Crop, Forage and Turfgrass Management最新文献

Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.; TF] is widely used in temperate pastures, but its production and nutritive value may be improved through the interseeding of complementary species such as crabgrass (Digitaria sanguinalis L.; CG) and buckhorn plantain (Plantago lanceolata L.; PL). This study aimed to evaluate the effects of TF in monoculture, TF+CG, TF+PL, and TF+CG+PL during four harvests, focusing on botanical composition, forage mass (FM), and nutritive value in Spring Hill for 2 years. Weed proportion varied throughout the study, but it was lowest (∼20%) in the TF+CG and TF+CG+PL treatments due to the increased proportion of CG observed during the third (24%) and fourth (61%) harvests. In 2022, the TF+PL and TF+CG treatments showed greater FM (2041 and 1958 dry matter [DM] lbs acre⁻¹, respectively). In 2023, the TF+CG+PL treatment recorded the lowest FM (1673 DM lbs ac⁻¹) compared to the other treatments (∼1746 DM lbs acre⁻¹). The fourth harvest showed the greatest FM in 2022 (2372 DM lbs acre⁻¹), and in 2023, both the first and fourth harvests produced the greatest FM (2154 and 1947 DM lbs acre⁻¹, respectively). Overall, there were few differences in nutritive value across treatments; however, the third harvest in both years showed greater crude protein concentration (∼14.9%) and increased neutral detergent fiber digestibility in 2022 (34.7%), with no significant differences in 2023. This study highlights the benefits of interseeding plant species with diverse traits into forage systems to enhance biodiversity. Among the species tested, CG demonstrated superior qualities, including effective weed suppression, greater FM, and improved nutritive value.

Perennial ryegrass (Lolium perenne L. ssp. perenne) seed production fields in western Oregon are often established using carbon-seeding, which consists of applying a band of activated charcoal (AC) over the seed row at the time of sowing. A preemergent herbicide is then broadcast applied to the field prior to rainfall or irrigation. In the seed row, the herbicide that encounters AC is absorbed, which allows the seed to germinate and establish. Biochar has similar characteristics to AC and is a potential alternative for carbon-seeding. Conifer-based biochars are produced in western Oregon, use less energy to make, and are less expensive than AC, providing potential benefits to stakeholders. To compare the seed row protection effects of conifer-based biochar to AC, we tested seven herbicide treatments: EPTC, diuron, indaziflam, rimsulfuron, pronamide, a combination of pyroxasulfone and flumioxazin, and a no herbicide check in a field study repeated four times in western Oregon. Results suggest that perennial ryegrass establishment was equivalent when either biochar or AC were used in combination with diuron, rimsulfuron, pronamide, and a combination of pyroxasulfone and flumioxazin signifying that biochar could be used in place of AC for these herbicides. Perennial ryegrass establishment was greater when activated charcoal was used compared to biochar when indaziflam was used. When EPTC was used, neither AC nor biochar led to perennial ryegrass establishment that was equal to the no herbicide check plots. Findings provide data on the use of biochar for carbon-seeding and an update on crop safety expectations across multiple herbicides in this system.

Methiozolin was registered for preemergence and postemergence annual bluegrass control in 2019 and offers good cool-season turfgrass safety. The methiozolin label indicates that a higher rate is required to effectively control annual bluegrass (Poa annua L.) at mowing heights greater than that of typical golf course putting greens. Additionally, the herbicide label recommends post-application irrigation for effective annual bluegrass control that is difficult to administer timely due to demands of golf play. The objective of this research was to determine the effect of mowing height and post-application irrigation on annual bluegrass control with methiozolin. Three field studies were initiated in Blacksburg, VA, on creeping bentgrass (Agrostis stolonifera L.) and Kentucky bluegrass (Poa pratensis L.) research fairways as a split-plot design, with three mowing heights (0.15, 0.30, and 0.6 inches) as main plots. Subplots were arranged as a four by two factorial with four levels of methiozolin rate (0.45–3.6 lb ai acre⁻¹) and two levels of post-application irrigation (0 and 0.2 inches). At all locations, as mowing height increased, more methiozolin was required to control annual bluegrass 80% (C₈₀). At two of the three locations, post application irrigation increased annual bluegrass control at 0.3 inches or higher heights of cut. When turf was maintained at 0.3 inches, annual bluegrass C₈₀ was reduced by approximately 50% with post application irrigation compared to no irrigation in two of the three trials. Results from these studies support product label recommendations regarding increased use rates with higher heights of cut but cannot confirm the need for post-application irrigation in putting green height turf.

This study assessed the effects of row arrangement and cropping systems on maize (Zea mays L.) agronomy and profitability in a maize–cowpea (Vigna unguiculata L.) intercropping system under field conditions in Ethiopia. A factorial combination of two cowpea varieties, TVU and White Wonder Trailing (WWT), a three-row arrangement (1 maize [M]: 1 cowpea [C], 1 M: 2C, and 1 M: 3C), and three cropping systems (sole maize, maize+WWT, and maize+TVU) were evaluated using a randomized complete block design with three replications. The results revealed that row arrangement significantly (p < 0.05) affected seeds cob⁻¹ and harvest index, with the TVU variety yielding the highest values. The 1 M: 2C arrangement with the TVU variety produced the highest harvest index value, grain, and biological yields. Overall, the traits assessed were more evident in solo cropping than in intercropping. The land equivalent ratio (LER) and area time equivalent ratio (ATER) for intercropping surpassed critical thresholds in all cases. The TVU variety achieved the highest LER and ATER in the 1 M: 2C arrangement. Additionally, the 1 M: 2C+TVU combination yielded a monetary advantage index score of $2017.35 ha⁻¹, a net benefit of $3614.22 ha⁻¹, and an acceptable marginal rate of return. Therefore, it is recommended that the TVU variety be grown in a 1 M: 2C arrangement for the study areas and similar agroecological conditions.

The turfgrass system is a complex ecosystem where many soil-born arthropods dwell and co-exist. Often, turfgrass is threatened by many pests, such as billbugs (Sphenophorus spp.; Coleoptera: Curculionidae). Monitoring pests is an important strategy for effective management decisions. The four-way linear pitfall trap is commonly used to determine adult Sphenophorus spp. population in turfgrass; however, it is challenging to deploy, labor-intensive, and requires regular intensive maintenance. The objectives of this study were to (1) compare trap captures of Sphenophorus spp. and predators using solo-cup, pail, two and four-way linear pitfall traps, and (2) evaluate whether increasing the number of simpler traps improves capture efficiency of soil-dwelling arthropods. The captures of adult Sphenophorus spp. and carabids in the four-way linear pitfall trap were not consistently greater than those caught in the two-way linear or single solo-cup pitfall traps. The four and eight solo-cup pitfall traps captured more Sphenophorus spp. and most soil-active predators than the four-way linear pitfall trap. The pail pitfall trap was not efficient in capturing soil-active arthropods. Thus, increased numbers of solo-cup pitfall traps, at least four in a defined trapping area, could be an alternative to the four-way linear pitfall trap to sample or monitor Sphenophorus spp. or carabids. Deploying and maintaining a solo cup is much easier than a four-way linear pitfall trap.

Pasture systems in the northeastern United States are primarily comprised of cool-season perennial grasses. However, these systems are subject to a lag in forage production during the hot summer months. Incorporating warm-season annual grasses (WSA) into these forage systems may improve overall forage productivity, especially for producers with a limited land base. Therefore, the objective of this study was to compare the agronomic effect of WSA interseeded into orchardgrass (Dactylus glomerata L.; OG) and harvested at two different intervals. This study compared monocultures of OG to OG interseeded with sorghum-sudangrass (Sorghum bicolor × S. bicolor var. sudanense; SSG), pearl millet (Pennisetum glaucum L.; PM) or teff grass (Eragrostis tef L.; TEFF), harvested on either a 6- or 12-week interval. Results indicated that inclusion of WSA into OG did not improve total herbage accumulation or nutritive value beyond the OG monoculture at either harvest interval (p > 0.42). However, inclusion of WSA into OG did affect the proportion of OG in the stand at both harvest intervals (p < 0.01). The greatest effect was observed in plots interseeded with SSG, in which there was a ∼14% and ∼25% decrease in OG compared to OG monoculture plots when harvested on a 6- and 12-week interval, respectively. This study concluded that interseeding WSA into OG did not improve agronomic parameters of the stand compared to OG despite implementing different harvest frequencies. Future research is warranted evaluating the effect of warm-season annual legumes under similar conditions on the forage production of cool-season perennial grass pastures.

A 2-year experiment was conducted to evaluate the efficiency of Rhizobium bacteria and arbuscular mycorrhizal fungi in improving the growth and yield-related traits of grass pea (Lathyrus sativus L.) under different irrigation regimes (well-watered, mild water stress, and severe water stress). The results showed that unfertilized and water-stressed plants had the lowest performance, while plants inoculated with bioinoculants exhibited the best growth and yield. Water limitation led to a reduction in total chlorophyll content (20.3%), leaf area index (20.32%), relative water content (5.5%), seeds/pod (2.9%), pods/plant (20.23%), 1000-seed weight (2.92%), pod harvest index (0.72%), seed yield (24.5%), and biological yield (17.69%) compared to the well-watered treatment over 2 years. Rhizobium inoculation enhanced relative water content, seeds/pod, 100-seed weight, biological yield, and pod harvest index by an average of 9.25%, 4.82%, 4.81%, 16.78%, and 1.36%, respectively. Similarly, arbuscular mycorrhizal fungi inoculation increased relative water content (7.7%), seeds/pod (3.8%), 1000-seed weight (3.9%), pod harvest index (1.04%), and pod partitioning index (13.9%). These findings suggest that applying a combination of bioinoculants from different microbial groups can be an effective strategy for enhancing the productivity of grass pea under water-limited conditions.

Selecting an appropriate relative maturity group (MG) soybean [Glycine max (L.) Merr.] for a geographic location within a state is a crucial factor in ensuring profitable soybean production. Choosing an inappropriate MG can significantly reduce yield. We determined the probability of a relative MG yielding similar to or better than the other MGs by analyzing the yield data of full-season and double-crop soybean from Official Variety Tests (OVT) that were conducted across five locations in Virginia from 2006 to 2015. We considered MGs 3 to 5 for full-season and MGs 4 to 5 for double-crop soybean. Each MG was divided into three sub-groups: early (x.0-x.3), mid (x.4-x.6), and late (x.7-x.9). While MG significantly influenced soybean yield in most site-years with few exceptions, location affected the yield performance of a MG more for full-season than double-crop soybean. For full-season soybean, late MG-3 and 4 at Orange (38.3°N, −78.1°W), early to mid-MG-5 at Warsaw (38.0°N, −76.8°W), mid to late MG-4 at Painter (37.6°N, −75.8°W), and early to late MG-5 at Blackstone (37.1°N, −78.0°W) and Suffolk (36.7°N, −76.8°W), VA, had the highest outyielding capacity and probability to yield similar to or greater than other MGs. For double-crop soybean, late MG-4 consistently performed best across most locations, except for Blackstone, where early MG-5 was the optimal choice. Results offer valuable insights to soybean producers for confidently selecting the best MG with the greatest yield probability in their farming locations within Virginia. This analysis can serve as a model for similar investigations in other states using OVT data.

Wide-spread adoption of proximal sensors in crop health assessment requires understanding of changes in canopy reflectance during the growing season and associations among readings from different sensors. Chlorophyll meter reading (Soil Plant Analysis Development, SPAD), red normalized difference vegetation index (RNDVI), and red-edge normalized difference vegetation index (RENDVI) were measured for sugarbeet (Beta vulgaris L.), corn (Zea mays), sunflower (Helianthus annuus L.), soybean (Glycine max), and spring wheat (Triticum aestivum) throughout the 2021 growing season. Cumulative growing degree days (GDD) had a significant relationship with SPAD, RNDVI, and RENDVI. The correlation coefficient indicated SPAD was more associated with RENDVI (r = 0.73) than RNDVI (0.50). The R² values of multiple linear regression of SPAD and GDD with RNDVI and RENDVI were the lowest for spring wheat (0.33 and 0.52, respectively) and the highest for corn (0.94 and 0.95, respectively). For all major five crops grown in the Northern Great Plains, GDD showed a strong relationship with all three indices. For in-season crop health assessment based on vegetation indices, inclusion of GDD could be a useful predictor variable to develop a single model algorithm applicable for multiple crops at a regional scale.