Document Type : Original Article

Abstract

To investigate the role of mucilage in germination of medicinal plants in drought stress conditions, germination test conducted on 4 replications of 25 seeds of 13 species of medicinal plants with mucilage from the families of Lamiaceae, Brassicaceae, Fabaceae, Linaceae and Plantaginaceae in 9 cm diameter petridishes with filter paper premoistined with distilled water in the Seed Laboratory, Faculty of Agriculture, Ferdowsi University of Mashhad in 2012. Different levels of waterpotential (0, -0.1, -0.2, -0.3, -0.4 MPa) using PEG applied and germination percent and mean germination time (MGT) of the species were determined.Results showed osmotic potential levels had a significant effect on the germination percent and mean germination time (MGT) of the species (P≤0.01). P. psylliumM. officinalis and L. usitatissimum were tolerant while, S.officinalis,A.homalocarpum and P.major were sensitive species and other species showed moderate tolerance. It seems amount of the mucilage of species was effective on tolerance of the species. The positive effect of the mucilage on the reduction of stress in the majority of the species may have an ecological benefit in the harsh conditions for the germination of the species with mucilage.

Keywords

Aghilian, S.H. 2010. Assessment of the seed dormancy and storage potential of forty medicinal plant species
grown in Iran. MSc Thesis. Faculty of Agriculture, the University of Ferdowsi University of Mashhad, Iran. [In Persian with English summary].
Boromand- Reza Zadeh, Z., and A. Koocheki, 2005. Response of seed germination Ajowan, fennel, dill
Salt stress due to matric and osmotic potential of polyethylene glycol 6000 at different temperatures. Agron. Res. Iran. 3(2): 207-217. irak, C., K. Kevseroglu, and A.K. Ayan, 2007.
Breaking of seed dormancy in a Turkish endemic
Hypericum species: Hypericum aviculariifolium subsp. depilatum var. depilatum by light and some pre- soaking treatments. J. Arid Environ. 68(1): 159-164. Emami, A., and Z. Tayrani Najaran, 2008. Pharmacognosie Phytochimie Plantes Medicinales. Mashhad
University of Medical. 143pp. [In Persian]. Ghani, A., M. Azizi and A. Tehranifar, 2009. Response of Achillea specie to drought stress induce by
polyethylene glycol in germination stage. Iran. J. Aromatic Plants. 25(2): 261-271. Hassani, A. 2005. Effects of water stress induced by polyethylene glycol on germination characteristics of
basil (Ocimum basilicum). Iran. J. Aromatic Plants. 21: 535-543. Hosseini, H., and P. Rezvani-Moghadam, 2006. Effect of water and salinity stress in seed germination of
Isabgol (Plantago ovata). Agron. Res. Iran. 4: 15-22. Huang, Z., Y. Gutterman and Z. Hu, 2000. Structure and function of mucilaginous achenes of Artemisia
monosperma in habiting the Negev Desert of Israel. Isr. J. Plant Sci. 48: 265-266. Huang, Z., Y. Gutterman and D. J. Osborne, 2004. Value of the mucileginous pellicle to seeds of the sand
stabilizing desert woody shrub Artemisia sphaerocephala (Astraceae). Trees, 18: 669-676. Huang, Z., I. Babriak, D.J. Osborne, M. Dong and Y. Gutterman, 2008. Possible role of Pectin ñ Containing mucilage and dew in repairing embryo DNA of seeds adapted to desert conditions. Ann. Bot. 101: 277 ñ 283. James, A., Young and Raymond, A. Evans, 1973. Mucilaginus Seed Coats. Weed Sci. 21(1): 52-54. Michel, B. E., and M. R. Kaufmann, 1973. The osmotic potential of polyethylene glycol 6000, Plant Physiol. 51:914-916. Penfield, S., R.C. Meissner, D.A. Shoue, N.C. Carpita and M.W. Bevan, 2001. MYB61 is required for
mucilage deposition and extrusion in the Arabidopsis seedcoat. Plant Cell. 13: 2777-2791. Rautengarten, C., B. Usadel, I. Neumetzler, J. Hartmann, D. Bussis and T. Altmann, 2008. Asubtilisin -
like serine protease essential for mucilage release from Arabidopsis seedcoats. Plant J. 54: 466-480. Thapliyal, R.C., S.S. Plartyal and j. M. Baskin, 2006. Role of mucilage in germination of Dillenia indica
(Dilleniaceae) seeds. Aust. J. Bot. 56: 583 ñ 589. Toncer, O.G., and S. Tansi, 2000. The caper (Capparis ovata) culture in Turkey. Pak. J. Biol. Sci. 3: 568- 570. Yang, x., M. Dong and Z. Huang, 2010. Role of mucilage in the germination of Artemizia sphaerocephala
(Astraceae) achenes exposed to osmotic stress and salinity. Plant Physiol. Biochem. 48: 131- 135.