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Cotton (Gossypium hirsutum L.) and potassium (K) dynamics are not well understood particularly in soils with high K levels. Potassium is important for cotton reproductive development as it influences the number, size, and weight of bolls and can improve fiber quality by mitigating moisture stress. In the case that soil cannot replenish solution K from exchangeable reserves to meet the plant demands, deficiencies may occur leading to decreased yield (lint and seed) and fiber quality, reduced drought and disease tolerance, and premature boll opening. Studies were conducted in 2016 and 2017 in Lubbock (Olton clay loam and Acuff loam) and Lamesa (Amarillo fine sandy loam), TX, to determine the effects of K application rates and timing on lint yield and fiber quality of modern cotton cultivars (DP 1518 B2XF, DP 1522 B2XF, DP 1321 B2XF, and DP 1612 B2XF). Pre‐plant soil tests were >250 mg K kg–1 at both locations and years at the 0‐to‐15‐cm soil depths. Potassium treatments were applied at 0 (control), 90, and 180 kg K ha–1 as pre‐plant, side‐dress, or split applications. Harvest results determined that pre‐plant and side‐dress K applications produced significantly greater lint yield only for DP 1518 B2XF at both locations, while effects on fiber quality varied by location. The response of DP 1518 B2XF to K fertilizer was due to greater K use efficiency and possibly K demand of this cultivar compared to the others. This research provides evidence for continued investigation of cultivar by environment‐based K management. Core Ideas: Lint yield of DP 1518 B2XF responded to soil K fertilizer treatment in Lamesa and Lubbock.Pre‐plant and side‐dress K applications produced greater lint yield at these locations.DP 1518 B2XF was determined to have greater K use efficiency than the other cultivars tested.Yield response to K differed depending on location, which had different textures and K levels. [ABSTRACT FROM AUTHOR]

Interseeding alfalfa (Medicago sativa L.) can improve forage quality of grasslands by adding a high‐protein species, but this runs the risk of accelerating soil water depletion. The objective was to evaluate effects of cultivar and row spacing of alfalfa on soil water balance and plant water potentials (Ψ) of two upright‐type cultivars, NuMex Bill Melton and WL 440HQ, and a prostrate‐type Falcata‐Rhizoma blend, interseeded into native grasses in October 2015 near Lubbock, Texas. Alfalfa was interseeded at 36‐cm (narrow) and 71‐cm (wide) row spacings. Soil volumetric water content (VWC) and midday Ψstem and Ψleaf were measured weekly in 2017 and 2018 growing seasons. Soil VWC was not affected by alfalfa cultivars (P >.05), whereas alfalfa row spacings differed (P <.05). Narrow spacing caused lower (P <.05) VWC than wide spacing relative to the grass‐only control in both the upper 40‐ and 40‐ to 100‐cm layers of the soil. Wide‐row spacing had similar VWC to control in 2017 for both soil layers (P >.05). Soil water depletion increased with alfalfa crown density (r =.60, P <.05) in association with enhanced evapotranspiration and denser root mass below 30‐cm soil depth. Grass and alfalfa Ψstem and Ψleaf were depressed in narrow rows relative to wide rows and control, indicating that presence of alfalfa intensified competition with the grass for soil water. The wide‐row treatment seldom had adverse effects on grass water stress. Wide‐row spacing achieved a favorable compromise between enhanced water use and improved stand productivity. [ABSTRACT FROM AUTHOR]

High evapotranspirational demand combined with poor quality irrigation water increases salinity concerns in semiarid regions. Accumulated salts in the root zone may negatively affect bermudagrass (Cynodon spp.) growth and quality. The objective of this study was to examine the effectiveness of cultivation practices combined with products to enhance fairway conditions without applying leaching water levels. Two golf courses in Lubbock, TX, were selected for this research. Cultivation practices, including noncultivated control, core aerification, and slicing, were conducted in mid-June of 2015 and 2016. Nine products recommended to enhance water movement or to disassociate sodium were applied within each cultivation treatment at label rates. Soil pH and electrical conductivity (EC) were determined from samples obtained in June, August, and October each year. Volumetric water content, visual turf quality, digital image analysis, normalized difference vegetation index, and ratio vegetation index were assessed from June to October in 2015 and 2016. Soil EC fluctuated with rainfall events. However, no treatment reduced soil EC. Gypsum-based products increased soil EC but reduced pH at the conclusion of the research. Core aerification reduced aboveground parameters at Golf Course A because aerified holes remained visible throughout summer, whereas slicing and core aerification improved turf quality and ratio vegetation index at Golf Course B. These results emphasize the need to test irrigation water for the salinity hazard before implementing management strategies and the importance of leaching by rainfall or additional irrigation. Lastly, high surface disruption cultivation practices may inhibit bermudagrass recovery on higher clay content soils. [ABSTRACT FROM AUTHOR]