A team of scientists carefully tends a cornucopia of grains and vegetables each year that will never be eaten or sold. 

canada's Seed Hoarders

Instead, the seeds they grow in fields, greenhouses and growth chambers are harvested and housed like precious gems in a fortress behind two sets of security doors, windows made from bullet-proof glass and boulders outside to prevent someone using their vehicle to ram their way inside.

The vaults are equipped with a waterless fire protection system and back-up generators to ensure a power outage won’t interfere with the temperature-controlled environment.

Diederichsen is a banker of sorts in his role as curator of the Plant Gene Resources of Canada (PGRC) facility, which is part of the Agriculture and Agri-Food Canada (AAFC) Saskatoon Research and Development Centre.

The facility serves as the gatekeeper of Canadian field crop genetic diversity. It’s up to Diederichsen and the PGRC team to manage deposits and withdrawals from this vital seed bank, all the while preserving the viability of inventories kept in storage.

At the heart of the seed vault is a specialized data management system that allows PGRC to be accessible globally.

Number of Samples currently in the vault

“We have a database manager looking after our gene bank information system,” he says. “It is very important to have a system that can communicate with the whole world. No matter where they are, people can go on-line to inspect our seed collection and make requests.” Along with information available on the physical server they are in the process of moving their data to the cloud.  


“A big part of the PGRC program also involves restocking the inventory,” says Diederichsen. “Most years we have about 5,000 accessions (withdrawals) from the seed bank and that has to be replaced.”  


All seeds in the collection are available to plant breeders, researchers and educators in any part of the world looking to older relatives of varieties for traits that might help improve or protect the crops grown today. 


Restocking inventory requires an active seeding program on the AAFC land to plant varieties in the field, or if warranted, in greenhouses to produce seed necessary to sustain the collection. 


“With so many species it is very challenging to manage the seed reproduction,” says Diederichsen. “Whether they are open pollinated or self-pollinating types we need to be watchful and remove any off types, also ensure plants are homogenous, and always carefully observe to ensure pure seed quality.” 


But it’s a role he’s taken pride in fulfilling ever since he arrived on the scene nearly a quarter century ago. 


Born and raised in Germany, Diederichsen obtained PhD in plant breeding/genetic resources and worked with the German National Gene Bank before successfully applying to be curator of the PGRC in Saskatoon in 1998.

In 2010-11 he took a leave of absence from the PGRC to work with the Nordic Genetic Resource Centre in Sweden. That centre looks after plant genetic material for five countries including Finland, Sweden, Denmark, Norway and Iceland. 


The centre is also responsible for the operation of the Svalbard Global Seed Vault in Norway. Just over a year later, he returned to the PGRC in Saskatoon.


Since it was created, the 50-year-old PGRC, has quietly preserved the genetics of Canadian field crops grown over the past 120 years. Its first few years were spent gathering up samples of earlier crop crop cultivars and landraces species that had been deregistered or were no longer in commercial production. These were donated by plant breeders and researchers who had maintained genetic material in their own working collections.  


But the PGRC is no museum focused on the historical significance of past achievements. Far from it. 


These genetics are a vital source of diversified plant genetic material Canadian researchers and plant breeders rely on to develop crops for the future.  


“The role of the gene bank is three-fold,” says Diederichsen. “First, is to preserve the plant genetics of cultivated crops of relevance to Canada and to distribute materials we have in the collection to plant breeders, researchers and educators. Second is to generate and make information about the germ plasm or seed available to plant breeders and researchers and third is to collaborate with others nationally and internationally who are also involved in the conservation of this genetic diversity.



A conference held by the United Nations Food and Agricultural Organization (FAO) in 1967 urged all member countries to establish gene banks for important agriculture crops. 


In Canada, that lead to the construction and then opening in 1970 of the first Plant Gene Resources of Canada seed vault at the AAFC  Experimental Farm in Ottawa. 


The collection was housed there for nearly 30 years until a new facility was built as part of the AAFC Saskatoon Research and Development Centre in 1998. 


As with all AAFC research centres in recent years, public access is controlled. Diederichsen says visitors are welcome although people can’t just walk in off the street to enter the PGRC wing.  “Visitors need to come to the main reception desk of the research centre first, then someone from our office will meet them and escort to our area,” he says.  


PGRC has seeds that can survive 150 years in the freezer.

87,000 samples sent to 67 countries.

The PGRC collection is stored in two main vaults designed for both short and long-term storage. The seed vaults themselves are rooms that are about 10 metres by eight metres with ceilings at 2. 5 metres high. One vault is kept at plus 4 C and held at a low 20 per cent relative air humidity. Under these cool, dry conditions seeds can remain viable for several years, the medium term. The other vault, is kept at minus -20 C. Under those conditions, good quality seed in sealed envelopes can remain viable for more than 150 years.  Each vault is outfitted with floor to ceiling moveable racks that hold trays of seed envelopes. 

The PGRC gene bank aims to have a sample of about 10,000 seeds of any particular crop in storage. With wheat for example, that represents about 300 to 400 grams of seed.

Each seed batch is divided into three types of storage envelopes. Part of the sample is put into paper envelopes, which are the “working collection,” says Diederichsen. Those envelopes can be opened, seeds removed and sent to a plant breeder or researcher, and seeds in that envelope can also be tested for viability. Those seed envelopes are kept in the cool storage vault.

The second seed sample is placed into laminated foil envelopes and sealed for long-term storage in the minus -20C vault.  The third is a smaller seed sample sealed in an envelope that is sent to the World Seed Vault in Norway, providing a back-up sample, in the event anything might happen to spoil the samples at PGRC in Saskatoon.

The PGRC receives about 120 to 130 requests per year for seed samples. 


“The request could be for one seed sample, or five samples or 5,000 samples,” says Diederichsen. 


In 2019, for example, they accommodated requests for some 25,000 seed samples. “Part of that is due to researchers and plant breeders who are now screening such large amounts of plant materials,” he says. Since 2002, the PGRC has shipped out more than 70,000 seed samples to clients in 65 countries. 


Along with providing storage for these plant genetic resources, PGRC closely monitors the “working collection.” As seed is sent out to breeders and researchers the inventory needs to be updated, replaced as needed and the collection is also monitored to determine seed viability.


A directory of the full PGRC collection is available on line and access to genetic material is free to any bonafide researcher, plant breeder or educator looking for certain species or varieties provided any product of the research or breeding program remains available to the public.

 “If a breeder uses material from PGRC to develop a new cultivar with Plant Breeder Rights protection then that material can be used by any other breeder or researcher with no fee obligations along as it remains freely accessible,” says Diederichsen. “However if someone uses material from the gene bank to develop a cultivar and they maintain exclusive rights or essentially hold a patent on the new variety then they must pay a fee to what’s known as the Benefit Sharing Fund of the International Treaty of Plant Genetic Resources For Food and Agriculture.” That fund is administered by a global committee which makes decisions on crop diversity conservation that benefit farmers in developing countries.


Diederichsen says as the PGRC collection has grown over the years to the point where it has outgrown the dedicated vault space. “There are always some day-to-day challenges, but probably one of the most important right now is the need for more space,” he says. 


“We are in an overflow situation, particularly with our long-term storage facility. Right now there is no room for about 20 per cent of the collection that should be in long-term storage.” While the overflow seed envelopes are safe in the cool storage vault, plans have been made to expand the cold storage vault, however no decision has been made on timing of the renovation project.


Contributor: Lee Hart