Dangerous Genetic Erosion
Dangerous Genetic Erosion
Take action: this must be the watchword that must involve the governments of all the countries of the world.
We are talking about Genetic Erosion. For the sake of information, let’s see what we mean by Genetic Erosion. This term refers to the loss of natural genetic diversity, due to the destruction of territories such as tropical rain forests (where half of the animal and plant species of the earth live, many of which have not yet been studied) and the industrialization of agricultural practices.
According to some estimates of researchers from all over the world it is estimated that this, for the middle of the next century, is around 25% loss of plant species on the planet (due to deforestation, monoculture practices and water control , superpasculation and urbanization). Furthermore, the integration of agricultural markets, the industrialization of agriculture and the use of high-yielding seeds have led to the use of an extremely limited number of plant varieties with consequent progressive loss of most of the genetic varieties characteristic of the various geographical situations.
The ” green revolution ” operated in countries such as India, Indonesia and China, where food needs were the primary problem, made it possible to partially solve this problem. Now, however, Nature is presenting the bill: the price paid in terms of genetic erosion is very high: only high-yielding varieties have been cultivated, and all the others, cultivated for millennia, have been abandoned and then extinguished. The extinction of all these natural varieties has a negative impact not only from a naturalistic point of view but also from the application one.
High-yielding seeds are produced using biotechnology techniques that allow the in vitro preparation of plants in which the “responsible” genes of certain characteristics considered useful are inserted. But genes can not ” invent ” nor is it easy to reconstruct them if they have been lost with the extinction of certain varieties. Only those present in the currently existing natural varieties can be picked up and used, which have come to us as a result of natural selection. Very important in this sense are the varieties that show resistance to diseases or parasites. The use of high-yielding seeds, with the consequent genetic uniformity introduced in agriculture, has however made all crops vulnerable to the same agents.
Fortunately, in some parts of the world, the less industrialized ones, the indigenous plant varieties are still cultivated; these pockets of traditional agriculture serve as “biodiversity reservoirs” for the many different genes found in wild stocks. The rediscovery and protection of these strains has become essential nowadays: their vigor and their genetic diversity are a guarantee of our future food supply and allow us to continue to have available genetic characteristics that may be necessary in the future.
Thus, after the “Green Revolution” and its nefarious consequences, which we will unfortunately only understand in the coming years, numerous centers have existed in the world for the conservation and improvement of these plant varieties: some centers are real seed banks of the major edible species (National Seed Storage Laboratory of Colorado), others are more specialized centers such as the International Center for the Improvement of Corn and Wheat in El Batan, Mexico; the International Rice Research Institute of Los Banos, in the Philippines, or the International Potato Center in Huancayo, Peru.
In Italy the most important ” seed bank ” is located in Bari, at the Germoplasm Institute, one of the most important in the world for wheat and peas. All these centers form a network of vital importance for the conservation of genetic diversity for plants of agricultural interest.
Returning to data on genetic erosion, this phenomenon has manifested itself, only in a century, with a loss of 75% of biodiversity.
According to the FAO, 12.5% of the plants (270 thousand species present in nature of which 20 thousand edible and 7 thousand cultivated) could be canceled within a few years.
We see some data referring to the largest countries, where the seriousness of the data is indisputable: among these India (1,350 species out of 16,000) and Brazil (1,300 out of 56,000) are the nations most affected by genetic erosion. But even Italy is not immune to the problem. In our country there are 300 species at risk on a total of 5,600 and is, unfortunately, a figure destined to increase.
To be clear, for example, some varieties of spelled, tomatoes and even some types of polenta corn that our grandparents used to risk disappearing.
The problem of protecting plant species is not only scientific and technical, but above all cultural and therefore political. Despite the manifest seriousness of the data, there are many, unfortunately, the countries that completely ignore it.
Now, to better understand why genetic variability is fundamental and, above all, to cultivate in conditions of genetic variability, we underline that genetic variability is the one that allows to face adversity (for example, new pathogenic germs) and changes of any kind, including those climate – in short, the biodiversity that is essential to maintain and protect.
An example (among many) striking manifested in Ceylon.
The colonies of farmers in this country were forced to switch from coffee to tea because of the attack of a mushroom that the plantations resulting from a single stock were unable to cope with. The same happened in 1800 in Ireland, when a pathogen from Mexico attacked the extensive potato crops resulting from a strain with very little genetic variability (and therefore unable to react), causing a severe famine in which nearly 2 million people died.
In Italy at this time about 500 species are at risk, further subdivided into varieties. In agriculture the main cause of genetic erosion is the genetic improvement of some more productive cultivars, which become more sought after by producers, to the detriment of the others.
For this reason, the Institutes located in various parts of the Planet are not enough, where they try to conserve biodiversity. The collection in refrigerators has not given the desired result: the simple preservation of the seeds also leads to the loss of variety because it is not said that the seed can be germinated at the right time.
It becomes necessary to exchange and continuously circulate the seeds. This is why the associations of “free exchange of seeds” were born and are born in the world. These associations actually attempt to reintroduce the ancient peasant practice that was, until a few decades ago, the true and only guarantor of genetic variability.
We remind here, for those who were not involved in questions of ecology and energy systems of Nature that, under conditions of greater biodiversity, this ensures the best use of resources (sun, soil, water, etc.), allowing the best performance for all living beings (Including man) that compose it.
The statement therefore that genetic selection, in favor of cultivations in purity, will feed the world is based on a scientifically incorrect axiom.
So why did it get so much? There are two fundamental factors:
The erroneous belief that agriculture was similar to industrial processes and methodologies;
The idea that purity was the solution to the poverty of the world (remember that the past century saw in some advocates of genocidal purity, wars and destruction).
The story does not stop and we can not cry on us but we need to make everyone understand, from scientists to politics, that the time available is not much: for every lost gene we conceive an increasingly poor humanity.
Guido Bissanti