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Switchgrass (Panicum virgatum L.) Intraspecific Variation and Thermotolerance Classification Using in Vitro Seed Germination Assay

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DOI: 10.4236/ajps.2011.22015    5,608 Downloads   11,006 Views   Citations


Cardinal temperatures for plant processes have been used for thermotolerance screening of geNotypes, geoclimatic adaptability determination and pheNological prediction. Current simulation models for switchgrass (Panicum virga-tum L.) utilize single cardinal temperatures across geNotypes for both vegetative and reproductive processes although intra-specific variation exists among geNotypes. An experiment was conducted to estimate the cardinal temperatures for seed germination of 14 diverse switchgrass geNotypes and to classify geNotypes for temperature tolerance. Strati-fied seeds of each geNotype were germinated at eight constant temperatures from 10oC to 45oC under a constant light intensity of 35 µmol m-2 s-1 for 12 h d-1. Germination was recorded at 6-h intervals in all treatments. Maximum seed germination (MSG) and germination rate (GR), estimated by fitting Sigmoidal function to germination-time series data, varied among geNotypes. Quadratic and bilinear models best described the MSG and GR responses to temperature, respectively. The mean cardinal temperatures, Tmin, Topt and Tmax, were 8.1, 26.6, and 45.1oC for MSG and 11.1, 33.1, and 46.0oC for GR, respectively. Cardinal temperatures for MSG and GR; however, varied significantly among geNotypes. GeNotypes were classified as sensitive (‘Cave-in-rock’, ‘Dacotah’, ‘Expresso’, ‘Forestburg’, ‘Kanlow’, ‘Sunburst’, ‘Trailblazer’, and ‘Warrior’), intermediate (‘Alamo’, ‘Blackwell’, ‘Carthage’, ‘Shawnee’, and ‘Shelter’) and tolerant (‘Summer’) to high temperature based on cumulative temperature response index (CTRI) estimated by summing individual response indices estimated from the MSG and GR cardinal temperatures. Similarly, geNotypes were also classified as sensitive (Alamo, Blackwell, Carthage, Dacotah, Shawnee, Shelter, and Summer), moderately sensitive (Cave-in-rock, Forestburg, Kanlow, Sunburst, and Warrior), moderately tolerant (Trailblazer), and tolerant (Expresso) to low temperatures. The cardinal temperature estimates would be useful to improve switchgrass models for field applications. Additionally, the identified cold- and heat-tolerant geNotypes can be selected for niche environments and in switchgrass breeding programs to develop new geNotypes for low and high temperature environments.

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The authors declare no conflicts of interest.

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R. Seepaul, B. Macoon, K. Reddy and B. Baldwin, "Switchgrass (Panicum virgatum L.) Intraspecific Variation and Thermotolerance Classification Using in Vitro Seed Germination Assay," American Journal of Plant Sciences, Vol. 2 No. 2, 2011, pp. 134-147. doi: 10.4236/ajps.2011.22015.


[1] Hacisalihoglu, G., “Responses of three switchgrass (Panicum virgatum L.) cultivars to seed priming and differential aging conditions,” Acta Agriculturae Scandinavica Section B-Soil and Plant Science, Vol. 58, No. 3, 2008, pp. 280-284.
[2] Aiken, G.E. and T. L. Springer, “Seed size distribution, germination, and emergence of six switchgrass cultivars,” Journal of Range Management, Vol. 48, 1995, pp. 455-458.
[3] Hsu, F. H., C. J. Nelson, and W. S. Chow, “A mathematical model to utilize the logistic function in germination and seedling growth,” Journal of Experimental Botany, Vol. 35, 1984, pp. 1629-1640.
[4] Robocker, W., J. Curtis, and H. Ahlgren, “Some factors affecting emergence and establishment of native grass seedlings in Wisconsin,” Ecology, Vol. 34, No. 1, 1953, pp. 194-199.
[5] Hanson, J. D. and H. A. Johnson, “Germination of switchgrass under various temperature and pH regimes,” Seed TechNology, Vol. 27, No. 2, 2005, pp. 203-210.
[6] Fulbright, T. E., “Effects of temperature, water potential, and sodium chloride on Indiangrass germination,” Journal of Range Management, Vol. 41, No. 3, 1988, pp. 207-210.
[7] McLaughlin, S. B. and M. E. Walsh, “Evaluating environmental consequences of producing herbaceous crops for bioenergy,” Biomass and Bioenergy, Vol. 14, No. 4, 1998, pp. 317-324.
[8] Das, M. K., R. G. Fuentes, and C. M. Taliaferro, “Genetic variability and trait relationships in switchgrass,” Crop Science, Vol. 44, No. 2, 2004, pp. 443-448.
[9] Eberhart, S. A. and L. C. Newell, “Variation in domestic collections of switchgrass, Panicum virgatum L.,” AgroNomy Journal, Vol. 51, No. 10, 1959, pp. 613-616.
[10] Casler, M. D., et al., “Latitudinal and longitudinal adaptation of switchgrass populations,” Crop Science, Vol. 47, No. 6, 2007, pp. 2249-2260.
[11] Roberts, E. H., “Temperature and seed germination,” in Plants and temperature, S. P. Long and F. I. Woodword, Editors, Symposia of the Society for Experimental Biology, Cambridge, UK, 1988. pp. 109-132.
[12] Jordan, G. L. and M. R. Haferkamp, “Temperature responses and calculated heat units for germination of several range grasses and shrubs,” Journal of Range Management, Vol. 42, No. 1, 1989, pp. 41-45.
[13] Ellis, R., E. Roberts, and P. Hebblethwaite, “Towards a rational basis for testing seed quality,” in Seed Production, P. Hebblethwaite, Editor, Butterworths, London, 1980. pp. 605-635.
[14] Parrish, D. J. and J. H. Fike, “The biology and agroNomy of switchgrass for biofuels,” Critical Reviews in Plant Sciences, Vol. 24, 2005, pp. 423-459.
[15] Hsu, F. H., C. J. Nelson, and A. G. Matches, “Temperature effects on germination of perennial warm-season forage grasses,” Crop Science, Vol. 25, No. 2, 1985, pp. 215-215.
[16] Kiniry, J. R., et al., “Switchgrass simulation by the ALMANAC model at diverse sites in the southern US,” Biomass and Bioenergy, Vol. 29, No. 6, 2005, pp. 419-425.
[17] Heaton, E., T. Voigt, and S. P. Long, “A quantitative review comparing the yields of two candidate C4 perennial biomass crops in relation to nitrogen, temperature and water,” Biomass and Bioenergy, Vol. 27, No. 1, 2004, pp. 21-30.
[18] McLaughlin, S., et al., “Developing switchgrass as a bioenergy crop,” in Perspectives on New Crops and New Uses, J. Janick, Editor, ASHS Press, Alexandria, VA, 1999. pp. 282-289.
[19] Setimela, P. S., et al., “Screening sorghum seedlings for heat tolerance using a laboratory method,” European Journal of AgroNomy, Vol. 23, No. 2, 2005, pp. 103-107.
[20] Bouslama, M. and W. T. Schapaugh Jr, “Stress tolerance in soybeans. I. Evaluation of three screening techniques for heat and drought tolerance,” Crop Science, Vol. 24, No. 5, 1984, pp. 933-933.
[21] Sadasivam, S., et al., “Genetic variation in seed germination, root traits and drought recovery in rice,” Indian Journal of Plant Physiology, Vol. 5, No. 1, 2000, pp. 73-78.
[22] Foolad, M. R. and G. Y. Lin, “Genetic potential for salt tolerance during germination in Lycopersicon species,” HortScience, Vol. 32, 1997, pp. 296-300.
[23] Misra, N. and U. N. Dwivedi, “GeNotypic difference in salinity tolerance of green gram cultivars,” Plant Science, Vol. 166, No. 5, 2004, pp. 1135-1142.
[24] Hou, F. F. and F. S. Thseng, “Studies on the screening technique for pre-germination flooding tolerance in soybean,” Japanese Journal of Crop Science, Vol. 61, No. 3, 1992, pp. 447-453.
[25] Acharya, S. N., J. Dueck, and R. K. Downey, “Selection and heritability studies on caNola/rapeseed for low temperature germination,” Canadian Journal of Plant Science, Vol. 63, 1983, pp. 377-384.
[26] Tiryaki, I. and D. J. Andrews, “Germination and seedling cold tolerance in sorghum. I. Evaluation of rapid screening methods,” AgroNomy Journal, Vol. 93, 2001, pp. 1386-1391.
[27] Covell, S., et al., “The influence of temperature on seed germination rate in grain legumes. I. A comparison of chickpea, lentil, soyabean and cowpea at constant temperatures,” Journal of Experimental Botany, Vol. 37, No. 5, 1986, pp. 705-715.
[28] Emerson, B. N. and H. C. MiNor, “Response of soybeans to high temperature during germination,” Crop Science, Vol. 19, No. 4, 1979, pp. 553-553.
[29] Koti, S., et al., “Soybean (Glycine max) pollen germination characteristics, flower and pollen morphology in response to enhanced ultraviolet-B radiation,” Annals of Botany, Vol. 94, No. 6, 2004, pp. 855.
[30] Salem, M. A., et al., “Pollen-based screening of soybean geNotypes for high temperatures,” Crop Science, Vol. 47, No. 1, 2007, pp. 219-231.
[31] Kakani, V. G., et al., “Response of in vitro pollen germination and pollen tube growth of groundnut (Arachis hypogaea L.) geNotypes to temperature,” Plant Cell and Environment, Vol. 25, No. 12, 2002, pp. 1651-1661.
[32] Kakani, V. G., et al., “Differences in in vitro pollen germination and pollen tube growth of cotton cultivars in response to high temperature,” Ann. Bot., Vol. 96, No. 1, 2005, pp. 59-67.
[33] Singh, S. K., et al., “Assessment of cold and heat tolerance of winter-grown caNola (Brassica napus L.) cultivars by pollen-based parameters,” Journal of AgroNomy and Crop Science, Vol. 194, No. 3, 2008, pp. 225-236.
[34] Shen, Z. X., et al., “Stratification in switchgrass seeds is reversed and hastened by drying,” Crop Science, Vol. 41, No. 5, 2001, pp. 1546-1551.
[35] Systat Software Inc., “SigmaPlot 10.0 – User’s Guide. Point Richmond, CA, USA.” 2006.
[36] SAS Institute Inc., “SAS/STAT User’s Guide, Version 9.1.3.” 2004, SAS Institute Inc., Cary, NC.
[37] Schimpf, D. J., S. D. Flint, and I.G. Palmblad, “Representation of germination curves with the logistic function,” Annals of Botany, Vol. 41, No. 6, 1977, pp. 1357-1360.
[38] Roundy, B. A. and S. H. Biedenbender, “Germination of warm-season grasses under constant and dynamic temperatures,” Journal of Range Management, Vol. 49, 1996, pp. 425-431.
[39] Sabo, D. G. and R. M. Forest, “Germination requirements of 19 species of arid land plants,” Rocky Mountain Forest and Range Experiment Station, Forest Service, US Dept. of Agriculture, 1979.
[40] Madakadze, I. C., et al., “Variation in base temperatures for germination in warm season grasses,” Seed Science and TechNology, Vol. 29, No. 1, 2001, pp. 31-38.
[41] Probert, R., “The role of temperature in the regulation of seed dormancy and germination,” in Seeds: The Ecology of Regeneration in Plant Communities, M. Fenner, Editor, CABI Pub., Wallingford, UK, 2000. pp. 261-292.
[42] Covell, S., et al., “The influence of temperature on seed germination rate in grain legumes. I. A comparison of chickpea, lentil, soyabean and cowpea at constant temperatures,” Journal of Experimental Botany, Vol. 37, No. 5, 1986, pp. 705-715.
[43] Garcia-Huidobro, J., J. L. Monteith, and G. R. Squire, “Time, Temperature and Germination of Pearl Millet (Pennisetum typhoides S. & H.) I. Constant temperature,” Journal of Experimental Botany, Vol. 33, No. 2, 1982, pp. 288-296.
[44] Benech-ArNold, R. L., et al., “Temperature effects on dormancy release and germination rate in Sorghum halepense (L.) Pers. seeds: a quantitative analysis,” Weed Research, Vol. 30, No. 2, 1990, pp. 81 - 89.
[45] Hardegree, S. P., “Predicting germination response to temperature. I. Cardinal-temperature models and subpopulation-specific regression,” Annals of Botany, Vol. 97, No. 6, 2006, pp. 1115-1125.
[46] Lopez, M., et al., “The effect of temperature and water stress on laboratory germination of Eucalyptus globulus Labill. seeds of different sizes,” Annals of Forest Science, Vol. 57, No. 3, 2000, pp. 245-250.
[47] Reddy, K. R. and V. G. Kakani, “Screening Capsicum species of different origins for high temperature tolerance by in vitro pollen germination and pollen tube length,” Scientia Horticulturae, Vol. 112, No. 2, 2007, pp. 130-135.
[48] El-Kassaby, Y. A., et al., “Seed germination: Mathematical representation and parameters extraction,” Forest Science, Vol. 54, No. 2, 2008, pp. 220-227.
[49] Copeland, L. and M. B. McDonald, “Principles of Seed Science and TechNology,” 4th ed., Norwell, MA, Springer, 2001.
[50] Casler, M. D. and A. R. Boe, “Cultivar x environment interactions in switchgrass,” Crop Science, Vol. 43, 2003, pp. 2226-2233.
[51] Casler, M. D., et al., “Latitudinal adaptation of switchgrass populations,” Crop Science, Vol. 44, No. 1, 2004, pp. 293-303.
[52] Orozco-Segovia, A., et al., “A mathematical model that uses Gaussian distribution to analyze the germination of Manfreda brachystachya (Agavaceae) in a thermogradient,” Physiologia Plantarum, Vol. 98, No. 3, 1996, pp. 431-438.
[53] Moser, L. E. and K. P. Vogel, “Switchgrass, big bluestem, and indiangrass,” in Forages: An Introduction to Grassland Agriculture, R.F. Barnes, D.A. Miller, and C.J. Nelson, Editors, Iowa State Univ. Press, Ames, IO, 1995, pp. 409-420.
[54] Mitchell, R. and L. Moser, “Developmental morphology and tiller dynamics of warm-season grass swards,” in Native Warm-Season Grasses: Research Trends and Issues, K. J. Moore and B. A.

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