Ecophysiological role of mucilaginous seed coat on germination and seedling growth of Balangu (Lallemantia royleana) imposed to drought and salinity stress

Document Type : Original Article

Authors

Abstract

It seems mucilaginous seed coat is an aspect of plants evolutionary adaptation to desert environments. Because of mucilage production, seed coat of Balangu Shirazi (Lallemantia royleana) absorbs water multiple times more than of its initial weight. To determine the possible role of mucilaginous seed coat, two mucilaginous (M) and demucilaged (DM) seeds were examined in two separate experiments of drought with six levels (0 as control, -0.1, -0.2, -0.3, -0.4,and -0.5 MPa) and salinity with six levels (0 as control, 2, 4, 6, 8, and 10 ds.m-1) through factorial experiment as completely randomized design with three replications of 25 seeds. Germination of demucilaged seeds significantly was higher than mucilaginous seed in drought trial; though in salinity stress, there was no significant difference between germination of mucilaginous and demucilaged seeds. Mean germination time (MGT) in mucilaginous seeds was higher than the demucilaged seeds in both salinity and drought stresses. In salinity experiment, length of root, stem and stem/root length ratio in mucilaginous seed was higher than the demucilaged seed significantly; while there was no any differences in drought stress. Interaction of seed with drought was not significant but there was significant interaction between seed and salinity.

Keywords


Arsovski, A.A., M.M.Villota, O. Rowland, R. Subramaniam, and T.L.Western. 2009. Mum enhancers are important for seed coat mucilage production and mucilage secretory cell differentiation in Arabidopsis thaliana. J. Exp. Bot. 60: 2601–2612.
Fahn, A.1990. Plant Anatomy, fourth ed. Pergamon Press, Oxford.
Garwood N.C. 1985. The Role of mucilage in the germination of Cuipo, Cavanillesia platanifolia (H. & B.) HBK (Bombacaceae), A tropical tree. Am. J. Bot. 72: 1095-1105.
Gutterman, Y. 1993. Seed Germination in Desert Plants. Berlin: Heidelberg: Springer-Verlag.
Harper, J.L., and R.A. Benton. 1966. The behaviour of seeds in soil II. The germination of seeds on the surface of a water supplying substrate. J. Ecol. 54: 151-166.
Hajrezaie, M., H. Sodaeizade, A.M. Mirmohammadi Meibodi, and A. Mosleh Arani. 2012. The role of mucilage in improving germination and early growth of plants under drought stress (Case study: Plantago ovata and Plantago major). Arid Biomed. Sci. Res. J. 2: 12-24. (In Persian, with English Abstract.).
Hasegawa, P.M., R.A. Bressan, J.K. Zhu, and H.J. Bohnert. 2000. Plant cellular and molecular responses to high salinity. Annu. Rev. Plant Physiol. Plant Mol. Biol. 51:463–99.
Heydecker, W., and P. Orphanos. 1968. The effect of excess moisture on the germination of Spinacia oleracea L. Planta. 83: 237–247.
Hosseini, H., and P. Rezvani Moghadam. 2006. Effect of water and salinity stress in seed germination on Isabgol (Plantago ovata). Iranian J. Field Crops Res. 4: 15-22. (In Persian, with English Abstract.)
Huang, Z., I. Boubriak, D.J. Osborne, M. Dong, and Y. Gutterman. 2008. Possible role of pectin-containing mucilage and dew in repairing embryo DNA of seeds adapted to desert conditions. Ann. Bot. 101: 277–283.
Huang, Z., and Y. Gutterman. 1998. Artemisia monosperma achene germination in sand: effects of sand depth, sand/water content, cyanobacterial sand crust and temperature. J. Arid Environ. 38: 27–43.
Khajeh-Hosseini, M., A. Lomholt, and S. Matthews. 2009. Mean germination time in the laboratory estimates the relative vigour and field performance of commercial lots of maize. Seed Sci.Technol. 37: 446-461.
Khajeh-Hosseini, M., and T. Mostashar-Shahidi. 2016. Role of mucilage in germination of fourteen species of medicinal plants. Seed Sci. Technol. 44: 435-440.
Kreitschitz, A., and J. Va`lles . 2007. Achene morphology and slime structure in some taxa of Artemisia L. and Neopallasia L. (Asteraceae). Flora. 202: 570–580.
Li X., D. Jiang, Z. Liu, and Q. Yu. 2008. Annual plants in arid and semi-arid desert regions. Front. Biol. China. 3: 259–264.
Michel, B.E., and Kaufmann, M. R. 1973. The osmotic potential of polyethylene glycol 6000. Plant Physiol. 51: 914-917.
Mott, J. 1974. Factors affecting seed germination in three annual species from an arid region of Western Australia. J. Ecol. 62: 699–709.
Mozaffarian, V. 1996. A Dictionary of Iranian Plant Names: Latin, English, Persian. Farhang-e Moaser, Tehran.
Niknam, V. 1999. Identification of secondary metabolits (N-aliphatic composition, mucilage polyssacharides, saponines, sterols, phenolic compositions). Ph.D. Thesis, Faculty of Science, Tehran University. (In Persian, with English Abstract).
Osunkoya, O.O., J.E. Ash, M.S. Hopkins, and A.W. Graham. 1994. Influence of seed size and seedling ecological attributes on shade-tolerance of rain-forest tree species in northern Queensland. J. Ecol. 82: 149–163.
Sohrabizadeh, Z., H. Sodaeizadeh, and A. Mosleh Arani. 2015. Effect of mucilage on salinity tolerance of Lallemantia ibrica at seed germination stage. Iranian J. Filed Crops Sci. 46: 463-472.1(In Persian, with English Abstract). 2
Thapliyal, R.C., S.S. Phartyal, J.M. Baskin, and C.C. Baskin. 2008. Role of mucilage in germination of Dillenia indica (Dilleniaceae) seeds. Aust. J. Bot. 56: 583-589.
Uhvits, R. 1946. Effect of osmotic pressure on water absorption and germination of alfalfa seeds. Am. J. Bot. 33: 278–285.
Werner J.E., and R.R. Finkelstein. 1995. Arabidopsis mutants with reduced response to NaCl and osmotic stress. Physiol. Plant. 93: 659-666.
Western, T.L. 2012. The sticky tale of seed coat mucilages: production, genetics, and role in seed germination and dispersal. Seed Sci. Res. 22: 1–25.
Witztum, A.,Y. Gutterman, and M. Evenari. 1969. Integumentary mucilage as an oxygen barrier during germination of Blepharis persica (Burm.) Kuntze. Bot. Gaz. 130: 238-241.
Yang, X., J.M. Baskin, C.C. Baskin, and Z. Huang. 2012. More than just a coating: ecological importance, taxonomic occurrence and phylogenetic relationships of seed coat mucilage. Perspect. Plant Ecol. 14: 434–442.
Yang, X., M. Dong, and Z. Huang, 2010.Role of mucilage in the germination of Artemisia sphaerocephala (Asteraceae) achenes exposed to osmotic stress and salinity. Plant Physiol. Biochem. 48: 131–135.
Zhou, D. 2012. Seed germination performance and mucilage production of sweet basil (Ocimum basilicum L.). Master of Science Thesis In Horticulture. Blacksburg, Virginia
Zhou, D., M. Ponder, J. Barney, and G. Wlbaeum. 2016. Germination response of six sweet basil (Ocimum bacilicum) cultivars to temperature. Seed Tech. 37(1): 43-51.