Analysis of natural variation in bermudagrass (Cynodon dactylon) reveals physiological responses underlying drought tolerance

PLoS One. 2012;7(12):e53422. doi: 10.1371/journal.pone.0053422. Epub 2012 Dec 28.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / genetics*
  • Antioxidants / metabolism
  • Carbohydrates / analysis
  • Cynodon / chemistry
  • Cynodon / genetics*
  • Cynodon / metabolism
  • Cynodon / physiology
  • Dehydration / genetics*
  • Droughts*
  • Genetic Variation / physiology*
  • Proline / analysis
  • Reactive Oxygen Species / metabolism
  • Species Specificity
  • Stress, Physiological / genetics
  • Water-Electrolyte Balance / genetics
  • Yukon Territory

Substances

  • Antioxidants
  • Carbohydrates
  • Reactive Oxygen Species
  • Proline

Grants and funding

This research was supported by “the Hundred Talents Program”, the Knowledge Innovative Key Program of Chinese Academy of Sciences (Grant No. 54Y154761O01076) to Z. Chan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.