Scientific Research and Essays

  • Abbreviation: Sci. Res. Essays
  • Language: English
  • ISSN: 1992-2248
  • DOI: 10.5897/SRE
  • Start Year: 2006
  • Published Articles: 2754

Full Length Research Paper

Response to heat stress in warm season and cool season turf grass cultivars

Suping Zhou* and Abraham Abaraha
Institute of Agricultural and Environmental Research, Tennessee State University, Nashville, TN 37209.
Email: [email protected]

  •  Accepted: 19 March 2007
  •  Published: 30 April 2007

Abstract

In this study, we investigated differences between cool-season and warm season grasses when exposed to heat stress. The results show that Kentucky blue seed germination rate was the highest at 25oC (40-50%), decreased significantly at 30oC (23-30%) and dropped to 0 at 40oC. For the Bermuda cultivars, seed germination rate was two fold higher at 30oC then 25oC, and reached the highest at 40oC. The cool season perennial rye and Bent grass seeds germinated well between 25 and 30oC. Their germination rate was significantly lower at 40oC. After exposure to 38oC for 2 d, the chlorophyll content decreased significantly for Bermuda cultivars, remained stable for Bent grass and perennial rye, and increased to the greatest extentfor Kentucky blue. Leaf soluble protein contents increased significantly for Kentucky Blue, but remained stable for most of the other cultivars. Western blot with Hsp70 and dehydrin antibodies identified that the Bermuda cultivars had a dynamic changes in the profile of the heat and dehydration stress-related proteins. No similar changes were detected in Kenblue cultivars. High temperature induced dehydrin homolog proteins, but not the Hsp 70 in Perennial rye and Bent grass cultivars. Findings from this research can be used to differentiate cool season and warm season grass cultivars in terms of germination and survival ability under high temperature.

 

Key words:  seed germination, chlorophyll content, leaf soluble protein, heat shock protein, dehydrin protein.