Ohio State University (OSU) Western Agricultural Research Station (WARS) near South Charleston, OH (39°51′41.40″ N, 83°40′30.36″ W), OSU Northwest Agricultural Research Station (NWARS) near Custar, OH (41°13′6.6″ N, 83°45′48.24″ W), and Michigan State University (MSU) Agronomy Farm in East Lansing, MI (42°42′52.41″ N, 84°27′42.40″ W). The soil series are Kokomo (fine, mixed, superactive, mesic Typic Argiaquolls), Hoytville (fine, illitic, mesic Mollic Epiaqualfs), and Riddles (fine-loamy, mixed, active, mesic Typic Hapludalfs)–Hillsdale (coarse-loamy, mixed, active, mesic Typic Hapludalfs) complex at WARS, NWARS, and MSU, respectively. Prior to experiment initiation, 20 soil samples were collected from the entire field area, homogenized, and tested for soil properties (Table 1). Based on state guidelines, P, K, Ca, and Mg levels were sufficient (Culman et al., 2020).

The experiment was a randomized complete block design with two treatments (biochar and non-treated control) and four replications. At MSU, plots were 40 ft long by 20 ft wide, and the field was fallow in 2020 due to COVID-19 restrictions. At NWARS and WARS, each plot wa

Rye (Secale cereale L.) grain production in Kentucky is insufficient to meet the needs of distillers and bakers, in part because there is a knowledge gap about rye management that discourages farmers from choosing this crop. We conducted an economic study to develop recommendations for profitable rye grain production. The aim of this study was to determine the influence of two different nitrogen (N) rates (35 lb N acre⁻¹ and 70 lb N acre⁻¹) on yield and profitability of winter rye grain production. Experiments were conducted in 2020–2021 season at three Kentucky locations: Lexington, Princeton, and Adairville. Twenty-four rye entries were planted in a split plot design experiment and the two N rates (35 lb N acre⁻¹ and 70 lb N acre⁻¹) were assigned to main plots. There was no significant difference in mean yield between 35 and 70 lb N acre⁻¹. This indicates that less investment in N fertilizer will not adversely affect grain yield level, will enhance profitability of production, and will benefit distillers due to the higher alcohol yield associated with higher starch and lower protein levels.

The inter-annual corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation field is a well-known management practice that increases the yield of both crops across the midwestern United States. Each spring, farmers must decide which crop will be planted first. Prioritizing the planting of one crop can delay planting of the other, which can result in substantial yield loss and reduced associated revenue. The objective of this work was to assess how gross farm revenue (corn + soybean acres) can be affected by crop planting order (corn first, soybean second, and vice versa). The impact of variable planting dates on the yield of each crop was simulated for 310 fields across the United States. Gross farm revenue was estimated as a function of crop planting date, order, input costs and crop prices. In a randomly chosen field in south central Wisconsin, 1 out of the 310, delaying planting after May 1 reduced yield of each crop and subsequently suppressed gross farm revenue. Crop planting order determined farm revenue due to a variable loss in per day yield rate within the nominal planting timeframe associated with the two crops. In addition, the degree to which management intensified for each crop relative to crop yield potential accruing with earlier planting varied by state and further impacted farm revenue. Overall results suggest that to determine planting order, US farmers need to be aware of the comparative yield trends associated with delayed planting of corn vs. soybean for their specific farms and cropping systems and should also account for projected crop selling prices.

Accurate quantification of damage associated with root lodging events can help producers assess damage, predict potential yield losses, and help understand potential issues with grain quality that may arise post-harvest (i.e., kernel weight reductions, premature germination on the ear, or vivipary). The objective of this research was to utilize imagery from an uncrewed aerial vehicle (UAV) to accurately quantify crop canopy height, grain yield, and identify trends in imagery data associated with grain quality after root lodging was imposed at multiple growth stages. Simulated corn (Zea mays L.) root lodging experiments were conducted in 2018 and 2019 with lodging treatments applied at two vegetative or two reproductive growth stages (V10, V14, VT/R1, and R3). At dough stage (R4), visible-color and multispectral images were collected from each trial. Bare fields were also flown in February to obtain baseline elevation data. Imagery data were used to develop digital surface model (DSM) images and used to calculate indices of normalized difference red edge (NDRE) and normalized difference vegetation index (NDVI). Individual datapoints within each experimental plot were extracted from the imagery files and were compared to ground-truth measurements. The DSM height values were similar to actual measured heights for most lodging treatments (Adj. R² = .957). Both NDRE and NDVI exhibited linear trends with height and quality parameters (Adj. R² = .25–.54), though yield patterns were best described using a quadratic model (Adj. R² = .42–.60). These procedures hold utility in accurately quantifying canopy height following a root lodging event and hold promise in helping consultants identify yield and grain quality reductions associated with root lodging.

Planting date and seeding rate are two of the most basic and important factors in determining yield potential in winter wheat (Triticum aestivum L.) due to their impact on stand establishment. Timely planting of winter wheat (within a few days after the Hessian fly free date) ensures sufficient time for fall growth and tillering, which are critical for maximizing yield, while adequate seeding rate is necessary to optimize the number of heads per unit area. Field experiments were conducted in Mason, MI during three growing seasons (2020–2022) utilizing five planting dates, ranging from mid-September to mid-November, and five seeding rates ranging from 0.8 to 2.4 million seeds acre⁻¹. There was no interaction between planting date and seeding rate in determining yield. Yields declined by 22–48% from the earliest to the latest planting dates in response to a 33–47% reduction in the number of heads acre⁻¹. Seeding rate did not significantly impact yield except at low seeding rates under delayed planting. Maximum yield was achieved with a seeding rate of 0.93, 1.37, 1.47, 1.54, and 1.85 million seeds acre⁻¹ during the mid-September, late September, mid-October, late October, and mid-November plantings, respectively. Overall, results demonstrated that timely planting of wheat is critical for maximizing yield, with significant yield reductions occurring when planting is delayed, regardless of the seeding rate used. Furthermore, while low seeding rates may be used within the optimal planting window without yield penalty, seeding rates should be progressively increased as planting is delayed to diminish yield loss.