Micropropagation and in vitro Conservation via Slow Growth Techniques of Prunus webbii (Spach) Vierh: An Endangered Plant Species in Albania

Wild almond is a woody species, which is difficult to propagate either generatively by seed or by vegetative methods (grafting or cuttings) and also considered as Endangered (EN) in Albania based on IUCN criteria. As a wild relative of cultivated fruit trees, this species represents a source of genetic variability and can be very important in breeding programs and cultivation. For this reason, it would be of interest to use an effective method of in vitro mid-term conservation, which involves strategies to slow plant growth through physicochemical alterations of in vitro growth conditions. Multiplication of wild almond was carried out using zygotic embryos, as primary explants, with the purpose to develop a successful propagation protocol. Results showed that zygotic embryos can proliferate through direct or indirect organogenesis. During subculture, stage was obtained a great number of new plantlets identical to mother plants derived from the zygotic embryos. All in vitro plantlets obtained from subcultures underwent in vitro conservation by minimal growth in low temperature (4ºC) and darkness. The efficiency of this technique was evaluated for 3, 6, and 10 months of conservation period. Maintenance in these conditions reduced micro cuttings growth. Survival and regeneration rates for each period were evaluated and resulted that the maximal time of conservation without subculture on 4ºC was 10 months, but survival and regeneration rates were significantly reduced, specifically 15.6% and 7.6%. An optimal period of conservation in these conditions can be considered the 5-6 months storage, which can lead to 60-50% of survival and regeneration rates. This protocol may be beneficial for mass propagation, mid-term conservation, and for genetic manipulation of wild almond.





References:
[1] J. Vangjeli, B. Ruci, A. Mullaj, “Libri i Kuq. Bimët e kërcënuara dhe të rralla të Shqipërisë”. 1995.
[2] XH. Qosja, K. Paparisto. M. Demiri, J. Vangjeli, E. Balza, “Flora e Shqipërisë 4”, Akademia e Shkencave të Republikës së Shqipërisë. Qendra e Kërkimeve Biologjike, 1992, Tiranë.
[3] G. Ladizinsky, On the origin of almond, Genetic Resources and Crop Evolution. 1999, 46:143–147.
[4] D. Zohary, M. Hopf, “Domestication of plants in the old world”, Clarendon Press, 1993, Oxford.
[5] E. F. Fang, N. Tzi Bun, “Ribonucleases of different origins with a wide spectrum of medicinal applications”. School of Biomedical Sciences, Faculty of Medicine, Chinese University of Hong Kong, 2010. Shatin, Hong Kong.
[6] A. B. Russell, J. W. Hardin, L. Grand. “Poisonous Plants of North Carolina”. North Carolina State University. 1997.
[7] J. Vangjeli, “Udhëheqës fushor i Florës së Shqipërisë”, Akademia e Shkencave të Republikës së Shqipërisë. Instituti i kërkimeve Biologjike, 2003, Tiranë.
[8] E. Kongjika, ZH. Zekaj, E. Çaushi, I. Stamo, “Bioteknologjia e bimëve – Kulturat “in vitro”, Akademia e Shkencave, 2002, 97 – 105;
[9] C. Damiano, M. D. Arias Padro, A. Frattarelli, Propagation and establishment in vitro of myrtle (Myrtus communis L.), pomegranate (Punica granatum L.) and mulberry (Morus alba L.), Propagation of Ornamental Plants, 2008, 8 (1): 3-8.
[10] M. E. Daorden, J. A. Marín, A. Arbeloa, Stratification Temperature affects the in vitro Germination of Immature Prunus Embryos, ISHS Acta Horticultura, 2004, 658, vol. 2: 135-140;
[11] A.H. Neveen, S. A. Bekheet, Mid-term storage and genetic stability of Strawberry tissue cultures. Research Journal of Agriculture and Biological Sciences, 2008, 4(5): 505 – 511.
[12] N. R. Kameswara, Plant genetic resources: Advancing conservation and use through biotechnology, African Journal of Biotechnology, Vol. 3(2). 2004, (pp. 136 - 145).
[13] A. Maqsood, A. A. Muhamad, H. S. Asad, A. Abdul, In vitro preservation of Pyrus germplasm with minimal growth using different temperature regimes, Pak. J. Bot., 2010, 42(3): 1639 – 1650.
[14] W. T. Muriithi, I. S. Harry, E. C. Yeung, T. A. Thorpe, Plantlet regeneration in chir pine (Pinus roxburghii Sarg): morphogenesis and histology, Forest Ecol. Manag. 1995, 57, 141–160.
[15] T. Murashige, F. Skoog, A revised medium for rapid growth and bioassays with tobacco tissue cultures, Physiol. Plant. 1962, 15: 473 – 497.
[16] B. M. Reed, Cold storage of strawberries in vitro: a comparison of three storage systems, Fruit varieties Journal, 1992, 46(2): 98 – 102.
[17] V. Raghavan, P. S. Srivastava, “Embryo culture. In: Johri, B. M., ed. Experimental embryology of vascular plants”, Berlin: Springer-Verlag; 1982:195–230.
[18] G. Corsi, The suspensor of Eruca sativa Miller (Cruciferae) during embryogenesis in vitro, Giorn. Bot. Ital. 1982, 106:41–54.
[19] E. C. Yeung, I. M. Sussex, “Embryogeny of Phaseolus coccineus: the suspensor and the growth of the embryo-proper in vitro”. Z. Pflanzenphysiol. 1979, 91:423–433.
[20] M. Monnier, Survival of young immature Capsella embryos cultured in vitro, J. Plant Physiol. 115:105–113; 1984.
[21] C. R. Sánchez-Romero, B. Perán-Quesada, A. Márquez-Martín, A. Barceló-Muñoz, F. Pliego-Alfaro, In vitro rescue of immature avocado (Persea Americana mill.) embryos, Sci. Hort. 2007, 111:365-370
[22] P. Maheshwari, B. Baldev, Artificial production of buds from the embryos of Cuscuta reflexa, Nature, 1961, 191:197–198.
[23] A. S. Muna, A. K. Ahmad, K. Mahmoud, K. Abdul Rahman, In vitro propagation of a semi-dwarfing cherry rootstock, Plant Cell, Tissue and Organ Culture, 1999, 59: 203–208.
[24] K. W. Pruski, T. Lewis, T. Astatkie, J. Nowak, Micropropagation of Chokecherry and Pincherry cultivars, 2000, Plant Cell, Tissue and Organ Culture, 63: 93–100.
[25] M. Saponari, G. Bottalico, G. Savino, In vitro propagation of Prunus mahaleb and its sanitation from Prune dwarf virus. Advances in Horticultural Science”, 1999, 13:56–60.
[26] H. Yildirim, E. Tilkat, A. Onay, H.Ç. Ozen, In Vitro Embryo Culture of Apricot, Prunus armeniaca L. cv. Hacıhaliloglu, International Journal of Science & Technology, 2007, Volume 2, No 2, 99-104.
[27] M. N. Nas, Y. Bolek, “Short Cut to Long Distance: Developing an Almond Micropropagation Medium”, 5th International Symposium on Pistachios and Almonds – ISHS – Sanliurfa – Turkey, 2009, Book of Abstracts, p. 230.
[28] M. Nas, P. E. Read, A hypothesis for the development of a defined tissue culture medium for higher plants and micro-propagation of hazelnuts, Scientia Horticulturae, 2004, 101:189-200.
[29] R. W. Tahtamouni, R. A. Shibli, Preservation at low temperature and cryopreservation in wild pear (Pyrus syriaca). Adv. Hortic. Sci., 1999, 13: 156-160.
[30] C. Lundergan, J. Janick, Low temperature storage of in vitro apple shoots, Hort Science, 1979, 14: 514.
[31] W. H. Wanas, J. A. Callow, L. A. Withers, “Growth limitation for the conservation of pear genotypes”. In: Plant Tissue Culture and Its Agricultural Applications. Butterworth, London, 1986, pp. 285-290.
[32] R. L. Bell, B. M. Reed, In vitro tissue culture of pear: advances in techniques for micropropagation and germplasm preservation, Acta Horti. 2002, 596: 412-418.
[33] V. Negri, N. Tosti, A. Standardi, Slow growth storage of single node shoots of apple genotypes, Plant Cell Tissue Org. Cult., 2000, 62: 159-162.
[34] T. Orlikowska, Effect of in vitro storage at 4oC on survival and proliferation of two apple rootstocks, Plant Cell, Tissue and Organ Cult. 1992, 31: 1–7.