Effects of Salinity and Drought Levels in Seed Germination of Five Crop Species

Authors: Ahmad Gholami, Saeed Sharafi, Hamid Abbasdokht

Abstract:

The heterotrophic seedling growth can be defined as a product of two components: (1) the weight of mobilized seed reserve, and (2) conversion efficiency of utilized seed reserve to seedling tissue. The first component can be further divided into (1) initial seed weight, and (2) the fraction of seed reserve, which is mobilized. The objective of this study was the identification of the sensitive seedling growth component(s) in response to drought and salinity stresses. Two experiments were separately conducted using various salinity levels (osmotic pressure) of 0, 0.25, 0.50, 0.75, 1, 1.25 and 1.5 MPa created using NaCl as first experiment and by polyethylene glycol (drought stress) of 0, 0.2, 0.4, 0.6, 0.8, 1, 1.2 and 1.4 MPa in second experiment. Seeds of five crops species (Hordeum vulgare, Brassica napus, Zea mays, Medicago sativa and Medicago scutellata) were used in each experiment. In both experiments, seedling growth, fraction of seed reserve utilization and weight of mobilized seed reserve decreased with increasing drought and salt intensity. However, drought and salinity stresses had no effect on the conversion efficiency. It was concluded that the sensitive component of seedling growth is the weight of mobilized seed reserve.

Keywords: Salinity, Drought, Seed reserve, Seedling, Cropsspecies

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1055142

References:

[1] Ashraf, M., McNeily, T., 1988. Variability in salt tolerance of nine spring wheat cultivars. J. Agron. Crop Sci. 160, 14-21
[2] Beveridge, J.L., Wilise, C.P., 1959. Influence of depth of planting, seed size and variety on emergence and seedling vigor in alfalfa. Agron. J. 51, 731-734.
[3] Bockous, W.W., Shroyer, J.P., 1996. Effect of seed size on seedling vigor and forage production of winter wheat. Can. J. Plant Sci. 76, 101- 105.
[4] Carter, T.E., Jr., P.I. DeSouza, and L.C. Purcell. 1999. Recent advances in breeding for drought and aluminum resistance in soybean. P. 106-125. In H.E. Kauffman (ed). Proc. Of World Soybean Res. Conf., VI, Chicago. 4-7 Aug. 1999. Superior Print., Champaign, IL.
[5] Condon, A.G., Richards, R.A., Farquhar, G.D., 1993. Relationships between carbon isotope discrimination, water use efficiency and transpiration efficiency for dry land wheat. Aust. J. Agric. Res. 44, 1693-1711.
[6] Davidson, D.J., Chevalier, P.M., 1987. Influence of polyethylenglycol induced water deficits on tiller production in spring wheat. Crop Sci. 27, 1185-118.
[7] Douglas, C.L., Wilkins, D.E., Churchill, D.B., 1994. Tillage, seed size and seed density effects on performance of soft white winter wheat. Agron. J. 86, 707-711.
[8] Francois, L.E., Maas, E.V., Donovan, T.J., Young's, V.L., 1986. Effects of salinity on grain yield and quality, vegetative growth and germination of semi dwarf and drum wheat. Agron. J. 78, 1053-1058.
[9] Goydani, B.M., Singh, C., 1971. Influence of seed size on growth and yield of wheat. Indian J. Agron. 16, 209-212.
[10] Grieve, C.M., Francois, L.E., 1992. The importance of initial seed size in wheat plant response to salinity. Plant Soil 147, 197-205.
[11] Guedira, M., Shroyer, J.P., Kirkham, M.B., Paulsen, G.M., 1997. Wheat coleoptile and root growth and seedling survival after dehydration and rehydration. Agron. J. 89, 822-826.
[12] Hampson, C.R., Simpson, G.M., 1990. Effects of temperature, salt and osmotic pressure on early growth of wheat (Triticum aestivum). 1. Germination. Can. J. Bot. 68, 524-528.
[13] Hegary, T.W., Ross, H.A., 1976. Effects of light and water deficit on radicle growth of lettuce seeds under high temperature stress. New Phytol. 82, 49-57.
[14] Johnson, D.R.,Wax, L.M., 1978. Relationships of soybean germination and vigor tests to field performance. Agron. J. 70, 273-278.
[15] Kiem, D.L., Krostad, W.E., 1981. Drought response of winter wheat cultivars grown under field stress conditions. Crop Sci. 21, 11-15.
[16] Lafond, G.P., Backer, R.J., 1986. Effects of temperature, moisture stress, and seed size on germination of nine spring wheat cultivars. Crop Sci. 26, 563-567.
[17] Peterson, C.M., Klepper, B., Rickman,R.W., 1989. Seed reserves and seedling development in winter wheat. Agron. J. 81, 245-251.
[18] Purcell, L.C., and J.E. Specht. 2003. Physiological traits for ameliorating water-deficit stress. In H.R. Boerma and J.E. Specht (ed). Soybean: Improvement, production, and uses (in press). 3rd ed. Agron. Monogr. 16. ASA, CSSA, and SSSA, Madison, WI.
[19] Randhawa, A.S., Anand, S.C., Jolly, R.S., 1974. Effect of seed-size and seed-rate on wheat yield. J. Res. 11, 9-12.
[20] Serraj, R., and T.R. Sinclair. 2002. Osmolyte accumulation: Can it really help increase crop yield under drought conditions? Plant Cell Environ. 25: 333-341.
[21] Shroyer, J.P., Cox, T.S., 1984. Effects of cultivar, environment and their interaction on seed quality of hard red winter wheat from production fields. J. Appl. Seed Prod. 2, 24-28.
[22] Singh, B.P., 1970. Influence of seed size and depth of sowing on early growth and yield of dwarf wheat. Madras Agric. J. 57, 449-452.