So it seems that everybody just duplicates everything… As Sandy wrote from Étape Eggplant in Montfavet, our last week’s focus on eggplants has revealed that duplicates are an issues not only in our database but in any collections such as world’s seed bank collections. So what is it with duplicates that make them an issue?
My role last week included gathering data on eggplant wild relatives, including both records of their natural distribution and currently available germplasm collections in seed banks. The idea of the gap analysis is to see whether eggplant crop wild relative (CWR) diversity is conserved in seed bank collections, and to identify where new collections should be made. It is a fascinating job – not only does it surprise you that such basic questions have not been looked into before, but the job also turns out to be more complex than you would expect at first.
It is easy to assume we (or somebody high up in one of the United Nations offices) know what is currently conserved in seed bank collections around the world. Seed banks are, after all, cornerstones of food security, banking seeds for the future if something would to happen. So somebody is counting what is being conserved across the globe, right? The answer is not that simple. For the ten or so most important food crops, specialised research institutes have been established to secure conservation and management of these important crops. For others, such as eggplant, the story is different.
World’s major seed banks, or genebanks as they are often called, all have their focus groups or focal areas. The bulk of these genebanks belong to CGIAR, the Consultative Group on International Agricultural Research, which is an informal network of 16 international agricultural research centres. Together, these 16 institutions manage c. 600,000 agricultural seed samples – that is quite a lot! On top of these international giants, there are national or more regional genebanks, such as the United States Department of Agriculture’s National Plant Germplasm Service (NPGS), and the Dutch national seed bank at Wageningen University, the Centre for Genetic Resources, the Netherlands (CGR). Despite their different sizes and slightly different mandates, these seed banks all share the aim of preserving crop diversity.
Picture of the Svalbard Global Seed Vault: located in Spitsbergen, an island north of Norway, the Vault is storing seeds for the future.
The idea behind seed banking is to conserved diversity for future, short or long term, needs. These needs change through time. Currently, focus is being given to breeding crops to prepare them for the changing climates, as well as increased disease and environmental stress resistance. What needs to be analysed, however, is whether the currently conserved accessions in seed banks have potential in breeding efforts for these priority traits. Gap analysis, such as our project on eggplants and their wild relatives, have been developed to answer these questions and play an important role in understanding the potential of currently banked accessions for these priority breeding targets.
How does this all relate to duplications? Well from my short experience in this field, I have learnt that many of our global seed collections are actually duplicates. I have now worked on both tomato and eggplant CWR collections, downloading germplasm data from individual genebanks and then merging them to a single file to prepare them for the gap analysis. Seed banks exchange material, not only for diplomatic reasons but for the very important reason of securing their collections. Such duplications are called safety duplications, and are mandatory for large genebanks. This assures that if something would to happen due to political (wars do happen unfortunately) or environmental reasons (e.g. earthquakes), not all eggs were put in one basket.
What does this mean for food security? Well firstly it is great that if something would to happen, duplicates are safe somewhere around the world. But the other side of the coin is that although seemingly looking large at first sight, the actual number of seed collections conserved around the world is not that big after all. Conserving and preserving seeds in long term storage is costly, and this reduces the amount that can be kept in the banks.
My job this week continues to focus on pruning some of these duplicates out. For the sake of our gap analysis, we want to make sure we represent the global collections realistically. Some argue that duplicates can be viewed as unique collections because seeds have to be regenerated at regular time intervals and this process leads to slight differences between the duplicate collections. From the point of view of unique genetic resources that could be used for adapting our crops to climate change, we need truly unique collections that represent extreme environmental adaptations. Complex traits such as drought resistance or salt tolerance do not vary between duplicates – they evolve over hundreds if not thousands or even millions of years.