Drought is a major limiting factor for sustainable turfgrass management in the United States. Climate prediction models indicate that the world may experience increased global temperatures, decreased precipitation, and an increase in the occurrence and persistence of drought periods over the next century. A growing challenge facing the turfgrass industry is limited availability of water for irrigation (Snow, 2001). Thus, understanding the mechanisms of drought resistance is increasingly important for turfgrass breeders and managers.
Dehydrins are the late embryogenesis abundant (LEA) D 11 family of hydrophilic proteins with a wide range of molecular masses from 9 to 200 kDa (Close, 1996). They accumulate in plants in response to environmental influence with a dehydration component such as drought, salinity, and low temperature (Beck et al., 2007; Close, 1997). These proteins have been postulated to stabilize macromolecules or cellular structure and help to maintain the integrity of cell membranes against dehydration (Beck et al., 2007; Bray, 1997; Campbell and Close, 1997; Close, 1997). Most work with dehydrins in turfgrass has been completed in cold acclimation and freezing tolerance (Gatschet et al., 1994; Patton et al., 2007; Zhang et al., 2008, 2011). There are also studies reporting that dehydrins are present in turfgrass when drought-stressed (Hu et al., 2010; Jiang and Huang, 2002; Pan et al., 2013; Volaire, 2002). Very few data exist in turfgrass that support the popular hypothesis that dehydrin accumulation is positively correlated with dehydration tolerance. Hu et al. (2010) reported that accumulation of 31- and 40-kDa dehydrins may contribute to drought tolerance in bermudagrass through investigating four hybrid bermudagrasses (Cynodon dactylon × Cynodon transvaalensis) and four common bermudagrasses (C. dactylon).
Bermudagrass, the most important warm-season turfgrass grown in the southern portion of the United States, is regarded as a drought-resistant species (McCarty and Miller, 2002) with genotypic variation in drought resistance. Its drought resistance mechanisms include drought avoidance and drought tolerance. Some bermudagrasses have growth features such as deeper root systems, thicker cuticles, and smaller stomatal openings, which can improve their drought avoidance (Carrow, 1995, 1996; Qian et al., 1997). Others can sustain biochemical and physiological processes during internal water deficits (Hu et al., 2010; Huang et al., 1997). Different drought resistance mechanisms among bermudagrass cultivars may exhibit different patterns of dehydrin expression in response to drought stress. Three cultivars of bermudagrass selected for this study were two common bermudagrass cultivars, Celebration and Premier, and a clonally propagated hybrid cultivar developed by Oklahoma State University, Latitude 36. Several researchers have reported that ‘Celebration’ is a top-performing drought-resistant cultivar with a deep root system, whereas ‘Premier’ has high visual quality but is a drought-sensitive cultivar (Baldwin et al., 2006; Poudel, 2010; Steinke et al., 2009). ‘Latitude 36’, tested as OKC1119, was an excellent performer among all cultivars in the 2007 to 2011 National Turfgrass Evaluation Program (NTEP) bermudagrass test and had high turf quality rating (NTEP, 2013). However, there are few reports on the drought resistance mechanisms associated with dehydrin protein expression during drought stress. Investigations concerning the physiological bases of cultivar differences in drought resistance would provide valuable selection information for turfgrass breeders and managers. The objectives of this study were to investigate physiological changes in three bermudagrass cultivars under well-watered conditions and drought stress, to determine expression differences in soluble protein and dehydrin of three cultivars under well-watered and drought stress conditions, and to identify the association between dehydrin proteins and drought tolerance.
BaldwinC.M.LiuH.McCarryL.B.BauerleW.L.TolerJ.E.2006Response of six bermudagrass cultivars to different irrigation intervalsHortTechnology16466470
BeckE.H.FettigS.KnakeC.HartigK.BhattaraiT.2007Specific and unspecific responses of plants to cold and drought stressJ. Biosci.32501510
BradfordM.M.1976A rapid and sensitive method for the quantification of microgram quantities of protein utilizing the principle of a protein-dye bindingAnal. Biochem.72248254
BremerD.J.2003Evaluation of microlysimeters used in turfgrass evapotranspiration studies using the dual-probe heat-pulse techniqueAgron. J.9516251632
CarrowR.N.1995Drought resistance aspects of turfgrasses in the southeast: Evapotranspiration and crop coefficientsCrop Sci.3516851690
CloseT.J.FentonR.D.MoonanF.1993A view of plant dehydrins using antibodies specific to the carboxy terminal peptidePlant Mol. Biol.23279286
DamervalC.VienneD.D.ZivyM.ThiellementH.1986Technical improvements in two-dimensional electrophoresis increase the level of genetic variation detected in wheat-seedling proteinsElectrophoresis75254
DavidsonW.S.JonasA.ClaytonD.F.GeorgeJ.M.1998Stabilization of alpha-synuclein secondary structure upon binding to synthetic membranesJ. Biol. Chem.27394439449
EmmonsR.D.2000Turfgrass science and management. 3rd Ed. Delmar Albany NY
GatschetM.J.TaliaferroC.M.AndersonJ.A.PorterD.R.AndersonM.P.1994Cold acclimation and alterations in protein synthesis in bermudagrass crownsJ. Amer. Soc. Hort. Sci.119477480
HuL.WangZ.DuH.HuangB.2010Differential accumulation of dehydrins in response to water stress for hybrid and common bermudagrass genotypes differing in drought toleranceJ. Plant Physiol.167103109
HuangB.DuncanR.R.CarrowR.N.1997Drought-resistance mechanism of seven warm-season turfgrasses under surface soil drying: I. Shoot responseCrop Sci.3718581863
KangH.ParkK.SaltveitM.E.2005Chilling tolerance of cucumber (Cucumis sativus) seedling radicles is affected by radicle length, seedling vigor, and induced osmotic-and heat-shock proteinsPhysiol. Plant.124485492
KoagM.FentonR.D.WilkensS.CloseT.J.2003The binding of maize DHN1 to lipid vesicles. Gain of structure and lipid specificityPlant Physiol.131309316
LabhililiM.JoudrierP.GautierM.F.1995Characterization of cDNAs encoding Triticum durum dehydrins and their expression patterns in cultivars that differ in drought tolerancePlant Sci.112219230
LarssonK.E.NyströmB.LiljenbergC.2006A phosphatidylserine decarboxylase activity in root cells of oat (Avena sativa) is involved in altering membrane phospholipid composition during drought stress acclimationPlant Physiol. Biochem.44211219
LopezC.G.BanowetzG.M.PetersonC.J.KronstadW.E.2003Dehydrin expression and drought tolerance in seven wheat cultivarsCrop Sci.43577582
McCartyL.B.MillerG.2002Managing bermudagrass turf: Selection construction cultural practices and pest management strategies. Sleeping Bear Press Chelsea MI
National Turfgrass Evaluation Program2013Bermudagrass data. 4 June 2013. <http://www.ntep.org/bg.htm>
PattonA.J.CunninghamS.M.VolenecJ.J.ReicherZ.J.2007Differences in freeze tolerance of zoysiagrass: I. Role of proteinsCrop Sci.4721622169
PoudelB.P.2010Testing of clonal bermudegrass cultivars and experimental genotypes for differences in drought performance. MS thesis Oklahoma State Univ. Stillwater OK
SnowJ.T.2001Water conservation on golf courses. 4 June 2013. <http://www.usga.org/course_care/articles/environment/water/Water-Conservation-on-Golf-Courses>
SteinkeK.ChalmersD.R.ThomasJ.C.WhiteR.H.2009Summer drought effects on warm-season turfgrass canopy temperaturesAppl. Turfgrass Sci.doi: 10.1094/ATS-2009-0303-01-RS. 4 June 2013. <http://www.plantmanagementnetwork.org/sub/ats/research/2009/Canopy/Canopy.pdf>.
VolaireF.2002Drought survival, summer dormancy and dehydrin accumulation in contrasting cultivars of Dacylis glomerataPhysiol. Plant.1164251
ZhangX.WangK.ErvinE.H.2008Bermudagrass freezing tolerance associated with abscisic acid metabolism and dehydrin expression during cold acclimationJ. Amer. Soc. Hort. Sci.133542550
ZhangX.WangK.ErvinE.H.WaltzC.MurphyT.2011Metabolic changes during cold acclimation and deacclimation in five bermudagrass varieties. I. Proline, total amino acid, protein, and dehydrin expressionCrop Sci.51838846