A Common Heritage of Humankind

Soraya and David Bertioli, both experts in the field of peanut genomics at the University of Georgia, talk about their research and the importance of making the genetic materials available worldwide.

// Soraya, you are from Brazil and David from the UK. Tell us how you ended up working on peanuts in the US at the University of Georgia?

That’s right. David and I met when I went to England to do a PhD. He had just finished his DPhil from Oxford and was working as a pos doc at Rothamsted Experimental Station, where I did the practical part of my thesis. Although we come from very different backgrounds, countries, etc, we had in common the desire to make agriculture more efficient and environmentally friendly. We moved to Brazil after I finished the PhD. I went to work at Embrapa and he at the University of Brasilia. The wild peanut seed bank of Embrapa was an amazing resource, well curated, with lots of wonderful information, from a very important crop, yet underutilized. We saw an opportunity to make a difference for the crop by studying and utilizing the wild species. Our story with the US happened when the Peanut Genome Initiative was at full speed – it used DNA from the populations we had created in Brazil with A and B genome species, using the peanut progenitors. As we were so involved with the genome project, our presence in the USA made sense. Once we were there, the University of Georgia recognized the importance of wild species for the peanut crop (Georgia produces over 50 percent of the total US peanuts) and offered us both permanent positions. It was a difficult decision to leave our jobs in Brazil, but we have been very happy at UGA. It offers excellent structure and support to the program. You can see some glimpses of it at https://wildpeanutlab.uga.edu/.

// When was your first contact with wild peanut species and why did you decide to dedicate your life to investigating this topic? Did you foresee the impact that your investigations would have on peanut breeding?

The curator of the wild germplasm bank in Embrapa, Brasilia, Dr Jose Valls, was a very inspiring influence. His enthusiasm about the collections, the structure, the different species, it was really contagious! We started to learn about wild species that had strong resistances, but that were also very difficult to cross with the cultivated peanut. We learned about the weird genetics, and the more we learned the more we became fascinated with the genus. Several colleagues at Embrapa joined this quest and, as a group, we started to see the potential of this project. While we had to deal with basic science (genetics, genomics, plant pathology, functional genomics), we always had the practical benefits as the end goal. Embrapa always encouraged us to have collaborations abroad and this helped the knowledge to be shared.

// Let’s get to the technical stuff, could you describe what is so special about wild species?

Wild crop relatives are known to harbor alleles that have been lost in the cultigen, but that can be retrieved by breeding. In the case of peanut, the wilds have a different number of chromosomes (20) than that of the cultivated species (40). This poses significant challenges; it hampered the whole introgression process for years. We have now created a pipeline that allows a constant flow of alleles to peanut. We can now transfer resistances to pests and diseases, yield stability under different environments, drought “tolerance” (in specific areas), productivity, seed size, and many other traits. Now the bottleneck is the capacity to test for these traits.

// How easy is it to take the “good features” of wild species and transfer them to cultivated peanuts? And how long does it take?

While it is not easy, now it is possible and routine. One of the hardest parts is to obtain the allotetraploid, which is a hybrid between wild species which is compatible (crossable) with peanut. This can take anything from one to several years. It depends on the compatibility of the species, the stability of the diploid hybrid, how easy the hybrid duplicates, the stability of the allotetraploid, the capacity of the tetraploid to produce seed and, finally, the compatibility of the allotriploid with peanut (if it produces fertile progeny). We are making these allotetraploids in a structured way, to incorporate the widest possible genetic diversity in a reasonable number of hybrids. We are depositing these allotetraploid hybrids in seed banks so they can be used in any breeding program as a donor of desirable traits.

// Can you briefly mention the resistance genes that are already available for peanut breeders, and what do you expect may be available in the coming ten years?

The first peanut wild resistances were to root-knot nematode (Meloidogyne arenaria), this work was done at Texas A&M University, using the species Arachis cardenasii. Then, resistance to late leaf spot (Northopassalora personata), which was done at North Carolina State University. Recently, a significant release was Sempre Verde in Brazil, this cultivar, which has resistances from Arachis cardenasii, does not need to be sprayed a single time during the growing season! (In contrast to 7-9 times which has been standard up to now.)

Other resistances are to: early leaf spot, rust, TSWV, Ralstonia solanacearum (in China), GRD (in Africa), stem rot and others. Soon more cultivars will combine these resistances and this will greatly reduce chemical applications.

// In one of your published articles, you addressed difficulties in collecting wild species and sharing them across countries. Could you please explain this? Did anything change with respect to the past?

The Convention on Biological Diversity was implemented in 1993. Before that, collections of wild plants and seeds, and exchanges, were done with few restrictions and indeed were encouraged by a system which prioritized the preservation of germplasm in seed banks. There are numerous examples of large benefits of seed exchange to mankind over the centuries. After the convention was implemented, national laws and regulations, regional agreements and various other layers of bureaucracy have impeded and almost stopped most collections and almost all seed exchange. This poses an enormous threat for food security, to science and local costumes. This is a very undesirable set of changes which damages food security. In the meantime, wild populations are being lost continuously with human expansion into wild areas.

// Are the countries that restrict wild material exchange getting any benefits from these decisions? We hear every day that human activities are impacting biodiversity. Do you see the risks of losing some of these wild materials? Shouldn´t it be safer to have them in seed banks rather than lying in the field unprotected?

Although the intentions of these conventions are good, in over 30 years almost zero benefits have materialized to any country or land owner. The most recent analysis showed that as of 2019 there was only a single payment into Plant Treaty’s Benefit Sharing Fund as a result of its mandatory monetary benefit-sharing conditions. As human population increases, cities and agricultural land expand, natural landscapes disappear and with them, the precious wild species. If it was easier to make collections, seeds could be collected and stored in germplasm banks. Additionally, they would be duplicated and backed up in various other banks, but for that to happen (like it used to routinely before the convention), less stringent legislations would need to be put in place.

// I believe this debate leads to the question regarding who the owner of biodiversity is. In your opinion, should wild species be available for the whole world? Should they be considered humankind’s property rather than that of nations?

This is the core of the question! Wild species used to be considered the “common heritage of humankind.” Unfortunately, some private interests moved to patent genes and the use of wild species. The convention was a reaction to this, but it had massive unintended consequences. Instead of preventing illegitimate private ownership, it created a “hyper-ownership,” where every wild species is governed by multiple laws and conventions. The end result is that it’s much easier to get permission to completely destroy natural habitats (to expand agriculture, infrastructure or housing) than it is to get permission to collect seed from wild plants. What’s needed is to return to the “common heritage” model with added safeguards against illegitimate private ownership.