Crop, Forage and Turfgrass Management最新文献

Mild winter temperatures in the southeastern United States allow for the implementation of cool-season annual forage on dormant warm-season perennial pastures of bahiagrass (Paspalum notatum Flüggé). However, establishing cool-season forages in low-input systems requires overcoming the challenges of limited precipitation and inadequate plant nutrition. No-till (NT) and split N fertilizer management strategies may mitigate these challenges by preserving soil moisture and matching N needs to plant uptake. A 2-year study in north-central Florida evaluated the effects of increasingly intensified tillage practices, from conventional tillage (CT) to NT, with or without chemically dormant sod, using single versus split N fertilizer management approaches on the productivity of cool-season annual grasses with and without the presence of legumes. Nitrogen was either applied once right after planting (80-0 lb ac⁻¹) or in splits (30-50 and 50-30 lb ac⁻¹), with a second application ∼45 days after planting, and compared with an unfertilized control. Legume establishment was limited (<1%) and did not influence the results. Conventional tillage resulted in 20% less soil moisture than the two NT treatments. Nitrogen fertilization increased tiller density by 51% and 60% relative to unfertilized forages, with no difference between split and single N applications. Average forage accumulation ranged from 0.63 to 5.51 tons dry matter ac⁻¹. Overall, split N management resulted in greater forage accumulation than the unfertilized control for all tillage methods, as well as than a single early N application, except under CT. Overall, NT + herbicide-desiccated sod plus split N management enhanced cool-season annual forage biomass.

Soil testing provides golf course superintendents with the information needed to apply fertilizers at optimal rates, thereby avoiding nutrient deficiencies and unnecessary applications. However, nutrient rate recommendations vary depending on how soil test results are interpreted. Two approaches to interpreting soil test results are the Sufficiency Level of Available Nutrients (SLAN) and the Minimum Levels for Sustainable Nutrition (MLSN). Although these approaches have been compared on putting greens outside the United States, they have not yet been compared within the United States. Therefore, the objective of this study was to compare the effects of SLAN and MLSN nutrient recommendations on a ‘Penn A-4’ creeping bentgrass research putting green (Agrostis stolonifera L.) grown on a United States Golf Association–specification root zone in Michigan. The study was conducted at the Hancock Turfgrass Research Center in East Lansing, MI, from 2019 to 2021. The experimental design was a split-plot with two factors and three replications. The whole plot included three levels: SLAN, MLSN, and a nitrogen-fertilized control treatment. The subplot included two levels: trafficked and non-trafficked. Soil samples were collected in the spring and fall to a depth of 6 in. Turfgrass quality and health were measured monthly. Both approaches recommended a similar phosphorus application rate. However, MLSN recommended 200% less potassium than SLAN while maintaining comparable turfgrass quality under both trafficked and non-trafficked conditions.

Addressing Sri Lanka's vegetable sector challenges requires recognizing farmers’ problems, extension staff training needs, and researchers’ priorities. This study analyzed Department of Agriculture reports (2012–2023) covering Yala and Maha seasons across all administrative divisions in Sri Lanka. In total, 462 field problems, 793 training needs, and 216 research requirements were documented. The frequency distribution within each category and the associations between variables were analyzed using Chi-square tests. Results indicated that more field problems were reported during the Yala season (61.3%) than the Maha season (38.8%; p < 0.05). Of these, 30.5% were attributed to pests and 26.6% to diseases (p > 0.05). Moreover, extension staff failed to identify >29% of the field problems reported, resulting in delays in their resolution. Most field problems were reported for bean (Phaseolus vulgaris L.), bitter gourd (Momordica charantia L.), brinjal (Solanum melongena L.), and tomato (Solanum lycopersicum L.). Bean, brinjal, cassava (Manihot esculenta Crantz), and yard-long bean [Vigna unguiculata subsp. sesquipedalis (L.) Verdc.] showed more field problems during the Yala season (p < 0.05), whereas other crops showed no seasonal variation in reported issues (p > 0.05). Extension staff requested more training during Yala (62.2%) than during Maha (37.8%), with key focus areas including agronomy (36.5%), pest and disease management (29.1%), and soil and fertilizer management (26.1%). A greater number of research requirements also emerged during Yala (62.5%), particularly in the areas of pest and disease management (30.6%), soil and fertilizer management (26.8%), agronomy (21.7%), and crop breeding (20.4%). Overall, most field problems, training needs, and research requirements in Sri Lanka's vegetable sector are related to pest and disease management and are influenced by season, crop type, and regional context.

Including soybean [Glycine max (L.) Merr.] in the previous cropping cycle can adversely affect peanut (Arachis hypogaea L.) yield by increasing disease incidence and populations of plant-parasitic nematodes in the soil. The impact of double-cropping wheat (Triticum aestivum L.) and soybean versus full-season soybean (referred to as the soybean planting system) has not been determined for peanut. Soybean and wheat yields were not affected by diverse crop sequences that included corn, cotton, peanut, and soybean under conventional tillage. Peanut, soybean, and wheat yields were greater at one of two locations when peanut followed a crop sequence that included tall fescue in previous years compared with a crop sequence without tall fescue. Peanut yield was greater at one of two locations when grown the year after double-cropped wheat and soybean compared with full-season soybean. Root galling of peanut caused by root-knot nematode (Meloidogyne spp.) was lower at one of two locations when tall fescue was included in the previous crop sequence. Results from these experiments indicate there is less risk for lower peanut yield when wheat and soybean are double-cropped than when full-season soybean is established the year prior to peanut.

In climate change–vulnerable, food-insecure semi-arid regions of Sub-Saharan Africa, limited studies compared the performance of pearl millet [Pennisetum glaucum (L.)] landraces and improved genotypes under staggered sowing to establish their interactions, resulting in a generalization that landraces are lower yielding than their improved counterparts. A 3-year field experiment was conducted to compare grain and biomass production of an improved Okashana-2 and the landrace Kantana pearl millet genotypes under five sowing dates between January 1 and March 1 in semi-arid North-Central Namibia. Across years, Kantana sown on January 1 produced the highest grain and shoot biomass yields, ranging from 0.5 to 9.5 t ha⁻¹ and 2.6 to 31.4 t ha⁻¹, respectively, with both gradually declining with sowing delays. Higher grain and biomass yields in early-sown Kantana were due to its longer vegetative growth phase, nearly 2 weeks longer than that of its Okashana-2 counterpart, allowing more time for normal growth and development before heading. Okashana-2, on the other hand, attained its highest yields under January 1 or January 15 sowing dates, with grain and biomass yields ranging from 0.8 to 7.4 t ha⁻¹ and 1.7 to 18.6 t ha⁻¹, respectively, fluctuating among sowing dates; however, March 1 sowing produced the lowest yields. The variable yields for Okashana-2 indicate the genotype's ability to respond rapidly to soil moisture from various rainfall events. These results demonstrate that maximum pearl millet yields in northern Namibia are achievable by sowing Kantana by January 1, while Okashana-2 has higher and relatively stable yields under late sowing. However, farmers must promptly acquire production inputs and services to facilitate early sowing.

Bermudagrass (Cynodon spp.) is an important forage in the southeastern United States. Bermudagrass is incredibly diverse and includes numerous important cultivars for forage use. Most published research compares forage accumulation, nutritive value, or establishment among bermudagrass cultivars. There is a need to document bermudagrass stem diameters and to define classifications or groupings. The objectives of this study were (a) to compare the stem diameters of popular Cynodon cultivars currently grown in the southeastern United States, and (b) to assign these cultivars to defined-diameter categories. Three categories were defined based on the general stem size of popular hybrid bermudagrass cultivars and experimental genotypes. (1) Fine-stemmed cultivars have stem diameters <0.04 in. They have rapid drying times and establishment rates but exhibit poor tolerance to the bermudagrass stem maggot (BSM; Atherigona reversura Villeneuve) and tend to have lower nutritive value and production. (2) Intermediate-stemmed cultivars have stem diameters between 0.04 and 0.06 in. Many experimental genotypes fall into this category and show potential for optimizing drying time, establishment, and production capabilities. (3) Coarse-stemmed cultivars have stem diameters >0.06 in. These cultivars demonstrate documented improvements in production and BSM tolerance, but slow drying times and establishment hinder their adoption. Defining these categories will aid bermudagrass breeders and researchers to more easily classify forage-type bermudagrass germplasm in future evaluations.

The global expansion of drought stress, a major consequence of climate change, is adversely affecting crop production and resistance. This study aimed to investigate the efficacy of salicylic acid (SA) and cycocel (CCC) in mitigating the adverse effects on lemon balm (Melissa officinalis L.). The results revealed that the essential oil (EO) yield and percentage were mostly enhanced by 37% and 33%, respectively, under mild drought stress, indicating the plant's adaptive mechanism to optimize EO production under moderate stress conditions. Proline content also increased, reaching ∼2.45 µg g⁻¹ fresh wt. under severe drought with foliar application, representing a 40% increase compared with untreated plants. Similarly, the enzymatic activities of catalase and superoxide dismutase were enhanced by 26% and 30%, respectively, under the same conditions. Overall, our results suggest that SA and CCC are effective plant growth regulators for lemon balm cultivation, particularly in arid areas.

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.