source photography https://www.consoglobe.com/sem…
2021. Article written by Hélène Pascal, M2BEE student.
Genetic diversity is crucial for species to adapt to their environment. However, the large seed companies have greatly reduced the diversity of cultivated plants. What are the initiatives to fight against this loss?
Genetic biodiversity, essential for the adaptation of species
Usually when we talk about biodiversity we mainly include the diversity of species. However, since the international conference in Rio in 1992, this notion has taken on new dimensions, and two other aspects are included: the diversity of ecosystems (the environments in which live), and probably the least known, genetic diversity. [1]. What is it for and therefore why is it important to preserve it, one might ask? The most important aspect is adaptation. The diversity of genes allows species to adapt, in particular to their environment. This is how natural selection can operate: individuals who are best suited from the point of view of their behavior or their physiology thanks to their genes are at an advantage. Animal and plant species, whether wild or cultivated, which have lost their diversity are thus in danger. They will no longer be able to adapt to the changes to come. However, climate change suggests many changes. So lGenetic diversity is a stake for the food future of humanity when we speak of cultivated species.
How man has used genetic diversity …
Man has always used the genetic diversity at his disposal to improve an animal or plant species. The best individuals on one or more criteria (quality of wool for sheep, quantity of milk for cows, yield for wheat, etc.) are crossed with each other, in order to improve the value of the offspring compared to that of the parents [2]. If some individuals are better than others, it is by definition that a diversity, in this case genetic, is present. This way of selecting species is very efficient. Wheat, for example, has seen its yields tripled in 30 years, although selection has not been the only factor in this progress.[3].
… To finally reduce it drastically?
However, this process of selection and improvement of species, when it relies almost exclusively on large multinationals as is currently the case, leads in the medium and long term to a loss of biodiversity from a genetic point of view. . In fact, the selection made by these companies has one and the same overall objective, yield; sometimes with secondary objectives such as improving resistance to disease. Thus, a large number of unnecessary genes, even deleterious for these purposes, are not selected, ending up being lost over the generations. This loss of diversity is all the more accelerated as agriculture is more and more standardized. This standardization has an advantage for seed companies: if the irrigation conditions, pesticides and fertilizers are the same in Hungary or France, a variety will perform equally well in these two countries. These large companies are aware of the problem linked to the loss of genetic biodiversity, by dint of reducing the genetic diversity that they use, no more source of progress for yield is possible, for lack of variability. So they introduce some new genes by crossing with old varieties or exotic varieties. But these introductions are very controlled, and all the discomforts which are not useful to them are again eliminated.
These overpowered companies have conquered a very large part of the seed market globally, whether in developed or developing countries. Today 70% of the global seed market is controlled by 10 companies [4]. In Thailand, the number of cultivated rice varieties has historically fallen from 16,000 to 37 [5]. When peasants abandon their ancestral practices to engage in intensive agriculture, they have little choice but to use seeds selected by multinationals. They thus lose the genetic diversity which they have inherited, and become dependent on an agrochemical system. Thus according to the Food and Agriculture Organization of the United Nations (FAO), agricultural biodiversity has been reduced by 75 % between 1900 and 2000 [4]. Since then, the trend has not reversed. This dependence on commercial seeds also raises the question of food sovereignty.
This picture is rather gloomy. Fortunately, initiatives have emerged to preserve the heritage represented by the genetic diversity of cultivated plants.
International awareness
The International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) is an agreement adopted in November 2001, under the aegis of the FAO. Its aim is “the conservation and sustainable use of plant genetic resources for food and agriculture, as well as the equitable sharing of the benefits deriving from their use”. It relates more particularly to 64 species of crops and fodder. The treaty recognizes the contribution of farmers and local communities to the conservation and development of seed genetic resources. The Nagoya Protocol on Access and Benefit-sharing, entered into force in 2014, should work hand in hand with ITRPAA. Adopted within the framework of the Convention on Biological Diversity, its objective is “the fair and equitable sharing of the advantages arising from the use of genetic resources, in particular through satisfactory access to genetic resources”. Its primary goal is therefore not to preserve these resources, but it provides, among other things, to improve access to them, and to regulate their use for commercial purposes in order to avoid the plundering of countries rich in biodiversity.
Seed banks and citizen movements
In the world, many seed banks exist: more than 17,000 have been created throughout the world. The purpose of these structures: to conserve seed varieties (traditional or not). Thus, it will be possible to use them in case of need such as climate change or the appearance of diseases. The most spectacular initiative is in the Svalbard archipelago, in Norway. In 2006 a consortium decided to build a giant safe, also called Noah’s Ark plant. The goal of this initiative? Protect the food heritage of our planet. For this, crop seeds from all over the world are stored there, with the aim of accommodating as much diversity as possible. In 2020, the mark of one million stored varieties has been exceeded [6]. This giant bunker was dug 120 meters deep in a mountain. It must withstand a nuclear attack, a plane crash or even a rise in sea level. It is refrigerated at -18 ° C, the optimum temperature for the conservation of seeds, even if they are renewed. regularly. In 2015, it was used to replenish the seed bank of the city of Aleppo, destroyed by the war. It is in this type of situation, that is, in the event of a loss of a local seed bank, that this facility is most likely to be used. But it cannot be ruled out that it is a solution in the event of a global catastrophe (Anne-Laure Frémont, le Figaro science)
Finally, many movements have been created around peasant seeds. The latter are selected, and multiplied by the farmers themselves, in opposition to certified seeds, sold by seed companies. [7]. Adapted to each terroir, these seeds carry great genetic diversity. They also help ensure food sovereignty. In France, we can cite the Peasant Seeds Network, or Via Campesina at the global level.
Modern breeding, with all the financial and human resources that it implies, has made it possible to greatly increase crop yields. Faced with the food challenges linked to demography and global warming, a new model may therefore have to be invented, somewhere between ultra-selected seeds in the hands of a few multinationals and peasant seeds.
Mini glossary
Gene: a sequence of DNA and inheritable, the expression of which affects the characters of an organism.
Phytogenetics: which refers to the genetic material of plants
Sources and additional information
[1] The three levels of biodiversity. Laura Fdez Roldán. March 25, 2021
https://www.projetecolo.com/les-3-niveaux-de-la-biodiversite-13.html
[2] The management of seeds and cultivated diversity. The granaries of plenty. August 14, 2020
https://resiliencealimentaire.org/la-gestion-des-semences-et-de-la-diversite-cultivee/
[3] A race for performance over a ten-year period. Mathilde Carpentier
[4] The dangerous concentration of the market. Public eye.
https://www.publiceye.ch/fr/thematiques/semences/concentration
[5] Biodiversity and agro-ecology – reducing risk in food systems? Phil Tuite
https://www.fao.org/fsnforum/cfs-hlpe/comment/3901
[6] A million seeds preserved in an underground “Noah’s Ark” in the Arctic. Anne-Laure Frémont, the Figaro science
[7] Definition of peasant seeds, dictionary of Agroecology. Marianne Dubrulle, Elodie Pimouguet and Laurent Hazard
https://dicoagroecologie.fr/encyclopedie/semences-paysannes/
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