lundi 26 juin 2017

Svalbard et la contrainte génétique !

Ecosystems are the result of both genes and environment influencing each other. The hope of preserving biodiversity by only freezing genes from the past is naive.
....

An insurance policy in the form of a seed vault underestimates the complexity of the interactions between genetics and environment. It also underestimates (or is agnostic about) the impacts of agricultural technology. Agriculture will not be responsible for the apocalypse, but it is so far indispensable for it.
Through agriculture humanity has been narrowing the genetic diversity of our food base, while simultaneously replacing complex ecosystems with pesticide-managed, nitrogen-fueled monocultures. These effects on biodiversity are made possible in part by breeder-driven, chemistry-assisted solutions to farmers’ needs. Those needs are in large part the outcome of ideological and economic forces we have created and which determine how a farm can remain financially viable....
Monoculture agriculture, supported by chemical inputs that benefit from the strongest intellectual property rights instruments ever used, concentrate food supply control into the hands of a small number of companies. Already only three agrochemical companies control over 50 percent of the global proprietary seed market; ten companies control 73 percent. In the United States, three companies hold 85 percent and 70 percent of the patents on corn and other crops, respectively.
Seed banks can certainly play a role in this sea change by contributing to the preservation of genetic diversity. But we cannot rely on genes from the past to breed crops for a future environment lacking soils in which no current plant could ever grow.


Source



---- [je ne traduis pas parce que je suis très fâchée de passer mon temps à faire la police dans des commentaires ineptes !]

Dommage ! car nous sommes au fond du problème ! Enfin !

Il ne s'agit pas de conserver des graines au frais pour protéger la biodiversité car...
La force de la vie est infiniment plus subtile qu'un amoncellement de tiroirs à graines dans une cave gelée.

En clair : les graines si chèrement rangées seront-elles adaptées au nouvel environnement en cas de réintroduction ? 

Certainement pas ! Car un gène évolue avec son environnement autant qu'il le transforme.

Génétiquement, les anciennes graines ne sont plus adaptées au nouveau Monde....

Avant la dépopulation, ils trieront aussi nos gènes. En dessous d'un certain nombre d'humains, le brassage génétique étant impossible, l'espèce disparaîtrait.