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TURFGRASS SCIENCE

Growth and Physiological Responses of Creeping Bentgrass to Changes in Air and Soil Temperatures

Dep. of Horticulture, Forestry, and Recreation Resources, Kansas State Univ., Manhattan, KS 66506-5506 USA

bhuang{at}oz.oznet.ksu.edu

	ABSTRACT

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High air or soil temperature is a major factor limiting growth of cool-season grasses during summer months in the transition zone and warm climate regions. Knowledge of how cool-season grasses respond to differential high air and soil temperatures would facilitate our understanding of heat tolerance mechanisms. The objectives of this study were to compare the influence of air versus soil temperature on turf quality, physiological activities, and root growth of creeping bentgrass (Agrostis palustris Huds. cv. Penncross), and to investigate whether shoot and root growth could be improved by reducing soil temperature at high air temperatures. Shoots and roots were exposed to four air/soil temperature regimes (20/20, 20/35, 35/20, and 35/35°C) for 56 d in growth chambers. High soil (20/35°C) and high air/soil (35/35°C) temperatures reduced canopy photosynthetic rate (P_n), turf quality, and the number of roots. High air/soil temperatures also reduced photochemical efficiency (Fv/Fm). The adverse effects of high air/soil temperatures were more pronounced than either high soil or air temperature alone for turf quality, Fv/Fm, P_n, and root growth. High soil temperature was more detrimental than high air temperature. Lowering soil temperature at high air temperatures (35/20°C) increased root growth, canopy P_n, Fv/Fm, and turf quality, compared with high soil temperature at low or high air temperatures (20/35 and 35/35°C). The results demonstrated that roots mediated shoot responses to high temperature stress in creeping bentgrass, and that reducing root-zone temperature could help maintain quality creeping bentgrass under supraoptimal ambient temperatures.

Abbreviations: Fv/Fm, photochemical efficiency • LSD, least significance difference • P_n, canopy photosynthetic rate

	INTRODUCTION

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TURF QUALITY of creeping bentgrass often declines during summer when golf greens receive maximum use in transitional and warm climate regions (Lucas, 1995; Carrow, 1996). The optimum temperatures for cool-season grass range from 15 to 24°C for shoot growth and 10 to 18°C for root growth (Beard, 1973). However, air temperature in the transitional and warm climate regions often approaches 30°C or higher, and soil temperatures also often reach levels well above the optimum for root growth. High air and/or soil temperatures may be the primary stresses leading to summer bentgrass decline (Carrow, 1996).

The lower optimum temperature for root growth than for shoot growth of cool-season grasses indicates that roots may be more sensitive to high temperatures. (Beard, 1973). Root growth of Kentucky bluegrass (Poa pratensis L.) was inhibited as soil temperature increased to 25°C (Aldous and Kaufmann, 1979). Root growth and initiation in creeping bentgrass stopped when soil temperature was above 25°C (Lucas, 1995; Beard and Sifers, 1997; Huang et al., 1998). Soil temperature strongly influenced shoot growth of winter wheat (Triticum aestivum L.) by regulation of cytokinin production in roots (Kuroyanagi and Paulsen, 1988). Direct injury to roots by high soil temperatures could well be the initial factor in high temperature responses of plants.

Reducing soil temperature by any means may alleviate or prevent the summer bentgrass decline problem. Reducing root-zone temperature has been shown to increase root growth, export of cytokinin from roots, leaf photosynthesis, chlorophyll content, protein synthesis, and shoot growth in several plant species (Skene and Kerridge, 1967; Feierabend and Mikus, 1977; Aldous and Kaufmann, 1979; Martin et al., 1985; Kuroyanagi and Paulsen, 1988; Graves et al., 1991; Clarck and Reinhard, 1991; Udomprasert et al., 1995; Ziska, 1998). However, whether shoot and root growth of creeping bentgrass can be improved by reducing root-zone temperature when shoots are exposed to supraoptimal air temperatures, has not been studied. Furthermore, the relative effects of air compared with soil temperatures on creeping bentgrass are not well understood.

The objectives of this study were (i) to compare the influences of air versus soil temperature on turf quality, physiological activities, and root growth and (ii) to investigate whether growth and turf quality of creeping bentgrass could be improved by reducing soil temperature under high ambient temperature conditions.

	Materials and methods

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Sods of creeping bentgrass (cv. Penncross) were collected from the Rocky Ford Turfgrass Research Center, Manhattan, KS, and transplanted in a mixture (9:1, v/v) of sand and fritted clay (Profile, AILMOR, Deerfield, IL) in clear polyethylene bags (5 cm in diameter and 40 cm in length, with holes drilled at the bottom for drainage). The polyethylene bags were placed in polyvinylchloride (PVC) tubes of the same diameter and length. The PVC tubes were installed vertically in water baths, with the open end exposed outside of the water bath for drainage. These were designed in a way that enabled plant growth in well-drained soil in polyethylene bags, while soil temperature was controlled at a constant, predetermined level. Plants were grown in growth chambers at 20/15°C (day/night), 400 µmol m^-2 s^-1 photosynthetic photon flux density and a 13-h photoperiod for 40 d before differential shoot/root temperature treatments were imposed. Before and during temperature treatments, turf was mowed daily at 3 to 4 mm height with electric hair clippers, watered daily until soil moisture reached field capacity (when free drainage ceased from the bottom of the plant containers), and fertilized weekly with 100 mL full-strength Hoagland's nutrient solution (Hoagland and Arnon, 1950).

Shoots and roots were exposed to four air/soil temperature regimes: 20/20, 20/35, 35/20, and 35/35°C for 56 days. These test temperatures were chosen because 20°C is within the optimum temperature range for the growth of cool-season grasses, and 35°C commonly occurs in the transitional and warm climatic regions during mid-summer. Shoots were maintained at the ambient temperature (20 or 35°C) of the growth chambers, which was regulated by a temperature controller. Soil temperature was controlled by maintaining the entire root zone (40-cm-long soil column in a polyethylene bag) in water baths with predetermined temperatures (20 or 35°C). The low temperature was controlled with circulating cool water (18–20°C), and the high temperature with an immersion circulating heater (IC-2100, Fisher Scientific Inc., Pittsburgh, PA). Water was circulated continuously to maintain constant and uniform temperatures. Water levels were maintained at the top edges of both water baths during the experimental period.

Air temperatures at various distances from the canopy and soil temperatures at different depths from the soil surface were measured biweekly with thermocouples connected to a thermometer (Fig. 1) . In the 20/20°C treatment, both air and soil were maintained around 20°C; in the 20/35°C treatment, air temperature ranged from 23 to 25°C, and root-zone temperature was approximately 35°C; in the 35/20°C treatment, air temperature ranged from 32 to 35°C, while root-zone temperature ranged from 18 to 21°C; and in the 35/35°C treatment, air and root-zone temperatures were maintained at 33 to 36°C.

View larger version (21K): [in this window] [in a new window]   Fig. 1 Temperature profiles in soil and air under four differential air/soil temperature regimes. Data points represent an average (± standard error) of four replicates. Standard errors that are not shown are small and covered by the symbols

Turf quality was visually rated weekly after treatments were initiated, and was based on color, density, and uniformity on a 0 (worst, all plant were dead and brown) to 9 scale (best, all plants were healthy and green), with scales above 6 being acceptable quality. Leaf photochemical efficiency was expressed as leaf chlorophyll fluorescence (Fv/Fm). The Fv/Fm ratio of leaves was determined with a chlorophyll fluorescence meter (Dynamax, Houston, TX) by pressing the light source chamber to leaves that were adapted in dark for 20 min.

Diurnal gas exchange rate was measured every 2 h from 0900 to 1300 h on 28 d of treatment with a LI-6400 portable gas exchange system (LI-COR Inc., Lincoln, NE). Turf canopy was enclosed in a transparent plexiglass chamber fitted to the CO₂ analyzer in LI-6400. Canopy net photosynthetic rate (Pn) was expressed as CO₂ uptake per unit turf canopy area (m^-2). Changes in canopy photosynthetic rate (P_n) with duration of treatment was also determined by measuring P_n from 10:00 to 14:00 h weekly using the LI-6400 gas exchange system.

The number of roots at different soil depths was determined nondestructively with an imaging system. Roots visible on the side wall of the transparent polyethylene bags were recorded at depths of 0 to 2, 5 to 7, 15 to 17, 25 to 27, and 35 to 25 cm from the soil surface using a video-camera recorder (Sony, CCD-TRV70, Japan). The number of roots within a 2- by 3-cm area at each soil depth was determined from the root images.

Plants from four tubes in each treatment were harvested biweekly to determine root fresh weight. Fresh weight was determined after roots were washed and blotted dry with paper towels.

	Results

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Turf Quality
Creeping bentgrass grown at 20/20°C maintained the highest turf quality among the four temperature treatments during the experiment (Fig. 2) . Turf quality at 35/20°C was not different from that at 20/20°C throughout 49 d of treatment, but was higher than that at 20/35°C and 35/35°C from 14 to 54 d of treatment.

View larger version (20K): [in this window] [in a new window]   Fig. 2 Turf quality responses to differential air/soil temperatures. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment. Vertical bars on the right indicate LSD for comparisons of changes over treatment duration within a treatment

Canopy Photosynthetic Rate
Canopy photosynthetic rate (P_n) for grasses grown at 20/20°C and 35/20°C remained relatively constant during the experimental period (Fig. 3) . However, P_n declined to below the control level within 8 d after roots (20/35°C) and 1 d after both shoots and roots (35/35°C) were exposed to high temperature and continued to decline with treatment duration. The decline in P_n was more severe at 35/35°C than at 20/35°C. The P_n at 35/20°C was higher than that at 20/35°C and 35/35°C, but was not different from that at 20/20°C during the experiment.

View larger version (23K): [in this window] [in a new window]   Fig. 3 Canopy photosynthetic rate responses to differential air/soil temperatures. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment. Vertical bars on the right indicate LSD for comparisons of changes over treatment duration within a treatment

View larger version (26K): [in this window] [in a new window]   Fig. 4 Diurnal changes of canopy photosynthetic rate under four differential air/soil temperature regimes. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment. Vertical bars on the right indicate LSD for comparisons of changes over time within a treatment

View larger version (19K): [in this window] [in a new window]   Fig. 5 Canopy photochemical efficiency (Fv/Fm) responses to differential air/soil temperatures. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment. Vertical bars on the right indicate LSD for comparisons of changes over treatment within a treatment

Root Fresh Weight
Root fresh weight declined with duration of treatment at 20/35, 35/20, and 35/35°C. This decline was more dramatic at 20/35 and 35/35°C than at 35/20°C (Fig. 6) .

View larger version (20K): [in this window] [in a new window]   Fig. 6 Root fresh weight responses to differential air/soil temperatures. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment. Vertical bars on the right indicate LSD for comparisons of changes over treatment duration within a treatment

Root Number
The number of roots decreased with soil depths in each treatment (Fig. 7) . The numbers of roots remained constant during the experimental period in all soil depths at 20/20°C, in soil depths below 5 cm at 35/20°C, and at depths below 35 cm at 20/35°C (Fig. 7). Significant declines in the root number with treatment duration occurred in the 0- to 2-cm depth at 20/35, 35/20, and 35/35°C; in 5- to 7-, 15- to 17-, and 25- to 27-cm depths at 20/35 and 35/35°C; and in all soil depths at 35/35°C. However, the magnitude of the decline in root number was greater in the surface 7 cm soil than in the deeper soil layers. The decrease in the number of roots in the 0- to 2-cm depth at 35/35°C was more dramatic than decrease in all other treatments. The declines in the number of roots in soil depths below 5 cm were greater at 20/35 and 35/35°C than at 35/20 and 20/20°C.

View larger version (23K): [in this window] [in a new window]   Fig. 7 Relative root number at different soil depths in response to differential air/soil temperatures. Vertical bars on the top indicate LSD for treatment comparisons at a given day of treatment for a given soil depth. Vertical bars on the right indicate LSD for comparisons of changes over treatment duration within a treatment

	Discussions

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The adverse effects of high soil temperature on shoot growth and physiological activities probably are due to direct inhibition of root growth and activity and, therefore, limitation of water and nutrient supplies to the shoot (Kramer, 1983), and disruption of cytokinins synthesis in roots (Itai et al., 1973; Al-Khatib and Paulsen, 1984; Kuroyanagi and Paulsen, 1988; Smart et al., 1991). High soil temperature also promoted leaf senescence by increasing transport of root abscisic acid (ABA) to the shoots (Udomprasert et al., 1995).

High soil temperature or high air and soil temperatures reduced fresh weight and number of roots in different soil depths and accelerated the decline in root weight and number. The decline in the number of roots was more pronounced in the surface 7 cm of soil where most roots were found. Rapid decline in the number of roots under high soil temperatures suggested that root death rate exceeded the rate of new root production, especially in the surface soil layers. Beard and Daniel (1965) reported that no new root growth of creeping bentgrass occurred in the summer, except during two low temperature periods. Aldous and Kaufmann (1979) reported that death of the roots under heat stress initiated the decline of shoot growth in Kentucky bluegrass, which might result from a high temperature-labile process in the roots.

Limited new root production and accelerated root death under high root temperatures may interrupt synthesis and transport of root-produced hormones. Cytokinin is a shoot growth regulator that is synthesized mainly in roots (Skene and Kerridge, 1967). Its synthesis in roots and translocation from roots to shoots have been reported to be inhibited by high soil temperatures. Itai et al. (1973) and Skene and Kerridge (1967) reported adverse effects of high soil temperature on the exudation of cytokinins from detached roots. Heat stress damages to shoot chloroplast activities and ultrastructure are reversed by cytokinin (Caers et al., 1985). Udomprasert et al. (1995) reported that high soil temperature decreased endogenous ABA levels in roots of beans (Phaseolus vulgaris L.), but increased ABA in leaves, possibly by higher transport of root ABA to the shoots, which can cause leaf senescence.

Reducing soil temperature while shoots were exposed to high air temperature increased photosynthetic rate, photochemical efficiency, turf quality, and root growth, relative to plants grown at high soil temperatures. The effect on root growth was indicated by the slow decline or unchanged root fresh weight and the number of roots in different soil depths during high temperature stress to shoots. The increased growth and activity from reducing root temperature could improve the ability of roots to supply water (Kramer, 1983), nutrients (Engels, 1993), and hormones (Skene and Kerridge, 1967) for shoot growth.

Enhancement of shoot growth and physiological activities by reducing soil temperature have been reported in several other species (Aldous and Kaufmann, 1979; Martin et al., 1985; Kuroyanagi and Paulsen, 1988; Ruter and Ingram, 1990; Graves et al., 1991; Udomprasert et al., 1995; Ziska, 1998). Kuroyanagi and Paulsen (1988) reported that cooling roots of winter wheat to 25°C when shoots were exposed to 35°C was nearly as beneficial as growing both roots and shoots at 25°C. Shoot growth rate, specific leaf weight, leaf carbon exchange rate, and stomatal conductance in several plants were enhanced by low soil temperature regardless of the air temperature (Martin et al., 1985; Ziska, 1998). Survival of Kentucky bluegrass was enhanced by controlling soil temperature at 22°C (Aldous and Kaufmann, 1979). Low soil temperature also improved shoot extension in two woody species (Martin et al., 1985).

In summary, this study, along with others, demonstrated that roots had more influence than shoots on whole-plant responses to heat stress. Lowering soil temperature even when air temperature was supraoptimal enhanced growth and physiological activities of shoots and roots. Therefore, any means that reduce soil temperature during hot summers could improve turf quality of creeping bentgrass. The mechanisms for the mediation of high-temperature injury by roots in cool-season turfgrasses deserve investigation.

	ACKNOWLEDGMENTS

 
The authors thank Dr. J.D. Fry for critical reviewing of the manuscript. Funds for this research were provided by the United States Golf Association and Kansas Turfgrass Foundation. Contribution No. 00-62-J from the Kansas Agric. Exp. Stn.

Received for publication September 23, 1999.

	REFERENCES

TOP ABSTRACT INTRODUCTION Materials and methods Results Discussions REFERENCES

 

• Aldous D.E., Kaufmann J.E. Role of root temperature on shoot growth of two Kentucky bluegrass cultivars. Agron. J. 1979;71:545-547.[Abstract/Free Full Text]
• Al-Khatib K., Paulsen G.M. High-temperature effects on photosynthetic processes in temperate and tropical cereals. Crop Sci. 1984;39:119-125.[Abstract/Free Full Text]
• Beard J.B. Turfgrass: Science and culture. Englewood Cliffs, NJ: Prentice-Hall, 1973.
• Beard J.B., Daniel W.H. Effect of temperature and cutting on the growth of creeping bentgrass (Agrostis palustris Huds.) roots. Agron. J. 1965;57:249-250.[Abstract/Free Full Text]
• Beard J.B., Sifers S.I. Bentgrass for putting greens. Golf Course Manag. 1997;65:54-60.
• Caers M., Rudelsheim P., Onckelen H., Horemans S. Effect of heat stress on photosynthetic activity and chloroplast ultrastructure in correlation with endogenous cytokinin concentration in maize seedlings. Plant Cell Physiol. 1985;26:47-52.[Abstract/Free Full Text]
• Carrow R.N. Summer decline of bentgrass greens. Golf Course Manag. 1996;64:51-56.
• Clarck R.B., Reinhard N. Effects of soil temperature on root and shoot growth traits and iron deficiency chlorosis in sorghum genotypes grown on a low iron calcareous soil. Plant Soil 1991;130:97-103.
• Engels C. Differences between maize and wheat in growth-related nutrient demand and uptake of potassium and phosphorus at suboptimal root zone temperatures. Plant Soil 1993;150:129-138.
• Feierabend J., Mikus M. Occurrence of a high temperature sensitivity of chloroplast ribosome formation in several higher plants. Plant Physiol. 1977;59:863-867.[Abstract/Free Full Text]
• Graves W.R., Joly R.J., Dana M.N. Water use and growth of honey locust and tree-of-heaven at high root-zone temperature. HortScience 1991;26:1309-1312.[Abstract/Free Full Text]
• Hoagland, D.R., and D.I. Arnon. 1950. The water-culture method for growing plants without soil. Circular 347. California Agric. Exp. Stn.
• Huang B., Liu X., Fry J.D. Effects of high temperature and poor soil aeration on root growth and viability of creeping bentgrass. Crop Sci. 1998;38:1618-1622.[Abstract/Free Full Text]
• Itai C., Ben-Zioni C.I., Ordin L. Correlative changes in endogenous hormone levels and shoot growth induced by short heat treatments to the root. Physiol. Plant 1973;29:355-360.
• Kempthorne O. The design and analysis of experiments. New York: John Wiley and Sons, 1952.
• Kramer P.J. Water stress research: progress and problems. Current topics in plant biochemistry and physiology. Univ. Missouri-Columbia. 1983;2:129-144.
• Kuroyanagi T., Paulsen G.M. Mediation of high-temperature injury by roots and shoots during reproductive growth of wheat. Plant Cell Environ. 1988;11:517-523.
• Lucas, L.T. 1995. Bentgrass summer decline. North Carolina Turfgrass Summary. 32–33.
• Martin C.A., Ingram D.L., Nell T.A. Supraoptimal root-zone temperature alters growth and photosynthesis of holly and elm. J. Arboriculture 1985;15:272-276.
• Nielsen K.F. Roots and root temperatures. In: Carson E.W., ed. The plant root and its environment. Charlottesville, VA: Univ. Press Virginia, 1974:293-333.
• Ruter J.M., Ingram D.L. ¹⁴Carbon-labeled photosynthate partitioning in Ilex crenata `Rotundifolia' at supraoptimal root-zone temperatures. J. Am. Soc. Sci. 1990;115:1008-1013.
• Skene K.G.M., Kerridge G.H. Effect of root temperature on cytokinin activity in root exudate of Vitis vinifera L. Plant Physiol. 1967;42:1131-1139.[Abstract/Free Full Text]
• Smart C.M., Scofield S.R., Bevan M.W., Dyer T.A. Delayed leaf senescence in tobacco plants transformed with tmr, a gene for cytokinin production in Agrobacterium. Plant Cell 1991;7:647-656.
• Udomprasert N., Li P.H., Davis D.V., Markhart A.H., III. Effects of root temperatures on leaf gas exchange and growth at high air temperature in Phaseolus acutifolius and Phaseolus vulgaris. Crop Sci. 1995;35:490-495.[Abstract/Free Full Text]
• Ziska L.H. The influence of root zone temperature on photosynthetic acclimation to elevated carbon dioxidase concentrations. Ann. Bot. (London) 1998;81:717-721.[Abstract/Free Full Text]

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This Article Abstract Figures Only Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (33) Citing Articles via Google Scholar Google Scholar Articles by Xu, Q. Articles by Huang, B. Search for Related Content PubMed Articles by Xu, Q. Articles by Huang, B. Agricola Articles by Xu, Q. Articles by Huang, B.