Crop, Forage and Turfgrass Management最新文献

Switchgrass (Panicum virgatum L.) is an important warm-season perennial grass in livestock systems and has been evaluated as an herbaceous energy crop. Switchgrass growth varies across environments. To accurately predict morphology, locally developed morphological development equations are needed. The objectives of this study were to compare the morphological development of a recently developed biofuel cultivar ‘Liberty’ to an improved forage cultivar ‘Shawnee’ in multiple environments in Indiana and to predict morphological development in response to growing degree days (GDD) and day of year (DOY). Pure stands of each cultivar were sampled weekly and biweekly at multiple locations in Indiana in 2016 and 2017. Morphological development was determined by the mean stage count (MSC) and mean stage weight (MSW) system. Prediction equations based on GDD and DOY for both MSC and MSW were developed from northern and central Indiana locations and validated using data from an independent site in west central Indiana. MSC and MSW were linearly related to GDD and had a quadratic relation to DOY. Significant main effects for GDD-based prediction included location and cultivar (P < .01), while DOY-based predictions included location (P < .01). Prediction r² on the independent validation dataset ranged from 96% to 98% for both MSC and MSW. When predicting MSW at the validation location, the GDD and DOY equations had r² values from 97% to 98%. Morphology predictions based on GDD and DOY resulted in similar r² values, suggesting that either measure could be used to accurately predict growth in Indiana.

Annual forages are commonly planted in open pasture in the Mid-South, but there is little information on the productivity of these forages when incorporated into silvopasture. The objective was to evaluate four annual forages adapted to the Mid-South, namely, arrowleaf clover (Trifolium vesiculosum Savi), crimson clover (Trifolium incarnatum L.), tetraploid annual ryegrass (Lolium multiflorum L.), and diploid annual ryegrass (Lolium multiflorum L.), in a loblolly pine (Pinus taeda L.) silvopasture for seasonal forage mass distribution and annual forage accumulation. The forages were tested in a randomized complete block design with three replicates and three harvests per year: Harvest 1 (H1, April), Harvest 2 (H2, May), and Harvest 3 (H3, July) from 2020 to 2022. Both annual ryegrass types had greater forage mass for H1 and H2, with minimal regrowth after H2 and low forage mass for H3. Both annual ryegrass types outperformed the legumes, which largely failed to establish in this environment, contributing <22% of forage mass across harvests despite adequate soil pH, seed bed preparation, and inoculation. Both annual ryegrass types had greater forage mass in the loblolly silvopasture system for H1 and H2 and are more suitable forages for the system than the legumes tested.

Many golf course superintendents rely on plant growth regulators (PGRs) as a primary means of managing Poa annua L. in creeping bentgrass (Agrostis stolonifera L.), particularly the early-stage gibberellic acid inhibitor paclobutrazol (Trimmit 2SC; Syngenta Professional Products). While herbicides for Poa annua control are often applied during fall and winter, there is limited information regarding the efficacy of shoulder season PGR applications for Poa annua control. Trials were conducted in Knoxville, TN, during 2023 and 2024, to evaluate the efficacy of prohexadione-calcium (Anuew EZ; Cleary Chemicals) at 18 fl oz ac⁻¹, prohexadione-calcium + paclobutrazol at 18 fl oz ac⁻¹ + 5 fl oz ac⁻¹, trinexapac-ethyl (Primo Maxx; Syngenta Professional Products) at 6 fl oz ac⁻¹, trinexapac-ethyl + paclobutrazol at 6 fl oz ac⁻¹ + 5 fl oz ac⁻¹, and paclobutrazol at 5 fl oz ac⁻¹. A non-treated check was included for comparison along with the selective herbicide methiozolin (PoaCure; Moghu USA) at 0.2 gal ac⁻¹. PGR treatments were applied at ∼14-day intervals during October and November and at ∼28-day intervals thereafter. Methiozolin was applied twice in the fall of each year. Prohexadione-calcium + paclobutrazol, trinexapac-ethyl + paclobutrazol, and paclobutrazol alone controlled Poa annua 75%–88% by 22 weeks after initial treatment (WAIT) in 2023 and 93%–94% by 22 WAIT in 2024. Combinations of prohexadione-calcium or trinexapac-ethyl with paclobutrazol led to a reduction in Poa annua coverage of ≥80% compared with non-treated check plots at 22 WAIT in 2024. Transient creeping bentgrass injury was observed yearly with paclobutrazol-containing treatments and was likely related to overregulation from applying treatments when ≤196 growing degree days had accumulated.

Limited herbicide options are available for selective weed management in roadside native plantings. Thus, this field study evaluated blackeyed Susan's (Rudbeckia hirta L.) tolerance to four postemergence (POST) herbicides—quinclorac, florpyrauxifen-benzyl, clopyralid, and metsulfuron—during prairie establishment in Fayetteville, AR, across two growing seasons in 2022 and 2023. Blackeyed Susan was assessed for plant incidence, bloom count, and visible injury. In 2022, no reduction in blackeyed Susan blooms was detected in response to POST herbicides; however, peak bloom counts occurred 1 week after treatment (WAT) and ranged from 1.1 to 1.6 blooms per ft². In 2023, at 10 WAT, blackeyed Susan plants were detected in 56% of nontreated plots, and selected POST herbicides greatly reduced blackeyed Susan plant densities: clopyralid (7%), florpyrauxifen-benzyl (20%), metsulfuron (31%), quinclorac (39%). Similarly, blackeyed Susan exhibited unacceptable injury in response to POST herbicides, with each treatment causing ≥80% injury at 4 WAT in 2023. Reductions in plant stand and bloom count, in addition to the severe injury seen in blackeyed Susan, indicate that the selected POST herbicides are not a viable weed management option during the establishment of blackeyed Susan plantings.

Optimal soybean [Glycine max (L.) Merr.] production requires accurate, stage-specific management practices to mitigate abiotic and biotic stressors. From emergence to full maturity, a soybean plant's physiological needs and vulnerabilities change as it transitions through its vegetative and reproductive cycles. This management guide details each growth stage, provides clear descriptions, and identifies the common risks encountered. For different growth stages, strategic management recommendations are presented, emphasizing proactive approaches to mitigate potential yield limitations. The objectives of this management guide are (a) to clearly define the distinct growth stages of the soybean plant and (b) to discuss common risks and provide research-based management recommendations applicable at each stage.

Spring weed control in established alfalfa (Medicago sativa L.) has historically relied heavily on paraquat. However, new regulatory safety measures introduced to ensure the safe use of paraquat may deter growers from relying on paraquat. Field studies were conducted in Idaho and Utah in 2023 and 2024 to assess weed control, alfalfa recovery, forage accumulation, and nutritive value following treatment with carfentrazone, saflufenacil, pyraflufen, tiafenacil, diuron + hexazinone, glyphosate, and paraquat. The main goal was to assess whether carfentrazone, saflufenacil, pyraflufen, tiafenacil, and diuron + hexazinone could be viable alternative herbicides to paraquat that growers can use for weed control in the spring in established alfalfa. Although carfentrazone, saflufenacil, and tiafenacil caused greater alfalfa injury and height reduction within the first 3 weeks after herbicide application, the alfalfa recovered within 6 weeks after herbicide application. At the Idaho site, all the evaluated herbicides provided similar or better weed control than paraquat, and there was no difference in alfalfa hay forage accumulation or nutritive value among the herbicide treatments, especially when compared with paraquat treatment. At the Utah site, saflufenacil and diuron + hexazinone reduced alfalfa hay forage accumulation when compared with the paraquat treatment, suggesting that farmers would have to wait longer to allow alfalfa to recover after applying saflufenacil or diuron + hexazinone. Overall, these results show that carfentrazone, pyraflufen, saflufenacil, and tiafenacil are promising alternatives to paraquat for weed burndown in alfalfa.

Recent technological advancements have led to the release of several commercially available near-infrared (NIR) solutions, especially with handheld portable spectrometers. We define a NIR solution as the integration of hardware, software, and standardized operating protocols for handling and scanning samples. Rather than relying solely on pre-loaded calibrations, which may not always meet accuracy requirements or be available for a specific application, NIR users can benefit from being able to develop custom calibrations. We hypothesized that, despite inherent differences in spectra and scanning protocols, custom calibrations developed using a single software pipeline could yield comparable performance across different NIR solutions. Spectra from 317 dried–ground forage samples (grass–legume mixtures) were collected using two portable handheld spectrometers (Trinamix and NeoSpectra) and used to develop NIR models to predict forage nutritive value (crude protein and in vitro organic matter digestibility). During the scanning process, the samples were in direct contact with the Trinamix spectrometer, whereas for the NeoSpectra spectrometer, scanning was performed through a sampling container. Despite differences in the spectra, NIR-predicted values closely aligned with the laboratory reference values, showing a strong model fit for both NIR solutions. All models achieved r² values ≥0.90, with bias ranging from –0.22% to –0.17% and SE of prediction (SEP) ranging from 1.8% to 2.3%. Different model parameterization was needed to optimize the performance of each NIR solution. Our findings demonstrate that flexible software can support the development of custom NIR models, paving the way for tailored, user-defined NIR solutions.

The primary aim of this study was to investigate the impact of lactic acid bacteria (LAB) strains on the quality of whole-plant corn (Zea mays L.) silage. Three LAB strains were selected from previous studies: Lactiplantibacillus plantarum (LP), Levilactobacillus brevis (LB), and Lentilactobacillus buchneri ssp. silagei (LS), along with their mixture (MX). Whole-plant corn was harvested, cut into 1- to 2-cm pieces, and ensiled either directly (control [CTRL]) or after treatment with LAB inoculants. LAB were applied at a final dose of 1 × 10⁶ colony-forming units g⁻¹. Vacuum pouches were fermented for 3, 7, and 90 days, and the quality, microbial populations, and aerobic stability of the silage were measured. The interaction between inoculation and storage time significantly affected dry matter (DM), ether extract (EE), pH, ammonia nitrogen (NH₃-N), lactic acid (LA), acetic acid, and propionic acid concentrations. MX reduced the DM loss and lowered neutral detergent fiber and acid detergent fiber at 90 days but had no effect on crude protein and EE content. At 90 days, inoculation with MX decreased pH (0.21) and NH₃-N (1.27) of silage with respect to CTRL (P < .05). Both MX and LB increased the content of water-soluble carbohydrates and LA (P < .05). Inoculation improved aerobic stability and increased the count of LAB (P < .05) while reducing the count of yeast, aerobic bacteria, and mold. Comprehensive evaluation revealed that inoculation with MX had the most favorable effect on the nutritional and fermentation quality of corn silage, reducing the growth of harmful microorganisms and delaying aerobic spoilage.

A significant loss of seed quality may occur for planting under traditional on-farm chickpea (Cicer arietinum L.) seed storage techniques. We evaluated six alternative seed storage techniques over a 6-month period: (a) polypropylene bags (PPBs; traditionally used for on-farm seed storage), as the control; (b) filter cake (FC)–blended seed stored in PPBs (PPB+FC); (c) plastic drums (PDs); (d) FC-blended seed stored in PDs (PD+FC); (e) Super Grain Pro bags; and (f) Purdue Improved Crop Storage bags. The evaluation was conducted under ambient laboratory conditions at the Ethiopian Biodiversity Institute and the Bishoftu Agricultural Research Center. Storage conditions, seed moisture content (SMC), seed germination (SG), seedling length, seedling dry weight, and seed vigor index I were measured every 2 months for 6 months. The results showed that the SMC of seed stored using alternative methods varied from 9.3% to 11.3%, whereas those in PPB had SMC ranging from 12.3% to 12.7% after 6 months of storage at the two locations. High SG was maintained by alternative storage techniques, ranging from 90.0% to 92.7% over 6 months at both locations. However, seed stored in the PPB for 6 months at the BARC had the lowest SG (78.7%). Hermetic bags maintained chickpea seed vigor throughout the storage period at both locations. In contrast, the non-hermetic storage technique resulted in a significant decline in seedling vigor over 6 months at both locations. This study found that hermetic seed storage technologies can preserve seed quality for 6 months, regardless of the storage location. Therefore, this study affirmed the need to promote effective alternative seed storage technologies to enhance chickpea productivity and farmers’ livelihoods.

Soybean [Glycine max (L.) Merr.] variety selection is a crucial decision that impacts farm profitability. Effective variety selection requires performance evaluation across diverse environments to determine whether differences are due to genetic or nongenetic factors. Producers should use different types of multiple-location variety trials to select high-yielding varieties with resistance or tolerance to biotic and abiotic stressors prevalent in their region. In addition, information on other traits (e.g., plant height, lodging, green stem) that can be obtained should be considered when selecting a variety. Two different types of variety trials that are normally conducted by university extension programs and seed companies consist of replicated small-plot trials and on-farm large strip-plot demonstrations. The data from these trials are normally published in printed publications, downloadable online data sheets (e.g., PDFs, spreadsheets), and user-friendly online selection tools. The objectives of this management guide are to (a) describe replicated small-plot trials and unreplicated on-farm large strip-plot demonstrations, including attributes of each type; (b) demonstrate a data-driven approach to selecting high-yielding varieties with resistance to biotic and abiotic stressors; and (c) discuss additional agronomic and seed quality traits that aid in understanding the differences in varieties. Data and interpretation from multiple-location official variety trials and on-farm strip-plot demonstrations from the Louisiana State University Agricultural Center were used to demonstrate results commonly available from university extension programs. Evaluating yield and stress resistance data across multiple locations and years, including both replicated small-plot trials and on-farm strip-plot demonstrations, provides the most reliable basis for selecting varieties adapted to diverse and unpredictable environmental conditions.