Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T07:29:45.772Z Has data issue: false hasContentIssue false

Developmental status is a critical factor in the selection of excised recalcitrant axes as explants for cryopreservation: a study on Trichilia dregeana Sond.

Published online by Cambridge University Press:  22 February 2007

Meagan Goveia
Affiliation:
School of Biological and Conservation Sciences, University of KwaZulu-Natalc2§Durban, 4041, South Africa
Joseph I. Kioko*
Affiliation:
School of Biological and Conservation Sciences, University of KwaZulu-Natalc2§Durban, 4041, South Africa
Patricia Berjak
Affiliation:
School of Biological and Conservation Sciences, University of KwaZulu-Natalc2§Durban, 4041, South Africa
*
*Correspondence Fax: +27 31 260 1195/2029, Email: [email protected]

Abstract

As a consequence of previous lack of success in cryostoring axes excised from newly shed seeds of Trichilia dregeana, the effects of the mode of axis excision on seedling production were investigated. Although vigorous root production occurred, no shoots were produced when the cotyledons were severed as closely as possible to the axis surface (explant-type 0). In contrast, shoot production was increasingly facilitated when small to larger segments of cotyledonary tissue were left attached to the axes (explant-types 1, 2 and 4), which did not compromise axis drying rate. However, root growth of explant-types 1, 2 and 4 was negatively affected, probably by leakage into the medium of an inhibitory or toxic substance(s) from the cut surfaces of the cotyledonary tissue. Microscopical examination revealed that the cotyledons were sessile, and their insertions were contiguous with the shoot apex in axes from newly shed seeds, leading to the suggestion that failure of shoot production by type 0 explants in vitro was the direct consequence of the proximity of the wound sites to the apical meristem. When seeds were stored hydrated for 6 months, the shoot apex had elongated, positioning the apical meristem some distance from the top of the cotyledonary insertions. In contrast to axes excised as type 0 explants from newly shed seeds, the equivalent explants from the stored seeds rapidly formed shoots and leaves in vitro. This indicates that the developmental status of axes, when excised, dictates failure or success in their further development in vitro, and that this aspect needs to be resolved before any further manipulations for cryostorage are attempted.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2004

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

Anguelova-Merhar, V.S., Calistru, C. and Berjak, P. (2003) A study of some biochemical and histopathological responses of wet-stored recalcitrant seeds of Avicennia marina infected by Fusarium moniliforme. Annals of Botany 92, 401408.CrossRefGoogle ScholarPubMed
Beckett, R.P. and Minibayeva, F. (2003) Wounding induces a burst of extracellular superoxide production in Peltigera canina. Lichenologist 35, 8789.CrossRefGoogle Scholar
Berjak, P. and Mycock, D.J. (2004) Calcium, with magnesium, is essential for normal seedling development from partially dehydrated recalcitrant axes: a study on Trichilia dregeana Sond. Seed Science Research 14, 217231.CrossRefGoogle Scholar
Berjak, P. and Pammenter, N.W. (2001) Seed recalcitrance – current perspectives. South African Journal of Botany 67, 7989.CrossRefGoogle Scholar
Berjak, P. and Pammenter, N.W. (2004) Recalcitrant seeds. in Benech-Arnold, R.L.;, Sánchez, R.A. (Eds) Seed physiology: Applications to agriculture. New York, Haworth Press (in press).Google Scholar
Berjak, P., Farrant, J.M. and Pammenter, N.W. (1989) The basis of recalcitrant seed behaviour. pp 89108in, Taylorson, R.B. (Ed.) Recent advances in the development and germination of seeds. New York, Plenum Press.CrossRefGoogle Scholar
Berjak, P., Mycock, D.J., Wesley-Smith, J., Dumet, D. and Watt, M.P. (1996) Strategies for in vitro conservation of hydrated germplasm. pp. 1952in Normah, M.N.;, Narimah, M.K.;, Clyde, M.M. (Eds) conservation of plant genetic resources. Kuala LumpurPercetakan Watan Sdn.Bhd.Google Scholar
Berjak, P., Walker, M., Watt, M.P. and Mycock, D.J. (1999) Experimental parameters underlying failure or success in plant germplasm cryopreservation: a case study on zygotic axes of Quercus robur L. CryoLetters 20, 251262.Google Scholar
Calistru, C., McLean, M., Pammenter, N.W. and Berjak, P. (2000) The effects of mycofloral infection on the viability and ultrastructure of wet-stored recalcitrant seeds of Avicennia marina (Forssk.) Vierh. Seed Science Research 10, 341353.CrossRefGoogle Scholar
Dua, V.K., Nagpal, B.N. and Sharma, V.P. (1995) Repellent action of neem cream against mosquitoes. Indian Journal of Malariology 32, 4753.Google ScholarPubMed
Engelmann, F. (1997) In vitro conservation methods. pp. 119147in Callow, J.A.;, Ford-Lloyd, B.V.D. (Eds) Biotechnology and plant genetic resources. Chichester, John Wiley and Sons.Google Scholar
Engelmann, F. (1999) Alternative methods for the storage of recalcitrant seeds–an update. pp. 159170in Marzalina, M.;, Khoo, K.C.;, Tsan, F.Y.;, Krishnapillay, B. (Eds) Recalcitrant seeds: Proceedings of the IUFRO seed symposium, 1998. Kuala Lumpur, Malaysia FRIM.Google Scholar
Finch-Savage, W.E. (1992) Embryo water status and survival in the recalcitrant species Quercus robur L.: evidence for a critical moisture content. Journal of Experimental Botany 43, 663669.CrossRefGoogle Scholar
Ford-Lloyd, B.V. and Jackson, M.T. (1991) Biotechnology and methods of conservation of plant genetic resources. Journal of Biotechnology 17, 247256.CrossRefGoogle Scholar
Hendry, G.A.F. (1993) Oxygen free radical processes and seed longevity. Seed Science Research 3, 141153.CrossRefGoogle Scholar
Hong, T.D. and Ellis, R.H. (1996) A protocol to determine seed storage behaviour. IPGRI Technical Bulletin No. 1. Rome, International Plant Genetic Resources Institute.Google Scholar
Kioko, J.I. (2003) Aspects of post-harvest seed physiology and cryopreservation of three medicinal plants indigenous to Kenya and South Africa. PhD Thesis, University of Natal, Durban, South Africa.Google Scholar
Kioko, J., Berjak, P., Pammenter, N.W., Watt, P. and Wesley-Smith, J. (1998) Desiccation and cryopreservation of embryonic axes of Trichilia dregeana Sond. CryoLetters 19, 511.Google Scholar
Krogstrup, P., Baldursson, S. and Norgood, J.V. (1992) Ex situ conservation by use of tissue culture. Opera Botanica 113, 4953.Google Scholar
Leprince, O., Deltour, R., Thorpe, P.C., Atherton, N.M. and Hendry, G.A.F. (1990) The role of free radicals and radical processing systems in loss of desiccation tolerance in germinating maize (Zea mays L.). New Phytologist 116, 573580.CrossRefGoogle Scholar
Liang, Y. and Sun, W.Q. (2000) Desiccation tolerance of recalcitrant Theobroma cacao embryonic axes – the optimal drying rate and its physiological basis. Journal of Experimental Botany 51, 19111919.CrossRefGoogle ScholarPubMed
Lloyd, D.G. and McCown, B.H. (1981) Commercially feasible micropropagation of mountain laurel (Kalmia latifolia) by use of shoot-tip culture. International Plant Propagators' Society: Combined Proceedings 30, 421427.Google Scholar
Minibayeva, F., Mika, A., Lüthje, S. (2003) Extracellular peroxidases are involved in the wound-induced superoxide production by wheat roots. p. 36in Abstracts of the 4th international workshop on desiccation-tolerance and -sensitivity of seeds and vegetative plant tissues, Blouwaterbaai, South Africa.Google Scholar
Mulholland, D.A. and Taylor, D.A.H. (1980) Limonoids from the seeds of the Natal Mahogany, Trichilia dregeana. Phytochemistry 19, 24212425.CrossRefGoogle Scholar
Nagpal, B.N., Srivastava, A. and Sharma, V.P. (1996) Control of mosquito breeding using scrapings treated with neem oil. Indian Journal of Malariololgy 32, 6469.Google Scholar
Pammenter, N.W. and Berjak, P. (1999) A review of recalcitrant seed physiology in relation to desiccation-tolerance mechanisms. Seed Science Research 9, 1337.CrossRefGoogle Scholar
Pammenter, N.W., Greggains, V., Kioko, J.I., Wesley-Smith, J., Berjak, P. and Finch-Savage, W.E. (1998) Effects of differential drying rates on viability retention of Ekebergia capensis. Seed Science Research 8, 463471.CrossRefGoogle Scholar
Pammenter, N.W., Berjak, P., Wesley-Smith, J., Vander Willigen, C. (2002) Experimental aspects of drying and recovery. pp. 93110in Black, M.;, Pritchard, H.W. (Eds) Desiccation and survival in plants: Drying without dying. WallingfordCABI Publishing.CrossRefGoogle Scholar
Walters, C., Pammenter, N.W., Berjak, P. and Crane, J. (2001) Desiccation damage, accelerated ageing and respiration in desiccation tolerant and sensitive seeds. Seed Science Research 11, 135148.Google Scholar
Wesley-Smith, J., Walters, C., Pammenter, N.W. and Berjak, P. (2001) Interactions of water content, rapid (non-equilibrium) cooling to –196°C and survival of embryonic axes of Aesculus hippocastanum L. seeds. Cryobiology 42, 196206.CrossRefGoogle Scholar
Wilkins, C.P. and Dodds, J.H. (1983) The application of tissue culture techniques to plant genetic resources. pp. 259284in Withers, L.A.;, Anderson, P.G. (Eds) Plant tissue culture and its agricultural applications. London, Butterworths.Google Scholar