Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-23T10:02:01.078Z Has data issue: false hasContentIssue false
  • English
  • Français

Soil moisture conditions affect the sensitivity of Bromus catharticus dormant seeds to light and the emergence pattern of seedlings

Published online by Cambridge University Press:  01 June 2009

Federico P.O. Mollard  and
Pedro Insausti
Federico P.O. Mollard*
Affiliation:
IFEVA-CONICET, Facultad de Agronomía, UBA, Av. San Martín 4453, C1417DSEBuenos Aires, Argentina
Pedro Insausti
Affiliation:
IFEVA-CONICET, Facultad de Agronomía, UBA, Av. San Martín 4453, C1417DSEBuenos Aires, Argentina
*
*Correspondence Fax: +54 11 4514-8730 Email: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The soil moisture regime may affect dormancy of seeds and their sensitivity to signals that promote germination. We studied the effect of moisture regime on the sensitivity to light of dormant Bromus catharticus seeds, and on the emergence pattern of seedlings. Seeds were incubated under continuously hydrated, continuously dehydrated, or fluctuating moisture regimes in a controlled environment (25°C, darkness) for 2 months. After moisture treatments, seeds were exposed to red or far-red light pulses, or to darkness, to determine germinability. In addition, grassland mesocosms with intact seed bank and vegetation were irrigated or subjected to a drought regime in a glasshouse at summer temperatures. After 2 months, the temperature was reduced to correspond to grassland temperatures in autumn; the canopy was removed and half of the mesocosms were covered with filters that exclude red light. Density of B. catharticus seedlings was evaluated after 2 weeks. Dormancy decreased in continuously hydrated seeds but they still required red light for germination. In contrast, an important fraction of seeds that experienced continuously dehydrated or fluctuating moisture regimes germinated in darkness or after far-red light pulses. In the mesocosms that had experienced a soil drought, a higher density of seedlings emerged in the absence of red light than in the daily irrigated mesocosms. This indicates that a fraction of B. catharticus seeds acquired the capability to germinate under the canopy, especially in the drought moisture regime. Results indicate that the soil moisture environment experienced during dormancy affects the sensitivity to light of B. catharticus seeds, as well as the emergence pattern of seedlings.

Keywords

Bromus catharticusgerminationgrasslandslightred:far-red ratioseed dormancysoil water availability
Type
Research Article
Information
Seed Science Research , Volume 19 , Issue 2 , June 2009 , pp. 81 - 89
Copyright
Copyright © Cambridge University Press 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Baskin, C.C. and Baskin, J.M. (1998) Ecology of seed dormancy and germination in grasses. pp. 30–83in Cheplick, G.P. (Ed.) Population biology of grasses. Cambridge, Cambridge University Press.Google Scholar
Batlla, D., Nicoletta, M. and Benech-Arnold, R.L. (2007) Sensitivity of Polygonum aviculare seeds to light as affected by soil moisture conditions. Annals of Botany 99, 915–924.CrossRefGoogle ScholarPubMed
Benech-Arnold, R.L., Sánchez, R.A., Forcella, F., Kruk, B. and Ghersa, C.M. (2000) Environmental control of dormancy in weed soil seed banks. Fields Crops Research 67, 105–122.Google Scholar
Bewley, J.D. and Black, M. (1994) Seeds. Physiology of development and germination (2nd edition). New York, Plenum Publishing Corporation.CrossRefGoogle Scholar
Bisigato, A.J. and Bertiller, M.B. (2004) Seedling recruitment of perennial grasses in degraded areas of the Patagonian Monte. Journal of Range Management 57, 191–196.CrossRefGoogle Scholar
Borchert, J.R. (1950) The climate of the central North American grassland. Annals of the Association of American Geographers 40, 1–39.Google Scholar
Borthwick, H.A., Hendricks, S.B., Parker, M.W., Toole, E.H. and Toole, V.K. (1952) A reversible photoreaction controlling seed germination. Proceedings of the National Academy of Sciences 38, 662–666.Google Scholar
Botto, J.F., Scopel, A.L., Ballaré, C.L. and Sánchez, R.A. (1998) The effect of light during and after soil cultivation with different tillage implements on weed seedling emergence. Weed Science 46, 351–357.Google Scholar
Bradford, K. (2005) Threshold models applied to seed germination ecology. New Phytologist 165, 338–341.Google Scholar
Burgos, J.J. and Vidal, A.L. (1951) Los climas de la República Argentina, según la nueva clasificación de Thornthwaite. Meteoros 1, 3–32.Google Scholar
Burkart, S.E. and Sánchez, R.A. (1969) Interaction between an inhibitor present in the seeds of Datura ferox and light in the control of germination. Botanical Gazette 130, 42–47.CrossRefGoogle Scholar
Burkart, S.E., León, R.J.C and Movia, C.P. (1990) Inventario fitosociológico del pastizal de la Depresión del Salado (Prov. de Bs. As.) en un área representativa de sus principales ambientes. Darwiniana 30, 27–69.Google Scholar
Casal, J.J. and Sánchez, R.A. (1998) Phytochromes and seed germination. Seed Science Research 8, 317–329.Google Scholar
Casal, J.J., Luccioni, L.G., Oliverio, K.A. and Boccalandro, H.E. (2003) Light, phytochrome signalling and photomorphogenesis in Arabidopsis. Photochemistry and Photobiological Sciences 2, 625–636.Google Scholar
De Fina, A.L. (1992) Aptitud agroclimática de la República Argentina. Buenos Aires, Academia Nacional de Agronomía y Veterinaria.Google Scholar
Defosse, G.E., Bertiller, M.B. and Robberecht, R. (1997) Effects of topography, soil moisture, wind and grazing on Festuca seedlings in a Patagonian grassland. Journal of Vegetation Science 8, 677–684.Google Scholar
Deregibus, V.A., Casal, J.J., Jacobo, E.J., Gibson, D., Kauffman, M. and Rodriguez, A.M. (1994) Evidence that heavy grazing may promote the germination of Lolium multiflorum seeds via phytochrome-mediated perception of high red/far red ratios. Functional Ecology 8, 536–542.CrossRefGoogle Scholar
Duke, S.O. (1978) Interactions of seed water content with phytochrome-initiated germination of Rumex crispus L. seeds. Plant Cell Physiology 19, 1043–1049.CrossRefGoogle Scholar
Fenner, M. (1980) The induction of a light-requirement in Bidens pilosa seeds by leaf canopy shade. New Phytologist 84, 103–106.Google Scholar
Finch-Savage, W.E. and Leubner-Metzger, G. (2006) Seed dormancy and the control of germination. New Phytologist 171, 501–523.CrossRefGoogle ScholarPubMed
Górski, T., Górska, K. and Nowicki, J. (1977) Germination of seeds of various herbaceous species under leaf canopy. Flora 166, 249–259.CrossRefGoogle Scholar
Hall, A.J., Rebella, C.M., Ghersa, C.M. andCulot, J.P. (1992) Field-crop systems of the Pampas. pp. 413–450in Pearson, C.J. (Ed.) Field crops ecosystem. Ecosystems of the World 18. Amsterdam, Elsevier.Google Scholar
Holmes, M.G. and Smith, H. (1977) The function of phytochrome in the natural environment. II. The influence of vegetation canopies on the spectral energy distribution of natural daylight. Photochemical Photobiology 25, 539–545.CrossRefGoogle Scholar
Hsiao, A.I. and Vidaver, W. (1973) Dark reversion of phytochromne in lettuce seeds stored in a water-saturated atmosphere. Plant Physiology 51, 459–463.Google Scholar
Insausti, P. and Grimoldi, A.A. (2006) Gap disturbance triggers the recolonization of the clonal plant Ambrosia tenufolia in a flooding grassland of Argentina. Austral Ecology 31, 828–836.CrossRefGoogle Scholar
Insausti, P., Soriano, A. and Sánchez, R.A. (1995) Effects of flood-influenced factors on seed germination of Ambrosia tenuifolia. Oecologia 103, 127–132.Google Scholar
James, S.E., Pärtel, M., Wilson, S.D. and Peltzer, D.A. (2003) Temporal heterogeneity of soil moisture in grassland and forest. Journal of Ecology 91, 234–239.CrossRefGoogle Scholar
Jutila, H.M. and Grace, J.B. (2002) Effects of disturbance on germination and seedling establishment in a coastal prairie grassland: A test of the competitive release hypothesis. Journal of Ecology 90, 291–293.CrossRefGoogle Scholar
Kahn, A.A. and Karssen, C.M. (1980) Induction of secondary dormancy in Chenopodium bonus-henricus L. seeds by osmotic and high temperature treatments and its prevention by light and growth regulators. Plant Physiology 66, 175–181.Google Scholar
Lauenroth, W.K., Sala, O.E., Coffin, D.P. and Kirchner, T.B. (1994) The importance of soil water in the recruitment of Bouteloua gracilis in the shortgrass steppe. Ecological Applications 4, 741–749.Google Scholar
Marone, L., Horno, M.E. and González Del Solar, R. (2000) Post-dispersal fate of seeds in the Monte desert of Argentina: patterns of germination in successive wet and dry years. Journal of Ecology 88, 940–949.Google Scholar
Pons, T.L. (1991) Induction of dark dormancy in seeds: its importance for the seed bank in the soil. Functional Ecology 5, 669–675.Google Scholar
Read, T.R. and Bellairs, S.M. (1999) Smoke affects the germination of native grasses of New South Wales. Australian Journal of Botany 47, 563–576.Google Scholar
Rodriguez, A.M., Jacobo, E.J. and Deregibus, V.A. (1998) Germination behaviour of Italian ryegrass in flooding Pampa rangelands. Seed Science Research 8, 521–528.Google Scholar
Rüdiger, W. and Thümmler, F. (1994) The phytochrome chromophore. pp. 51–67in Kendrick, R.E.; Kronenberg, G.H.M. (Eds) Photomorphogenesis in plants (2nd edition). Dordrecht, Martinus Nijhoff Publishers.Google Scholar
Sauer, J. and Struik, G. (1964) A possible ecological relation between soil disturbance, light flash, and seed germination. Ecology 45, 554–556.Google Scholar
Silvertown, J.W. (1980) Leaf-canopy-induced seed dormancy in a grassland flora. New Phytologist 85, 109–118.Google Scholar
Snyman, H.A. (2005) The effect of fire on the soil seed bank of a semi-arid grassland in South Africa. South African Journal of Botany 71, 53–60.Google Scholar
Sokal, R.R. and Rohlf, F.J. (1969) Biometry. San Francisco, Freeman.Google Scholar
Steadman, K.J. (2004) Dormancy release during stratification in Lolium rigidum seeds is dependent on temperature, light quality and hydration status. Journal of Experimental Botany 55, 929–937.CrossRefGoogle ScholarPubMed
Ting, M. and Wang, H. (1997) Summertime U.S. precipitation variability and its relation to Pacific sea surface temperature. Journal of Climate 10, 1853–1873.Google Scholar