Crop, Forage and Turfgrass Management最新文献

Interest in seeded bermudagrass cultivars has increased, but there is still a lack of information on management strategies combining nitrogen (N) fertilization and harvest frequency to support producer's decision-making process in a hayfield. In this study, we evaluated how combinations of N fertilization and harvesting management affect total forage accumulation (TFA) and nutritive value in ‘Wrangler’ bermudagrass [Cynodon dactylon (L.) Pers.] for 2 years. Management strategies were combinations of N fertilization (without N, one application, or three applications) and harvesting management (once or three times). Harvesting once or three times did not affect the TFA without N fertilization (H1 and H3) or with one application (H1N1 and H3N1). However, harvesting three times with three N applications (H3N3) presented the greatest TFA (7795 lbs dry matter [DM]/acre) and greater crude protein (CP), net energy gain, total digestible nutrients, and phosphorus (P) concentration, and lesser acid detergent fiber. Consequently, the greatest CP accumulation (CPA) was found in the H3N3 as well. Therefore, associating N fertilization with more frequent harvesting can increase the TFA and CPA, and improve the forage nutritive value, which can significantly affect winter feeding costs.

Some endophytic rhizobacteria, including species producing deaminase enzymes for 1-aminocyclopropane-1-carboxylic acid (ACC) suppressing ethylene production (ACCd), form symbiosis with plant roots to enhance plant growth and stress tolerance. The objectives of this study were to determine growth-promoting effects and effective rates of inoculation with ACCd-producing Paraburkholderia aspalathi (WSF23 and WSF14) on creeping bentgrass (Agrostis stolonifera L.) performance under deficit irrigation in field conditions and effectiveness on post-stress recovery during re-watering. Turf field plots established with ‘L-93’ creeping bentgrass were inoculated with P. aspalathi strains (WSF23 and WSF14) through soil drenching either as a single strain or as a combination of both strains. After inoculation, plots were subjected to drought stress with deficit irrigation to replace 60% of the daily evapotranspiration rate, followed by re-watering for post-stress recovery. Three inoculant rates of 1.0, 1.5, and 2.0 × 10⁷ colony-forming units (CFUs) were evaluated to determine the most effective dosage to apply under field conditions. Inoculation of plants with the consortium of the two strains at 1.5 × 10⁷ CFUs was most effective in enhancing turf quality, percent green cover, normalized difference vegetation index, and dark green color index during drought stress and recovery periods. These results suggest that creeping bentgrass tolerance to drought stress and improved post-stress recovery could benefit from inoculation with P. aspalathi strains under field conditions and also ACC deaminase-producing rhizobacteria could be incorporated into turf management programs to maintain creeping bentgrass during abiotic stress conditions.

Soybean [Glycine max (L.) Merr.] planting date (PD) and maturity group (MG) selection are critical decisions for optimizing crop development and enhancing yield potential. This study examines the interaction effects of PDs and MGs on soybean yield in southern Wisconsin, utilizing a fractional replication experimental design across two growing seasons (2022 and 2023). Five PDs in 2022 and six in 2023 were tested, with 50 soybean cultivars per PD, encompassing MGs ranging from 0.3 to 2.9. Results reveal that optimal soybean yield occurred with early planting, particularly before May 20, with MGs between 1.5 to 2.9 performing best. Delayed planting led to diminished significance in MG selection for yield, but overall yield declined consistently, roughly 20 bu/acre, every 20 days beyond the May 20 PD. Practical implications suggest early planting to maximize sunlight capture and extend the seed fill period, alongside the selection of cultivars within the appropriate MG range. While this study is limited to a single location and 2-year duration, future collaborative efforts across multiple sites could provide a more comprehensive understanding of PD and MG interactions, benefiting soybean cultivation practices in diverse environments. Overall, our findings offer valuable insights for southern Wisconsin soybean farmers seeking to optimize yield and profitability in their operations.

Montana is the leading producer of field peas (Pisum sativum L.) in the United States. A density of 8 to 10 plants ft⁻² is recommended when growing field peas in that state, but this recommendation is based on work done elsewhere. Field experiments were conducted in central Montana from 2021 through 2023 and at three additional locations in the final year to determine the yield and the economically optimum plant population (EOPP) when growing field peas for grain. The semi-leafless, yellow-cotyledon variety Montech 4152 was planted at five rates (5, 7, 9, 11, and 13 pure live seed [PLS] ft⁻²) in all 3 years with two additional rates (3 and 15 PLS ft⁻²) added in the final year. A minimum plant density of 6 to 8 plants ft⁻², or planting field pea at 7 to 9 PLS ft⁻², produced a grain yield comparable to or greater than amounts produced at other seeding rates. The minimum EOPP across the six experiments ranged from 3 (2.8) to 7 (6.4) plants ft⁻², corresponding to a seeding rate of 3 to 7 PLS ft⁻². However, more weeds were observed when field pea was planted at 3 PLS ft⁻² than at higher rates in one of the experiments. A field pea density of 6 to 8 plants ft⁻² is sufficient to optimize grain yield and economic returns in Montana and similar dryland environments.

The bermudagrass stem maggot (BSM; Atherigona reversura Villeneuve) is known to have a detrimental effect on bermudagrass (Cynodon spp.). Currently, two strategically timed pyrethroid applications are recommended for BSM suppression in each harvest cycle. However, producers are interested in applying spinosad because of its residual effects for other insects or reducing the number of pyrethroid applications to cut input costs. Therefore, the objective of this study was to determine the agronomic and economic implications of one or multiple pyrethroid (zeta-cypermethrin) and/or spinosad applications on ‘Alicia’ and ‘Tifton 85’ bermudagrasses. Generally, zeta-cypermethrin treatments resulted in a greater herbage accumulation compared to the untreated control in both cultivars. Regardless of cultivar, spinosad only treatments did not improve upon the herbage accumulation observed in the untreated control. Crude protein and total digestible nutrients were not affected by insecticide treatments in either cultivar. Finally, two zeta-cypermethrin applications resulted in greater net profit compared to other insecticide treatments. These data illustrate that there is not yet an alternative for two pyrethroid applications for BSM suppression. Ongoing research and breeding efforts are focused on BSM tolerance and reduced pyrethroid usage to prevent resistance to the insecticide.

Soybean [Glycine max (L.) Merr.] biomass and grain yield has increased over the past several decades in the mid-southern United States. This is attributable to technological advances and improved management strategies. However, a better understanding of biomass accumulation and partitioning is needed to improve our knowledge base of varietal growth habits relative to yield, planting date, and harvest index (HI). Field experiments within a split plot arrangement in a randomized complete block design were established in 2017 and 2018 in Stoneville, MS. The study aimed to evaluate the effect of early (late-April or mid-May) and late (late-May) planting on biomass, HI, and yield amongst eight soybean varieties. Soybean total biomass accumulation was collected at multiple development stages, including V4, R2, mid R5, mid R6, and R8, and partitioned into senesced leaves, pods, and seeds. Overall, the planting date had no effect on yield, HI, and biomass accumulation at any of the growth stages. Yet, the interaction between planting date and variety significantly affected biomass accumulation at the mid R5 stage. Contrarily, the variety selection significantly affected yield, HI, and biomass accumulation at all growth stages except mid R6. The total biomass accumulation at R8 was greatest for Asgrow 46X6, Asgrow 4632, Terral 4857X, Terral 48A76, and Credenz 4748, when pooled over planting dates. Averaged across two planting dates, the greatest yield was produced by Terral 48A76, Asgrow 4632, and Asgrow 46X6. Furthermore, averaged across site-years, HI was greatest for Asgrow 4632 and Terral 48A76. Based on the results of this study, evaluating soybean HI rather than overall biomass accumulation may be more beneficial for variety selection decisions.

To explore the effects of varied irrigation regimes on different sorghum [Sorghum bicolor (L.) Moench] cultivars, a split-plot experiment adhering to a randomized complete block design with three replications was conducted in 2016 across the Khaveh and Varamin regions. The experimental treatments encompassed irrigation levels as the primary factor and four different sorghum cultivars as the secondary factor. Cultivars exhibiting larger leaf areas were associated with higher chlorophyll content, which enhanced biomass production and the quality of sorghum products. Notable variability in leaf area and crude fiber content was observed across irrigation regimes and cultivars, with 2121 cm² to 7153 cm² and 40.4% to 50.7%, respectively. Plant height, total dry weight, and water use efficiency were markedly higher under well-irrigated conditions than those under moderate and severe water deficit conditions. Specifically, the Pegah cultivar displayed the highest leaf area in the Varamin region, measuring 4612 cm² and 5911 cm², whereas the Thin Stem cultivar exhibited the lowest leaf area at both locations. Our findings suggest that the Pegah cultivar maintained a high leaf area without reducing total dry weight, indicating its stability across different environments. Therefore, to produce sorghums in similar climatic conditions, full irrigation is recommended. These results underscore the significance of ongoing research and breeding initiatives to leverage genetic diversity and improve sorghum cultivars.