| EJB Electronic Journal of Biotechnology
ISSN: 0717-3458 |
| © 2000 by Universidad
Católica de Valparaíso -- Chile |
Facilitating safe
movement of yam Dioscorea spp. germplasm. Current knowledge, facilities,
cost, and international collaboration
Bernard Malaurie*
GeneTrop - Génétique et Amélioration
des Plantes - Centre ORSTOM
BP. 5045 -F. 34032 - Montpellier Cedex 1
France
E-mail: Bernard.Malaurie@mpl.orstom.fr
Mustapha Bousalem
Laboratoire de Phytovirologie
des Régions Chaudes (LPRC) - CIRAD
BP. 5035 -F. 34032 - Montpellier Cedex 1
France
Jean Dubern
Laboratoire de Phytovirologie
des Régions Chaudes (LPRC) - CIRAD
BP. 5035 -F. 34032 - Montpellier Cedex 1
France
Julien Berthaud
GeneTrop - Génétique et Amélioration
des Plantes - Centre ORSTOM
BP. 5045 -F. 34032 - Montpellier Cedex 1
France
*Corresponding author
Keywords: cryopreservation,
disease-free conditioning material, indexing, introduction and
cultivation into greenhouse, introduction in vitro, micropropagation,
operation and cost needed for germplasm transfer, safe germplasm
exchange, sanitation, transfer germplasm cost
Yam, as a vegetatively
propagated crop, is severely affected by an accumulation of pathogens
(viruses, anthracnose, nematodes,.). These pathogens are responsible
of great economical impact. Measures have to be taken for a safe movement
of yam. Facilities and cost required to resolve these problems are presented
here.
|
Heavy
constraint of quarantine measures
Measures
Only disease-free
material should be transferred. If non aseptic material was used
for transfer a heavy constraint of quarantine measures have to
be done. Transfer of yam germplasm should be done from pathogen-tested
material maintained in aseptic conditions (microtubers, microcuttings,
microplantlets, encapsulated apices). In vitro technique allows
the production of plants free of all diseases, except from viruses.
Production of virus-free material requires indexing, and when
needed sanitation. Indexing should be run for all known viruses.
Sanitation should be effective and simple.
|
Total
Cost of Operations for the Transfer of 100 Genotypes per Year
| |
|
|
Total cost
(FF HT)
|
|
Greenhouse
|
Introduction into greenhouse
|
|
|
| |
Cultivation in greenhouse for indexing
|
|
|
| |
Hardening and acclimatization
|
TOTAL
|
28000
|
|
Indexing
|
Indexing
(ELISA, rT/PCR.)
|
|
12000
|
|
In vitro culture
|
Introduction
in vitro (cuttings,
seeds)
|
|
8500
|
| |
Sanitation
(meristem culture, Chemical & thermal treatment)
|
|
35000
|
| |
Micropropagation
|
|
10000
|
| |
Cryopreservation
|
|
10000
|
| |
TOTAL
|
|
103500
|
|
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Conclusion
For an integrated
international safe movement of yam germplasm, we need to develop
a chain of facilities with quarantine, indexing, sanitation and
in vitro conservation. All of the elements of this chain, fully
efficient, have to be linked, in a unique location or distributed
over several locations, and be cost efficient.
|
Type
of yam material available for a safe transfer
|
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