Analysis of Natural Variation in Bermudagrass (Cynodon dactylon) Reveals Physiological Responses Underlying Drought Tolerance

Abstract

Bermudagrass (Cynodon dactylon) is a widely used warm-season turfgrass and one of the most drought tolerant species. Dissecting the natural variation in drought tolerance and physiological responses will bring us powerful basis and novel insight for plant breeding. In the present study, we evaluated the natural variation of drought tolerance among nine bermudagrass varieties by measuring physiological responses after drought stress treatment through withholding water. Three groups differing in drought tolerance were identified, including two tolerant, five moderately tolerant and two susceptible varieties. Under drought stress condition, drought sensitive variety (Yukon) showed relative higher water loss, more severe cell membrane damage (EL), and more accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA), while drought tolerant variety (Tifgreen) exhibited significantly higher antioxidant enzymes activities. Further results indicated that drought induced cell injury in different varieties (Yukon, SR9554 and Tifgreen) exhibited liner correlation with leaf water content (LWC), H2O2 content, MDA content and antioxidant enzyme activities. Additionally, Tifgreen plants had significantly higher levels of osmolytes (proline level and soluble sugars) when compared with Yukon and SR9554 under drought stress condition. Taken together, our results indicated that natural variation of drought stress tolerance in bermudagrass varieties might be largely related to the induced changes of water status, osmolyte accumulation and antioxidant defense system.

Improved abiotic stress tolerance of bermudagrass by exogenous small molecules

“…Analysis of natural variations of drought stress tolerance revealed that different bermudagrass cultivars exhibited varied tolerance to drought stress. [1][2][3] Exogenous application of small molecules could effectively alleviate damages caused by multiple abiotic stresses, including drought, salt and cold. [4][5][6][7][8] Exogenous ABA treatment improved drought stress tolerance in 'TifEagle' cultivar through induction of H 2 O 2 and NO, which, in turn, enhanced antioxidant enzyme activities.…”

“…9 Further studies showed that abiotic stress treatments changed antioxidant enzyme activities, ROS contents, osmoprotectant contents (sugar, sucrose, dehydrin, proline), and photosynthesis. [1][2][5][6][10][11][12][13][14] Recently, proteomics and metabolomics approaches have been successfully used to detect omic level changes during bermudagrass stress responses. Under water-deficit condition, 32 proteins had increases in the abundance and 22 proteins exhibited decreases in the abundance, which were mainly involved in metabolism, energy, cell growth/division, protein synthesis and stress defense.…”

Screening of salt-tolerance potential of some native forage grasses from the eastern part of Terai-Duar grasslands in India

“…Hierarchical cluster analysis was performed using the CLUSTER 3.0 program by the uncentered matrix and complete linkage method following the protocol of de Hoon et al (2004). The resulting tree figure was displayed using the software package, Java Treeview, as described by Chan et al (2012).…”

Identification and Evaluation of Cellular and Biochemical Changes in Responses to Desiccation Tolerance in Cheilanthes Albomarginata Fern

“…In addition, the electrical conductivity of Milli-Q water (E3) was also measured. The REL was calculated using the equation: REL (%) (E1 -E3)/ (E2 -E3) × 100% [26].…”