genetic resources

Shin-Ichi Yamamoto, Genetic Resources Center, National Agriculture and Food Research Organization (NARO)

The National Agriculture and Food Research Organization (NARO) conducts Genebank Project for collecting, conserving, evaluating, multiplying and distributing plants (228,198 accessions), microorganisms (35,407 acc.), animals (1,971 acc.) and DNA materials (394,440 clones) related to agriculture since 1985. The Genetic Resources Center, NARO (NGRC) coordinates this activity in collaboration with a network of institutes (so-called sub-banks) throughout Japan. In the plant section of the project, orthodox seeds are conserved in a seed storage at -18 ℃ for long term and at -1 ℃ for medium term, respectively. Approximately 30,000 accessions of plant genetic resources are clonal crops. They are basically conserved in fields or greenhouses of sub-banks and very useful for immediate use. However, the construction of cryobank will contribute significantly to the cost-effective long term preservation of vegetatively propagated crops in a stable manner in safe and disease-free conditions as safe backup. In NGRC, winter dormant buds of 1,283 mulberry accessions have been cryopreserved. But this method cannot be available for the crops which do not form dormant buds. Although existing cryopreservation methods such as vitrification and droplet methods for in vitro shoots can be applicable for those crops, more systematical protocol is desirable for facilitating cryobank for them. Therefore, we developed efficient and simple cryopreservation procedures, V and D cryo-plate procedure using small hard aluminum plates with micro-wells. These methods have many advantages such as simple handling, high regrowth rate, very high cooling and warming rate, easy learning and so on. We already started to preserve clonal plant genetic resources such as potato (310 acc.), mat rush (181 acc.) and so on by these methods in NGRC liquid nitrogen tanks. We plan to increase accessions stored systematically and establish a cryobank project in Japan.

Date Recorded: 
Tuesday, July 23, 2019

Bart Panis, Bioversity International, Belgium

More than 800 million people are undernourished and 200 million children under five years of age are underweight. Moreover, the world’s population is expected to reach 10,500 million by 2050. Reliable and sustainable improvements in yield will thus be needed to meet the demands of this growing population. The availability of the largest possible crop diversity is central to food security. Crop collections encompass seed propagated as well as vegetatively propagated crops. Seed is classically stored at -20°C (and sometimes cryopreserved) while vegetatively propagated crops are maintained in the field, stored as in vitro collection under reduced growth conditions or through cryopreservation. Cryopreservation plays an essential role in the safe conservation of plant genetic resources of vegetatively propagated crops like bananas, cassava, potato, yams and sweet potato. Cryopreservation research on these crops already started in the 80ties but it was only with the development of vitrification protocols and more recently with the use of droplet vitrification that a significant portion of such collections are now stored in liquid nitrogen. The droplet vitrification protocol was established because it combines the application of highly concentrated vitrification solutions (often PVS2) with ultra-fast freezing and thawing rates both leading to a lower chance of lethal ice crystal formation. Currently, over 10,000 accessions starting from in vitro cultures are safely preserved for the long term through cryopreservation. More than 80% of these belong to 5 crops; potato, cassava, bananas, mulberry and garlic. Other important cryopreserved collections representing thousands of accessions are those of dormant apple buds. One of the recommendations of an expert group to apply cryopreservation to a wider diversity of vegetatively propagated crops was to establish a collaborative effort among researchers and genebanks that is focused on the specific technical and practical issues.

Date Recorded: 
Monday, July 22, 2019