Articles
CRYOBANKING CASSAVA GERMPLASM AT IITA
Article number
908_56
Pages
439 – 446
Language
English
Abstract
The IITA (International Institute of Tropical Agriculture) genebank maintains over 4000 accessions of cassava (Manihot esculenta Crantz). During the past few years, over two-thirds of the collection was transferred to in vitro storage conditions.
To further rationalize in vitro conservation, cryobanking is presently under investigation.
Cryopreservation tests comparing a droplet-vitrification- with an encapsulation/dehydration-based process were performed on meristems excised from seven accessions.
Droplet vitrification was shown to be more promising in terms of meristem recovery after cryopreservation and simplicity to scale-up.
Cryopreservation via droplet vitrification was further applied to 48 accessions.
Survival was observed for most accessions (96%) when thawed within the same day as cryopreservation (direct thawing). However, this rate dropped to 75% when the cryopreservation process included temporary storage in a cryotank (delayed thawing). This suggests cryotube transfer and retrieval from the liquid nitrogen tank needs further optimization.
Our results also suggested that the longer the loading treatment, the better meristem post-cryopreservation performance.
Depending on accessions, 6 to 86% of the meristems surviving cryopreservation were able to produce a shoot.
The droplet vitrification procedure is a promising approach for cryobanking cassava.
However, further standardization of the cryopreservation process is needed before it becomes one component of cassava ex situ conservation strategy at IITA.
To further rationalize in vitro conservation, cryobanking is presently under investigation.
Cryopreservation tests comparing a droplet-vitrification- with an encapsulation/dehydration-based process were performed on meristems excised from seven accessions.
Droplet vitrification was shown to be more promising in terms of meristem recovery after cryopreservation and simplicity to scale-up.
Cryopreservation via droplet vitrification was further applied to 48 accessions.
Survival was observed for most accessions (96%) when thawed within the same day as cryopreservation (direct thawing). However, this rate dropped to 75% when the cryopreservation process included temporary storage in a cryotank (delayed thawing). This suggests cryotube transfer and retrieval from the liquid nitrogen tank needs further optimization.
Our results also suggested that the longer the loading treatment, the better meristem post-cryopreservation performance.
Depending on accessions, 6 to 86% of the meristems surviving cryopreservation were able to produce a shoot.
The droplet vitrification procedure is a promising approach for cryobanking cassava.
However, further standardization of the cryopreservation process is needed before it becomes one component of cassava ex situ conservation strategy at IITA.
Authors
D. Dumet, S. Korie, A. Adeyemi
Keywords
cryopreservation, genebanking, droplet vitrification
Online Articles (65)