Interaction Effects of Salinity and Mowing on Performance and Physiology of Bermudagrass Cultivars

Abstract

The effects of mowing management on salinity tolerance are not well understood. These effects were studied on turf quality, clipping yield, root mass, canopy photosynthetic rate (Pn), total nonstructure carbohydrate content (TNC), shoot reducing sugar content (RSC), and K+ and Na+ contents in shoots and roots of Tifgreen, Tifdwarf, and Tifway bermudagrass [Cynodon dactylon (L.) Pers.] cultivars using a hydroponic system. Increasing salinity resulted in a significant (p < 0.05) reduction in turf quality. Canopy photosynthetic rate values in Tifgreen were the highest (9.92, 12.98, and 18.91 μmol CO2 m−2 s−1 at 15, 30, and 45 mm mowing heights respectively) compared with Tifdwarf and Tifway at 20 dS m−1 Tifgreen achieved 22, 20, 21, and 32% more clipping yield than Tifway at control and 8, 16, and 20 dS m−1 salinity levels respectively under the highest mowing level. At the highest mowing height, the increase in Tifgreen, Tifdwarf, and Tifway root mass was 33, 40, and 31%, respectively, as salinity increased from control to 20 dS m−1 Total nonstructure carbohydrate content decreased by 36, 21, and 18% in Tifgreen while RSC increased by 35, 34, and 32% at 15, 30, and 45 mm mowing heights, respectively, as salinity increased from control to 20 dS m−1 Bermudagrass had the highest selectivity of K+ over Na+ when maintained at 45 mm mowing height. Tifgreen showed significantly (p < 0.05) higher salinity tolerance compared to other tested cultivars, and the capability of bermudagrass cultivars to survive salinity stress can be enhanced by increasing mowing height.

Soil Salinity of an Urban Park after Long‐Term Irrigation with Saline Ground Water

“…Estimation of visual coverage indicated that sparsely covered or bare soil areas in the northern and western parts of the park matched the areas with the highest salinity levels of 15 dS m -1 or higher. These observations support findings of Shaba (2010) and Marcum and Pessarakli (2006), who reported a threshold level of 15 dS m -1 at which bermudagrass drops below a rating of 6 for visual quality (Shahba, 2010) or reduces growth by 50% (Marcum and Pessarakli, 2006). Our observations also support findings of Xiang et al (2017) who documented a drop in live green cover for several bermudagrasses from greater than 80% at EC ≤ 15 dS m -1 to less than 50% at EC ≥ 15 dS m -1 .…”

“…Soil texture of subsamples was determined using the hydrometer method (Gee and Or, 2002). Processed soil samples were analyzed for salinity (EC e ) (Rhoades, 1996); and concentrations of Na, Ca, and Mg using ion chromatography (Helmke and Sparks, 1996;Suarez, 1996). Sodium adsorption ratios of the samples were estimated from Ca, Mg, and Na concentrations (Essington, 2003).…”

Nitrogen fertilization of warm‐season turfgrasses irrigated from varying irrigation systems: 2. Carbohydrate and protein content

“…An increase in fructose content as a result of increased salinity was also found in wheat seedlings (Kerepesi & Galiba, ) and in creeping bentgrass seedlings (Qian & Fu, ). However, the levels of soil salinity documented in our study may not have created sufficient salt stress compared to what has been reported from greenhouse or growth chambers studies (Shahba, ; Shahba, Alshammary, & Abbas, ).…”

Seaweed Extracts Enhance Salam Turfgrass Performance during Prolonged Irrigation Intervals and Saline Shock

“…Goyal and Thind (2015) reported an enhanced sugar content in SWE treated rice, also Ciepiela et al (2016) found significant increases in TNC composition in fodder grass treated with Ecklonia maxima SWE. Salinity leads to the significant reductions of TNC as well as increases in reducing sugars in different turfgrasses (Qian and Fu, 2005; Shahba, 2010; Shahba et al, 2012). For example, Qian and Fu (2005) reported a reduction in TNC from 123.8 to 89.4 mg·g −1 dry wt when salinity increased from 0.2 dS·m −1 (tap water) to 15 dS·m −1 , respectively and they suggested that such reduction because TNC serves as a resource for the reduced sugars which normally increase under saline conditions.…”