Search Results (87)

Field bindweed (Convolvulus arvensis L.) is a competitive herbaceous perennial weed that reduces productivity in irrigated pastures. Grazing might reduce competition by field bindweed when it begins growth in the spring, thereby encouraging encroachment by desirable grass species during the summer. To test this hypothesis, a two-year study was conducted in two adjacent, privately owned, irrigated, warm-season perennial grass pastures (replicates) that were heavily infested with field bindweed. Study sites were near Tucumcari, NM, USA. The fields were grazed with exclosures to evaluate ungrazed management. Aboveground biomass of field bindweed, other weeds, and perennial grass were measured, and field bindweed plants were counted in May of 2018 and 2019. There was no difference between years for any variable. Other weed biomass and field bindweed biomass and plant numbers were reduced (p < 0.05) by grazing (61.68 vs. 41.67 g bindweed biomass m⁻² for ungrazed and grazed management, respectively, and 108.5 and 56.8 bindweed plants m⁻² for ungrazed and grazed management, respectively). Otherwise, perennial grass production was unaffected by either year or management. These results indicate that grazing can be an effective tool to reduce field bindweed competition in warm-season perennial grass pastures. Full article

Interest in using warm-season grasses, including switchgrass (SG) (Panicum virgatum L.), as a bioenergy crop has increased in Europe. This study evaluated the effects of harvesting regimes with two cuts per year on the productivity, chemical composition and biochemical methane potential of the SG cultivars ‘Dacotah’, ‘Foresburg’ and ‘Cave in Rock’ in environments with cool and moderate climates in Europe with minimal fertilizer application. The results of two harvest years suggest that the biomass yield, chemical composition and energy potential depend on the grass cultivars and harvesting time. Significant effects (p < 0.05) of the harvest date and cultivar were observed for most of the measured parameters for biomass and silage quality. All three SG cultivars harvested on August 8 produced the lowest (p < 0.05) volume of methane per kg of biomass (181–202 normal litres (NL) per kg⁻¹ volatile solids (VS)) compared to the biomass of the respective cultivar harvested on 14 July (287–308 NL kg⁻¹ VS) or on October 3, as regrowth after the first cut made in mid-July (274–307 NL kg⁻¹ VS). The stands of all three SG cultivars, when the first harvest was completed in mid-July, achieved a higher annual area-specific methane yield than those harvested first in August (1128–1900 Nm³ ha⁻¹ and 888–1332 Nm³ ha⁻¹, respectively). Depending on the harvest regime and cultivar, the annual gross energy presented as a lower heating value varied from 31.8 GJ ha⁻¹ to 68.0 GJ ha⁻¹. It is concluded that SG growing under the cool temperate climate of Northern Europe could be an interesting alternative crop for methane production. Our study proves that the cultivar choice also plays an important role. Full article

The pasture–animal interface of warm-season perennial grass–legume mixed pastures has never been investigated in forage-based equine systems. Therefore, this 2-year study investigated the herbage and animal responses under 84-day continuous stocking in mixed pastures of rhizoma peanut (RP, Arachis glabrata Benth) and bahiagrass (BG, Paspalum notatum Flüggé) with 30 kg nitrogen (N) ha⁻¹ (BG-RP) compared to BG pastures fertilized with 120 kg N ha⁻¹ (BG-N₁₂₀) and no N (BG-N₀). Measurements were taken every 14 days, except for intake and in vivo digestibility, which were measured every 28 days. BG-N₁₂₀ had the highest stocking rate (p = 0.01; 3.7 AU ha⁻¹) in 2019, while BG-N₀ had the lowest (p = 0.01; 2.6 AU ha⁻¹) in 2020. Crude protein and digestible energy were greatest (p < 0.05) for BG-N₁₂₀ and BG-RP in some of the evaluation days in 2019 but similar across pastures in 2020. Crude protein digestibility was greatest (p < 0.05) for BG-RP in the late season. Intake was less (p = 0.03) for horses grazing BG-RP (3.2%BW) compared to BG-N₀ (5.0%BW). Nonetheless, no differences (p > 0.05) were observed among pastures for body measurements. The results indicate that BG-RP pastures can improve forage nutritive value and maintain horse body condition while maintaining similar stocking rate to monoculture bahiagrass with high N fertilizer rates. Full article

Interseeding pastures with annual warm-season grasses may increase forage accumulation and nutritive value. Our objective was to evaluate the effects of seeding rates of crabgrass [Digitaria ischaemum (Schreb.) Schreb. Ex Muhl], sorghum–sudangrass (Sorghum bicolor × S. bicolor var. sudanense), and teff [Eragrostis tef (Zuccagni) Trotter] on the forage accumulation and nutritive value of pastures of smooth bromegrass (Bromus inermis Leyss.), an introduced perennial cool-season grass cultivated for pasture and hay production in the U.S. Western Corn Belt. In spring, before interseeding, forage accumulation averaged 4.03 and 6.39 Mg ha⁻¹ in 2020 and 2021, respectively. In summer, after interseeding, forage accumulation averaged 3.52 Mg ha⁻¹ in 2020 but was not affected by treatment. In 2021, forage accumulation averaged 6.22 Mg ha⁻¹ in sorghum–sudangrass interseeded stands compared to 4.08 Mg ha⁻¹ in non-seeded smooth bromegrass. Interseeding crabgrass and teff had limited effects on forage accumulation and nutritive value. Increasing the seeding rate of sorghum–sudangrass linearly increased yield of crude protein, total digestible nutrients, and dry matter. In the next spring, forage accumulation averaged 8.01 Mg ha⁻¹, and the stands showed no residual effects of the one-time interseedings. Sorghum–sudangrass proved to be the optimum annual warm-season grass for interseeding. Full article

Data are needed to identify optimum response to potassium (K) and phosphorus (P) amendment and associated mycorrhizal colonization for native warm-season grasses (NWSGs; big bluestem [BB; Andropogon gerardii Vitman] and switchgrass [SG; Panicum virgatum L.]). To evaluate these responses, experiments were conducted in Knoxville and Springfield, Tennessee, from 2013 to 2019. In twice-annual harvests, we assessed BB and SG dry matter (DM) yield, crude protein (CP), total digestible nutrients (TDNs), P and K removed by grasses (removal), and soil test P and K in response to P (29 to 88 kg ha⁻¹) and K (70 to 257 kg ha⁻¹) elemental rates, and rates of root colonization by mycorrhizal fungi in response to P. Amendments had no effect (p > 0.05) on DM yield, CP, or TDN for either species. Yield, CP, and TDN fluctuated among years (p < 0.001) for both species, but no consistent temporal trends were observed. Although removal exceeded inputs at the control (no input) for P and K, and at 70 kg K ha⁻¹, there was not an associated reduction in soil test K and P values. Phosphorus rate affected (p = 0.02) total mycorrhizal colonization, with an average of 62% colonization across both species and 70% at the highest P rates. Given the lack of response for yield, CP, TDN, or associated soil nutrient test levels, NWSGs appear to offer a low-input option for forage production. Full article

The yak industry constitutes a pivotal segment of livestock development across the Qinghai–Tibetan Plateau and adjacent pastoral regions. Existing studies have shown that supplemental feeding for grazing yaks significantly improves meat quality and growth performance, but its effect on enteric methane (CH₄) emission from yaks has never been reported, so the present experiment aimed to investigate the effect of supplemental feeding of grazing yaks on CH₄ emissions in three different periods of the warm season. Thirty male yaks were randomly assigned to two groups, with 15 yaks per group, The groups were designated as the grazing group (GR), with traditional grazing methods and with an initial body weight of 94.56 ± 3.9 kg, and the supplemental feeding group (GRS) with an initial body weight of 95.01 ± 4.1 kg, which received 1500 g/d of supplemental feed for 120 days. The methane emissions of the two groups were measured at the late regreening period (LRP), the greening-grass period (GGP), and the browning period (BRP) using the SF₆ tracer method. The results showed that GRS increased (p < 0.01) the total DMI during warm season but decreased (p < 0.01) the forage intake at the LRP and GGP, resulting in a significantly reduced methane yield per kg of BW gain and per kg of DMD in warm-season grazing yaks (p < 0.01), a significantly reduced methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the GGP (p < 0.05), and a similarly significantly decrease in methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the BRP (p < 0.01). In conclusion, supplemental nutrition for grazing yaks during the warm season in alpine grasslands significantly enhances growth performance, reduces methane emissions, and improves dietary energy utilization efficiency. Full article

Bermudagrass (Cynodon dactylon L.) is a warm-season grass species of significant ecological and economic importance. It is widely utilized in turf management and forage production due to its resilience to drought, salt, and other environmental stresses. Recent advancements in molecular breeding, particularly through genomics technology and gene editing, have enabled the efficient identification of key genes associated with stress tolerance and turf quality. The use of techniques such as overexpression and CRISPR/Cas has enhanced resistance to drought, salt, cold, and heat, while the application of molecular markers has accelerated the development of superior varieties. The integration of multi-omics, such as genomics, transcriptomics, and proteomics, provides deeper insights into the molecular mechanisms of bermudagrass, thereby improving breeding efficiency and precision. Additionally, artificial intelligence is emerging as a powerful tool for analyzing genomic data, predicting optimal trait combinations, and accelerating breeding processes. These technologies, when combined with traditional breeding methods, hold great potential for optimizing bermudagrass varieties for both turf and forage use. Future research will focus on further integrating these tools to address the challenges of breeding posed by climate change to breeding climate-resilient turf and forage crops. Full article

With global warming, the cultivation area of bermudagrass is moving northwards in the Mediterranean area despite its winter dormancy and loss of green color. The most common solution is overseeding with perennial ryegrass, which can be complicated to remove in spring. DLF breeders have released a new cultivar of annual ryegrass that is stress tolerant and easy to transition in spring. A trial was carried out on a sod farm in Pisa, Italy. Twenty-nine varieties of cool-season grasses, encompassing both forage and turf species, were overseeded on a hybrid bermudagrass variety ‘Tifway’ (Cynodon dactylon x transvaalensis). The aim of this trial was to compare the overseeding potential of various cool-season turfgrass species and cultivars and to identify which ones perform best in terms of cleanness of cut when overseeded on hybrid bermudagrass in autumn and maintained at a mowing height of 25 mm. Moreover, the following parameters were also assessed: actual turf height (cm); cumulated height (cm); turf visual color and quality (1–9 scale); and visual ground cover (%). Plots were managed with an autonomous mower, which adopted a daily mowing frequency and was set to work with systematic trajectories. The results showed differences between cultivars, and the annual ryegrass showed the best spring transition (scoring a mean value of 96% green cover in July 2023) compared to the other entries. The best result of CoC was measured for rough-stalked meadow grass ‘Sabrena 1’ and tall fescue ‘Turfway’ with 0.9 mm. Full article

Pollinator declines and expectations for more sustainable agriculture, including pasture-based enterprises, bring attention to strategies to enhance the habitat value of grazing lands. We evaluated native warm-season grass (NWSG) pastures with (FORB) and without (CONT) interseeded native forbs in 2021–2023. An analysis was conducted using R with the significance set at p ≤ 0.05. The grass appeared to be weakened predominantly by grazing management practices. Forb density and mass had an inverse relationship in seasons two and three. Total forage mass declined in response to increased grazing days and weakened stands. The forage nutritive compositions differed, with more stable, season-long crude protein and lower fiber concentrations in late-season FORB, which supported higher bodyweight gains and season-long average daily gain. Black-eyed Susan (Rudbeckia hirta; BESU), lanceleaf coreopsis (Coreopsis lanceolata; LCOR), and showy ticktrefoil (Desmodium canadensis; STTF) were the most abundant forbs, and BESU, LCOR, and purple coneflower (Echinacea purpurea; PURC) produced long flowering windows. Cattle grazed STTF, cup plant (Silphium perfoliatum; CUPP), and oxeye sunflower (Helopsis helianthoides) the most. Under continuous stocking, a blend of BESU, LCOR, PURC, STTF, and CUPP produced acceptable cattle gains and provided pollinator resources, suggesting that this model may be a viable means to enhance the sustainability of pastures. Full article

Sudan grass (Sorghum sudanense S.) is a warm-season annual grass with high yield, rich nutritional value, good regeneration, and tolerance to biotic and abiotic stresses. However, prolonged drought affects the yield and quality of Sudan grass. As one of the largest families of multifunctional transcription factors in plants, MYB is widely involved in regulating plant growth and development, hormonal signaling, and stress responses at the gene transcription level. However, the regulatory role of MYB genes has not been well characterized in Sudan grass under abiotic stress. In this study, 113 MYB genes were identified in the Sudan grass genome and categorized into three groups by phylogenetic analysis. The promoter regions of SsMYB genes contain different cis-regulatory elements, which are involved in developmental, hormonal, and stress responses, and may be closely related to their diverse regulatory functions. In addition, collinearity analysis showed that the expansion of the SsMYB gene family occurred mainly through segmental duplications. Under drought conditions, SsMYB genes showed diverse expression patterns, which varied at different time points. Interaction networks of 74 SsMYB genes were predicted based on motif binding sites, expression correlations, and protein interactions. Heterologous expression showed that SsMYB8, SsMYB15, and SsMYB64 all significantly enhanced the drought tolerance of yeast cells. Meanwhile, the subcellular localization of all three genes is in the nucleus. Overall, this study provides new insights into the evolution and function of MYB genes and provides valuable candidate genes for breeding efforts in Sudan grass. Full article

Perennial warm-season grasses typically have reduced seed yield, making it essential to identify the critical seed yield components. An induced increase in nitrogen could help determine which components are most limiting. This research aimed to estimate seed yield components in Paspalum; evaluate N fertilization effects on the reproductive phase, seed yield components, and seed quality; and establish the pattern of seed shattering over time. Nine genotypes covering different reproductive periods were used. The experimental design was a randomized complete block design in a split-plot arrangement with three replications. The main plots had two nitrogen levels (0 and 150 Kg N ha⁻¹), and the sub-plots contained different genotypes. Seed yield variation was mainly related to reproductive tiller density among germplasm with different flowering periods. Early-flowering germplasm showed an extended flowering period (159%), greater tiller density (27.7%), greater reproductive tiller density (157%), and higher yield (302%) in response to nitrogen fertilization. Seed-quality traits and seed retention were not affected by nitrogen fertilization. Seed retention over time followed an inverted sigmoid pattern, though there was considerable variation among taxonomic groups. Early-flowering germplasm exhibited superior seed retention. Seed yield in Paspalum is mainly influenced by the density of reproductive tillers and seed retention. Full article

Limpograss (Hemarthria altissima) is a warm-season perennial grass that has the potential to feed livestock during scarcity periods. This study evaluated the intake, nutrient digestibility, and animal performance of beef heifers fed ‘Gibtuck’ limpograss silage combined with different levels of a range cube supplementation. Twenty-four heifers (330 ± 16 kg live weight) were submitted to four different treatments with 6 replicates: (1) control, no supplementation + limpograss silage ad libitum; (2) 1.4 kg of supplement + limpograss silage ad libitum; (3) 2.8 kg of supplement + limpograss silage ad libitum; and (4) 4.2 kg of supplement + limpograss silage ad libitum. The apparent total tract digestibility of dry matter, organic matter, and crude protein showed a positive quadratic effect with increasing supplementation levels (p = 0.001, p = 0.002, and p < 0.0001, respectively). Overall, the supplement improved diet digestibility and total DM intake but reduced silage intake, indicating a combined effect (substitutive and additive effect) of the protein supplement. The increasing level of protein supplement increased the average daily gain with a quadratic effect (p ≤ 0.0001). Limpograss silage associated with supplementation can improve diet digestibility and increase the animal performance of growing heifers, providing an alternative for livestock in North Florida. Full article

Utilizing the potential of crops to suppress weeds is an important strategy for sustainable management. Feathertop Rhodes grass (FTR) (Chloris virgata Sw.) is a problematic warm-season weed in Australia that has recently expanded into colder seasons. This study investigated the growth and seed production of FTR at two planting times (May and July) and three wheat planting densities (0, 82, and 164 plants m⁻²) using a neighborhood design over two years. In both years, the plant height, tiller production, and panicle production of FTR were lower in the presence of wheat compared to when wheat was absent. Surrounding FTR with wheat delayed its pinnacle emergence, varying from 1 to 6 days in the first year and 4 to 21 days in the second year, depending on the planting date and wheat density. During both years and planting times, wheat’s presence caused approximately a 99% decrease in the dry matter and seed production of FTR compared to wheat’s absence. Additionally, the wheat height, an important competitive factor, was higher at both densities in the May planting compared to the July planting. The emergence, establishment, and continuous production of FTR seeds throughout the year indicate that inadequate management could result in the further spread of this weed. Our findings suggest that adjusting the date and density of wheat planting could be a viable strategy for sustainably managing this weed during colder seasons. Full article

Turfgrasses are essential landscape plants with social, environmental, and aesthetic services for urban ecosystems. However, more is needed to know how to establish them so that they can benefit from their ecosystem services in urban environments. This research examined some quality and morphological and physiological factors for the establishment and social and environmental service assessment of three warm-season turfgrasses, including Kikuyu grass (Pennisetum clandestinum), bermuda grass (Cynodon dactylon), and buffalo grass (Buchloe dactyloides), compared to the cool-season grass of tall fescue (Festuca arundinacea Schreb.). The experiment was split-plot in time, based on a randomized complete block design with eight replications. The main plot was the season with four levels, and the subplot was the four turfgrass species types. The results indicated that seasons and turfgrass types and their interaction significantly impacted most measured variables (p ≤ 0.01). Some quality measurements like turf density, color, texture, coverage, and quality after clipping and establishment confirmed the superiority of Buchloe dactyloides over the other species. Also, kikuyu grass showed higher turfgrass density, more potential for weed control, and higher coverage and growth rate but also showed invasiveness features. Tall fescue had the lowest visual aesthetic compared with the other turfgrass species. Warm-season turfgrasses adaptable to the ecology of the region should be used compared to tall fescue to achieve better turfgrass quality and social and ecosystem services for the sustainable development of arid urban environments. Full article

Many cool-season pastures in the southeastern U.S. are dominated by a competitive cool-season grass, tall fescue (Schedonorus arundinaceus), and lack substantial plant diversity. Planting native warm-season grasses (NWSGs) and wildflowers (WFs) into these pastures could provide summer forage for cattle and more floral resources for pollinators. This paper summarizes field experiments designed to evaluate different spatiotemporal planting arrangements of NWSGs and WFs to improve their establishment success. The study was conducted from April 2021 to October 2023 in central Virginia (USA). Planting treatments included NWSG and WF mixtures planted: (1) together in the same space, (2) spatially separated in space (i.e., side by side), or (3) temporally separated where NWSGs and WFs were planted in difference sequences. Results showed few differences in forage mass, floral production, and botanical composition as well as stand density in 2021 and 2022. In 2023, NWSG abundance was greater where grasses were planted first or mixed with WFs. Similarly, the WF component was favored when they were planted before NWSGs. Overall, planting NWSG and WF mixes separately, either spatially or temporally, favors successful establishment and could offer more flexibility for using selective herbicides to suppress the heavy weed pressure that often accompanies these plantings. Full article