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TURFGRASS SCIENCE

Protein Alterations in Tall Fescue in Response to Drought Stress and Abscisic Acid

Dep. of Plant Science, Rutgers University, New Brunswick, NJ 08901

* Corresponding author (huang{at}aesop.rutgers.edu)

	ABSTRACT

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Drought stress may alter protein synthesis in turfgrasses. The objectives of this study were to investigate physiological changes associated with the synthesis of dehydrin and a cytosolic-heat shock protein (HSC 70) in response to drought stress in two tall fescue (Festuca arundinacea L.) cultivars, ‘Southeast’ and ‘Rebel Jr.’. The effects of abscisic acid (ABA) application on the drought tolerance of the cultivars also were evaluated. The cultivars were subjected to three treatments in growth chambers: well-watered control, drought stress, and drought stress following ABA treatment. Turf quality and leaf relative water content (RWC) decreased and electrolyte leakage (EL) increased during drought stress for both cultivars. The ABA-treated plants maintained higher turf quality and RWC, and lower EL than untreated plants under drought stress conditions. Levels of 20- and 29-kDa polypeptides increased during drought stress, and a 35-kDa polypeptide was noted in both cultivars only when subjected to drought stress either with or without ABA treatment. Immunoblot analysis indicated that dehydrin-like polypeptides of about 23-60 kDa were induced by progressive water deficit in both cultivars. The 53 kDa dehydrin polypeptide was present in Southeast with or without ABA treatment at 10 d of drought stress, whereas the 40 kDa dehydrin polypeptide accumulated in Rebel Jr. in both treatment. The 23- and 27-kDa dehydrin polypeptides were present at 10 d in drought-stressed and ABA-treated plants in both cultivars, but were more pronounced in the drought-stressed plants without ABA. A cytosolic-heat shock protein (HSC 70) was detected in plants in all treatments including well-watered plants of both cultivars, but its levels were higher in drought-stressed and ABA-treated plants. No single dehydrin polypeptide was induced by ABA treatment under drought stress, however, the promotive effects of ABA on the reduced drought stress paralleled the delayed induction of protein synthesis in tall fescue.

Abbreviations: RWC, relative water content • EL, electrolyte leakage • SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis • HS 70, heat shock 70 kDa • HSC 70, heat-shock cognate 70 kDa • PMSF, phenylmethylsulfonyl fluoride • LSD, least significance difference

	INTRODUCTION

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NUMEROUS PHYSIOLOGICAL and biochemical changes occur in response to drought stress in various plant species. The alteration of protein synthesis or degradation is one of the fundamental metabolic processes that may influence drought tolerance (Chandler and Robertson, 1994; Ouvrard et al., 1996). Both quantitative and qualitative changes of proteins were detected during water stress (Riccardi et al., 1998). Evidence is increasing in favor of a relationship between the accumulation of drought-induced proteins and physiological adaptations to water limitation (Bray, 1993; Han and Kermode, 1996; Riccardi et al., 1998).

The dehydrin family of proteins accumulates in a wide range of plant species under dehydration stress [late embryogenesis abundant (LEA) D11 family], which range in size from 9 to 200 kDa (Close, 1996). Dehydrins are hydrophilic, and heat stable and may protect other proteins and help maintain the physiological integrity of cells (Bray, 1993; Close et al., 1993). Arora et al. (1998) reported that the accumulation of dehydrin proteins (25-60 kDa) in zonal geranium (Pelargonium hortorum, cv. Evening glow) leaves induced by water stress was associated with increased heat tolerance. Drought regulation of dehydrin gene expression was observed in both drought-tolerant and drought-susceptible cultivars (Cellier et al., 1998; Wood and Goldsbrough, 1997).

Dehydrin synthesis in response to abscisic acid (ABA) also has been observed (Cellier et al., 1998; Giordani et al., 1999). A correlation occurred between dehydrin gene transcript level and endogenous ABA content in maize (Zea mays L.) (Mao et al., 1995). Exogenous application of ABA to several plant species induced a number of dehydrin-like proteins during dehydration or when under drought stress (Bradford and Chandler, 1992; Han and Kermode, 1996; Pelah et al., 1997). The pathways of expression of dehydrins were found to be ABA-independent or only dehydration-dependent (Espelund et al., 1995; Whitsitt et al., 1997).

The HS 70 family of heat-shock proteins also are a class of stress related proteins (Vierling, 1991). The family of Hs70 is an evolutionarily conserved family of 70-kDa proteins, which are considered to function as molecular chaperones (Anderson et al., 1994; Ellis and Van der Vies, 1991) and are presumed to play a role in protein folding and transport (Giorini and Galili, 1991). Heat shock cognates, such as cytosolic HSC 70, are constitutive and not induced strongly by heat shock (Lindquist and Craig, 1988). They also accumulate during water stress (Arora et al., 1998).

Although the alterations of proteins such as dehydrins under stress conditions have been investigated widely in many plant species, reports on identifying and understanding the role of drought stress-related proteins in cool-season turfgrasses are very limited. For example, little is known about the pattern of changes in the accumulation of dehydrin and HSC 70 under drought stress and the effects of ABA on their expressions in cool-season turfgrasses. Knowledge of protein alterations under drought stress would help identify physiological traits that could be incorporated into breeding programs to improve drought tolerance of cool-season turfgrasses. Therefore, the objectives of this study were to determine changes in soluble protein, dehydrin, and HSC 70 in response to drought stress in two tall fescue cultivars, ‘Southeast’ and ‘Rebel Jr.’, and the possible role of ABA on drought tolerance. Two cultivars were evaluated to examine whether the effects of ABA on drought responses were consistent between cultivars.

	MATERIALS AND METHODS

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Plant Materials and Growth Conditions
Seeds of ‘Southeast’ and ‘Rebel Jr.’ of tall fescue were sown in pots (20 cm in diam and 23 cm deep) containing topsoil (fine, montmorillontic, mesic, Aquic Arquidolls). Soil had pH of 6.5 and contained the following elements (mg g^-1): NH₄-N, 12.5; NH₃-N, 71.6; P, 23; K, 197; Ca, 2477; Mg, 282; Na, 27.6; Cl, 20. In the greenhouse, a starter fertilizer of (9N-13P-7K) (Voluntary Purchasing Groups Inc., Bonham, TX) was applied to provide 49 kg N ha^-1. After germination, plants were fertilized with 500 mL of liquid 20N-10P-20K fertilizer pot^-1 (Scotts-Sierra Horticultural Products Comp. Marysville, OH) on alternate days to provide 64 kg N ha^-1 until drought stress was imposed. Plants were grown in the greenhouse for 60 d and then transferred to growth chambers with a temperature regime of 20°C/15°C (day/night), a 14-h photoperiod, and a photosynthetically active radiation of 400 mmol m^-2 s^-1. Plants were well-watered and maintained as described above for 15 d to allow for adaptation to growth chamber conditions before drought stress was imposed.

Water Stress and ABA Treatments
Water stress was imposed by withholding irrigation for 10 d from plants treated or untreated with ABA. Control plants were well-watered by irrigating every other day without ABA application. For ABA treatment, 40 ml of ABA (100 mM) solution were sprayed uniformly on foliage with a spray bottle at 10:00 h once daily for a 3-d period before drought stress was initiated. Plants untreated with ABA were sprayed with 40 ml of deionized water. The treatments (drought + ABA; drought - ABA; control - ABA) were arranged in a completely randomized design with four replicates.

Measurements of Physiological Parameters
Turf quality was rated visually as an integral of grass color, uniformity, and density on the scale of 0 (desiccated, brown leaves) to 9 (turgid, green leaves) (Turgeon, 1999). The minimum acceptable quality level was 6.

Leaf relative water content (RWC) was determined according to the method of Barrs and Weatherley (1962) and was based on the following calculation: RWC = x 100, where FW is leaf fresh weight, DW is dry weight of leaves after drying at 85°C for 3 d, and SW is the turgid weight of leaves after soaking in water for 4 h at room temperature (approximately 20°C).

Electrolyte leakage (EL) of leaves was measured by the method of Blum and Ebercon (1981) and Marcum (1998) with modifications. Leaves were excised and cut into 2-cm segments. After being rinsed 3 times with distilled deionized H₂O, 10–15 leaf segments were placed in a test tube containing 10 mL distilled deionized H₂O. Test tubes were agitated on a shaker for about 17–18 h, and the solution conductivity (C₁) was measured with a conductivity meter (Model 32, Yellow Springs Instrument Inc., Yellow Springs, OH). Leaf samples then were killed in an autoclave at 121°C for 15 min, and the conductivity of the solution containing killed tissue was measured after tubes cooled down to room temperature (C₂). The relative electrolyte leakage was calculated as (C₁/C₂) x 100.

Protein Extraction
Total soluble protein was extracted from leaves according to the method of Arora et al. (1992) with a few modifications. Leaf tissue (0.5 g fresh weight) was ground with liquid N₂ to a fine powder. Protein was extracted in 2 ml of borate buffer (50 mM sodium borate, 50 mM ascorbic acid, 1% b-mercaptoethanol, 1 mM phenylmethylsulfonyl fluoride, [PMSF], pH 9.0). Samples then were centrifuged at 26000 g at 4°C for 1 h, and supernatant was collected. Protein content was determined by the method of Bradford (1976). Briefly, 100 mL of protein sample was mixed with 5 mL of protein regent (Sigma, St. Louis, MO), and the absorbance was measured at 595 nm after 2 min and before 1 hr using a spectrophotometer (Spectronic instrument Inc., Rochester, NY). Bovine serum albumin was used as a standard (Sigma, St. Louis, MO).

SDS-PAGE and Immunoblots
Samples for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were prepared by the method of Wetzel et al. (1989). The volume of each extract contained an equal amount of protein (200 mg) diluted to 1 ml with deionized water. The diluted protein samples were precipitated by adding 100 ml of trichloroacetic acid (final concentration of about 10%, v/v). The precipitate was collected by centrifugation at 16000 g for 15 min at 4°C, washed with acetone and dried. The pellet then was dissolved in 100 ml of SDS-PAGE sample buffer (65 mM Tris-HCl, 10% glycerol, 2% SDS, pH 6.8, 5% b-mercaptoethanol) (Laemmli, 1970). Proteins were separated by discontinous SDS-PAGE with a PROTEAN II electrophoresis unit (Bio-Rad, La Jolla, CA) using a 4% stacking gel and 12.5% running gel. Gels were stained over night with Colloidal Coomassie Blue G-250 (Neuhoff et al., 1998).

For immunoblotting, SDS unstained gels containing 15 mg protein per sample were electroblotted onto nitrocellulose membrane with 0.45-mm pores (Mini Trans-Blot Electrophoretic Transfer Cell, Bio-Rad, Hercules, CA) for 1.25 h at 100 V in Towbin buffer (Towbin et al., 1979). Gel membranes were blocked with 3% (w/v) nonfat milk in Tris-buffer saline plus Tween 20 (TBST). The membranes were probed overnight with 1:1000 dilution of antidehydrin antiserum (kindly provided by Dr. T.J. Close, Univ. of California, Riverside, CA) or with 1:1000 dilution of antiheat-shock protein (anti-HSC 70) polyclonal antibody (StressGen Biotech. Corp., Victoria, Canada). After three washes in TBST, membranes were incubated with the secondary goat antirabbit IgG (dilution 1:10000) conjugated with alkaline phosphatase for 1 h at room temperature. The bands were detected with a premixed BCIP/NBT substrate solution (Sigma, St. Louis, MO). The SDS-PAGE and immunoblot analyses of protein were repeated three times.

Analysis of variance was based on the general linear model procedure of the Statistics Analysis System (SAS) (SAS Institute Inc., Cary, NC). Effects of drought stress and ABA treatment were analyzed by comparing responses with their respective controls at a given time of treatment. The least significance difference (LSD) at P = 0.05 probability level was used to detect the differences among treatment means.

	RESULTS

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Physiological Responses to Drought Stress
Turf quality rating decreased to below 6 at 10 d of drought stress in both cultivars, but plants treated with ABA maintained higher quality than untreated plants (Table 1). Leaf relative water content (RWC) decreased during drought stress. For Southeast, RWC's of ABA-treated plants were about 28 and 12% higher than those of untreated plants at 5 and 10 d of stress, respectively. For Rebel Jr., ABA-treated plants had 27% and 15% higher RWC's than untreated plants at 5 and 10 d, respectively.

For Southeast, total soluble protein content increased at 10 d in drought-stressed and ABA-treated plants, but ABA-treated plants had a protein content similar to that of untreated plants. For Rebel Jr., protein content decreased in drought-stressed plants at 10 d, and ABA-treated plants had higher protein content than untreated plants (Table 1).

Protein Changes
The SDS-PAGE analysis of soluble protein from leaves revealed that several polypeptides of 20-, 29- and 35-kDa accumulated or their band intensities increased during drought stress in both cultivars (Fig. 1) . Specifically, an accumulation of the 35-kDa polypeptide was noted only in drought-stressed plants with or without ABA treatment for both cultivars. The level of the 29-kDa polypeptide was higher in drought-stressed and ABA-treated plants than in well-watered plants for both cultivars. The 20-kDa polypeptide barely was detected in well-watered plants, but was clearly present in drought-stressed plants with or without ABA treatment for both cultivars. For Southeast, the intensity of 20-kDa polypeptide was higher in ABA-treated plants than untreated plants.

View larger version (60K): [in this window] [in a new window]   Fig. 1. The SDS-PAGE profiles of soluble protein from tall fescue leaves under drought stress for Southeast and Rebel Jr. Molecular weight markers (MW) for lanes: (1) well-watered plants; (2) 5 d of drought stress; (3) 10 d of drought stress; (4) ABA treatment at 5 d of drought; and (5) ABA treatment at 10 d of drought stress, respectively. Equal amounts of protein (30 mg) were loaded in each lane. Arrows indicate protein changes in response to drought and ABA treatment.

View larger version (44K): [in this window] [in a new window]   Fig. 2. Immunoblots of soluble protein from tall fescue leaves under drought stress and probed with dehydrin antibody for Southeast and Rebel Jr. Molecular weight markers (MW) for lanes: (1) well-watered plants; (2) 5 d of drought stress; (3) 10 d of drought stress; (4) ABA treatment at 5 d of drought; and (5) ABA treatment at 10 d of drought stress, respectively. All lanes were loaded with 15 mg protein. Arrows indicate dehydrin-like proteins in response to drought and ABA treatment.

View larger version (39K): [in this window] [in a new window]   Fig. 3. Immunoblots of soluble protein from tall fescue leaves under drought stress and probed with HSC 70 antibody for Southeast and Rebel Jr. Molecular weight markers (MW) for lanes: (1) well-watered plants; (2) 5 d of drought stress; (3) 10 d of drought stress; (4) ABA treatment at 5 d of drought; and (5) ABA treatment at 10 d of drought stress, respectively. All lanes were loaded with 15 mg protein. Arrows indicate HSC 70 in response to drought and ABA treatment.

	DISCUSSION

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Drought-induced polypeptides have been observed in many studies (Arora et al., 1998; Bewley et al., 1983; Perez-Molphe-Balch et al., 1996; Riccardi et al., 1998), and they are assumed to play a role in water stress tolerance. Our results in tall fescue also indicated that accumulation of a 35-kDa polypeptide was responsive to drought stress, and the other two polypeptides of 20 and 29-kDa were intensified in drought-stressed plants for both cultivars. No relationship between protein changes and drought tolerance was apparent in this study, similar to the results reported by Perez-Molphe-Balch et al. (1996). However, ABA-treated plants of Southeast had a higher level of a 20-kDa polypeptide than untreated plants at 10 d of drought stress, suggesting that this protein may play a role in ABA-enhanced drought tolerance. Because ABA-mediated protein changes were found only in one cultivar, the functional role of drought-responsive proteins and the regulation of ABA in tall fescue needs to be investigated further. Pruvot et al. (1996) reported that a drought-induced increase in the synthesis of a chloroplastic protein of 34-kDa likely was regulated by ABA application.

Recently, drought-induced dehydrin proteins have been found in many species (Arora et al., 1998; Han et al., 1997; Pelah et al., 1997; Wechsberg et al., 1994). Drought–induced expressions of dehydrin genes were identified in both drought-tolerant and-sensitive cultivars of sorghum (Sorghum bicolor L.) (Wood and Goldsbrough, 1997) or to a higher level in tolerant cultivars of wheat (Triticum durum L.) (Labhilili et al., 1995) or in sensitive cultivars of cocksfoot (Dactylis glomerata L.) (Volaire et al., 1998). In this study, dehydrin-like proteins with polypeptides ranging from 23 to 60 kDa, especially 23- and 27-kDa, were present, and their intensities increased with progressive water deficit when leaf RWC dropped to about 47% in drought-stressed plants in both tall fescue cultivars. Also, the 53 kDa polypeptide largely accumulated in Southeast and the 40 kDa polypeptide accumulated in Rebel Jr. only at 10 d of drought stress. These results indicated that the accumulation of dehydrin was induced strongly by severe drought stress. Wechsberg et al. (1994) also found that the accumulation of 18-, 28-, 31-kDa dehydrin-like proteins in the seeds of crowfoot (Ranunculus sceleratus L.) depended on stages of water stress. Accumulation of dehydrin protein could protect cells from further dehydration during drought stress (Cellier et al., 1998; Han and Kermode, 1996).

Dehydrins have been found to be induced by ABA in other species (Cellier et al., 1998; Giordani et al., 1999). However, in the present study, no specific dehydrins were induced by an application of 100 mM ABA. Dehydrin polypeptides of 53-kDa and 40-kDa did not occur in ABA-treated plants when leaf RWC was 88–90%, but appeared when leaf RWC dropped to about 60%. Yamaguchi-Shinozaki and Shinozaki (1994) reported that ABA-independent and the ABA-dependent signal transduction pathways might exist between stress and dehydrin gene expression. Giordani et al. (1999) suggested that these two pathways of regulating dehydrin transcript accumulation might have cumulative effects. Our results suggested that the enhancement of drought tolerance by ABA application, as manifested by higher turf quality during drought stress, was not related to the induction of dehydrins in tall fescue. The ABA-treated plants maintained higher RWC and lower EL. Hence, other mechanisms could be involved in this positive effect of ABA, including the regulation of stomatal closure for water conservation (Davis, 1978), and membrane integrity (Rajasekaran and Blake, 1999).

The HSC 70 protein can accumulate under water stress (Arora et al., 1998) and cold acclimation (Wisniewski et al., 1996). Our results from immunoblots indicated that HSC 70 was not inducible under drought stress, because it also accumulated in well-watered plants. The level of HSC 70, however, was higher in drought-stressed plants than well-watered plants. Arora et al. (1998) found that HSC 70 could be detected only in water-stressed plants. Therefore, the accumulation of HSC 70 under drought stress may vary among plant species.

In summary, drought stress induced changes in protein synthesis in tall fescue. Accumulations of dehydrins were detected in drought-stressed and ABA-treated plants of both cultivars, which could protect plants from further dehydration damage. The promotive effects of ABA on the enhancement of physiological activities under drought stress paralleled the delayed induction of protein synthesis in tall fescue. However, increased drought tolerance resulting from ABA application might not be directly related to the accumulation of a higher level of dehydrins or a unique dehydrin protein. The two tall fescue ultivars did not differ in their responses to ABA.

Received for publication February 12, 2001.

	REFERENCES

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 

• Anderson, J.V., Q. Li, D.W. Haskell, and C.L. Guy. 1994. Structural organization of spinach endoplasmic reticulum-70-kilodalton heat-shock cognate gene and expression of 70-kilodalton heat-shock genes during cold acclimation. Plant Physiol. 104:1359–1370.[Abstract]
• Arora, R., D.S. Pitchay, and B.C. Bearce. 1998. Water-stress-induced heat tolerance in geranium leaf tissues: A possible linkage through stress proteins? Physiol. Plant. 103:24–34.
• Arora, R., M.E. Wisniewski, and R. Scorza. 1992. Cold acclimation in genetically related (sibling) deciduous and evergreen peach [Prunus persica (L.) Batsch]. I. Seasonal changes in cold hardiness and polypeptides of bark and xylem tissues. Plant Physiol. 99:1562–1568.[Abstract/Free Full Text]
• Barrs, H.D., and P.E. Weatherley. 1962. A re-examination of the relative turgidity techniques for estimating water deficits in leaves. Aust. J. Biol. Sci. 15:413–428.
• Bewley, J.D., K.M. Larsen, and J.E.T. Papp. 1983. Water-stress-induced changes in the pattern of protein synthesis in maize seedling mesocotyls: A comparison with the effects of heat shock. J. Exp. Bot. 34:1126–1133.[Abstract/Free Full Text]
• Blum, A., and A. Ebercon. 1981. Cell membrane stability as measurement of drought and heat tolerance in wheat. Crop Sci. 21:43–47.
• Bradford, M.M. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 72:248–254.[Web of Science][Medline]
• Bradford, K.J., and P.M. Chandler. 1992. Expression of dehydrin-like proteins in embryos and seedlings of Zizania palustris and Oryza sativa during dehydration. Plant Physiol. 99:488–494.[Abstract/Free Full Text]
• Bray, E.A. 1993. Molecular responses to water deficit. Plant Physiol. 103:1035–1040.[Web of Science][Medline]
• Cellier, F., G. Conejero, J.C. Breitler, and F. Casse. 1998. Molecular and physiological responses to water deficit in drought-tolerant and drought-sensitive lines of sunflowers. Accumulation of dehydrin transcripts correlates with tolerance. Plant Physiol. 116:319–328.[Abstract/Free Full Text]
• Chandler, P.M., and M. Robertson. 1994. Gene expression regulated by abscisic acid and its relation to stress tolerance. Annu. Rev. Plant Physiol. Plant Mol. Biol. 45:113–141.[Web of Science]
• Close, T.J. 1996. Dehydrins: Emergence of a biochemical role of a family of plant dehydration proteins. Physiol. Plant. 97:795–803.
• Close, T.J., R.D. Fenton, A. Yang, R. Asghar, D.A. DeMason, D.E. Crone, N.C. Meyer, and F. Moonan. 1993. Dehydrin: The protein. p. 104–114. In T.J. Close and E.A. Bray (ed.) Plant responses to cellular dehydrin during environmental stress. American Society of Plant Physiologists, Rockville, MD.
• Davis, W.J. 1978. Some effects of abscisic acid and water stress on stomata of Vicia faba. J. Exp. Bot. 29:175–182.[Abstract/Free Full Text]
• Ellis, R.J., and S.M. Van der Vies. 1991. Molecular chaperones. Annu. Rev. Biochem. 60:321–347.[Web of Science][Medline]
• Espelund, M., J.A. de Bedout, W.H. Outlaw Jr., and K.S. Jakobsen. 1995. Environmental and hormonal regulation of barley late-embryo-genesis-abundant (Lea) mRNA is via different signal transduction pathways. Plant Cell Environ. 18:943–949.
• Giordani, T., L. Natali, D.A. Ercole, C. Pugliesi, M. Fambrini, P. Vernieri, C. Vitagliano, and A. Cavallini. 1999. Expression of a dehydrin gene during embryo development and drought stress in ABA-deficient mutants of sunflower (Helianthus annuus L.) Plant Mol. Biol. 39:739–748.
• Giorini, S., and G. Galili. 1991. Characterization of HSP-70 cognate proteins from wheat. Theor. Appl. Genet. 82:615–620.
• Han, B., P. Berjak, N. Pammenter, J. Farrant, and A.R. Kermode. 1997. The recalcitrant plant species, Castanospermum australe and Trichilia dregeana, differ in their ability to produce dehydrin-related polypeptides during seed maturation and in response to ABA or water-deficit-related stresses. J. Exp. Bot. 48:1717–1726.
• Han, B., and A.R. Kermode. 1996. Dehydrin-like proteins in castor bean seeds and seedlings are differentially produced in responses to ABA and water-deficit-related stresses. J. Exp. Bot. 47:933–939.
• Labhilili, M., P. Joudrier, and M.F. Gautier. 1995. Characterization of cDNAs encoding Triticum durum dehydrins and their expression patterns in cultivars that differ in drought tolerance. Plant Sci. 112:219–230.
• Laemmli, U.K. 1970. Cleavage of structure proteins during the assembly of the head of bacteriophage T4. Nature 227:680–685.[Medline]
• Lindquist, S.C., and E.A. Craig. 1988. The heat-shock-proteins. Annu. Rev. Genet. 22:631–677.[Web of Science][Medline]
• Mao, Z., R. Paiva, and A.L. Kriz. 1995. Dehydrin gene expression in normal and viviparous embryos of Zea mays during seed development and germination. Plant Physiol. Biochem. 33:649–653.
• Marcum, K.B. 1998. Cell membrane theromostability and whole-plant heat tolerance of Kentucky bluegrass. Crop Sci. 38:1214–1218.[Abstract/Free Full Text]
• Neuhoff, V., A.D. Taube, and W. Eirhardt. 1988. Improved staining of proteins in polyacrylamide gels including isoelectric focusing gels with clear background at nanogram sensitivity using Coomassie Brilliant Blue G-250 and R-250. Electrophoresis 9:255–262.[Web of Science][Medline]
• Ouvrard, O., F. Cellier, K. Ferrare, D. Tousch, T. Lamaze, J.M. Dupuis, and F. Casse-Delbart. 1996. Identification and expression of water stress- and abscisic acid-regulated genes in a drought-tolerant sunflower genotype. Plant Mol. Biol. 31:819–829.[Web of Science][Medline]
• Pelah, D., O. Shoseyov, A. Altman, and D. Bartels. 1997. Water-stress responses in aspen (Populus tremula): Different accumulations of dehydrin, sucrose synthase, GAPDH homologues, and soluble sugars. J. Plant Physiol. 151:96–100.
• Perez-Molphe-Balch, E., M. Gidekel, M. Segura-Nieto, L. Herrera-Estrella, and N. Ochoa-Alejo. 1996. Effects of water stress on plant growth and root proteins in three cultivars of rice (Oryza sativa) with different level of drought tolerance. Physiol. Plant. 96:284–290.
• Pruvot, G., J. Massimino, G. Peltier, and P. Rey. 1996. Effects of low temperature, high salinity and exogenous ABA on the synthesis of two chloroplastic drought-induced proteins in Solanum tuberosum. Physiol. Plant. 97:123–131.
• Rajasekaran, L.R., and T.J. Blake. 1999. New plant growth regulators protect photosynthesis and enhance growth under drought of jack pine seedlings. J. Plant Growth Reg. 18:175–181.[Medline]
• Riccardi, F., P. Gazeau, D.V. Vienne, and M. Zivy. 1998. Protein changes in responses to progressive water deficit in maize. Plant Physiol. 117:1253–1263.[Abstract/Free Full Text]
• Sheffer K.M., J.H. Dunn, and D.D. Minner. 1987. Summer drought responses and rooting depth of three cool-season turfgrasses. HortScience 22:296–297.
• Turgeon, A.J. 1999. Turfgrass management. Prentice Hall, Englewood Cliffs, NJ.
• Vierling, E. 1991. The roles of heat-shock-proteins in plants. Annu. Rev. Plant Physiol. Plant Mol. Biol. 42:579–620.[Web of Science]
• Volaire, F., H. Thomas, N. Bertagne, E. Bourgeois, M.F. Gautier, and F. Lelievre. 1998. Survival and recovery of perennial forage grasses under prolonged Mediterranean drought: Water status, solute accumulation, abscisic acid concentration and accumulation of dehydrin transcripts in bases of immature leaves. New Phytol. 140: 451–460.
• Wechsberg, G.E., C.M. Bray, and R.J. Probert. 1994. Expression of dehydrin-like protein in orthodox seeds of Ranunculus scleratus during development and water stress. Seed Sci. Res. 4:241–246.
• Wetzel, S., C. Demmers, and J.S. Greenwood. 1989. Seasonally fluctuating bark proteins are a potential form of nitrogen storage in three temperate hardwoods. Planta 178:275–281.[Web of Science]
• Whitsitt, M.S., R.G. Collis, and J.E. Mullet. 1997. Modulation of dehydration tolerance in soybean seedlings. Dehydrin Mat1 is induced by dehydration but not by abscisic acid. Plant Physiol. 114: 917–925.[Abstract]
• Wisniewski, M., T.J. Close, T. Artlip, and R. Arora. 1996. Seasonal patterns of dehydrins and 70-kDa heat-shock proteins in bark tissue of eight species of woody plants. Physiol. Plant 96:496–505.
• Wood, A.J., and P.B. Goldsbrough. 1997. Characterization and expression of dehydrins in water-stressed Sorghum bicolor. Physiol. Plant 99:144–152.
• Yamaguchi-Shinozaki, K., and K. Shinozaki. 1994. A novel cis-acting element in an Arabidopsis gene is involved in responsiveness to drought, low temperature, or high salt stress. Plant Cell 6:251–264.[Abstract]

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				Y. Zhang, M. A. R. Mian, and J. H. Bouton Recent Molecular and Genomic Studies on Stress Tolerance of Forage and Turf Grasses Crop Sci., February 1, 2006; 46(2): 497 - 511. [Abstract] [Full Text] [PDF]

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