The Importance of Diversity
It was with peas - that is to say, the seeds of Pisum sativum - that Gregor Mendel established during the second half of the 19th century a law that would lay the foundation of modern genetic research: the characteristics of individuals can be transmitted from one generation to the next by travelling through the genes.
Genetic composition, within all living things, is often a guarantee of a species’ adaptability to its environment. This is true of plants. What this means is that the more genetic diversity existing within a population, the greater the chance that one (or more) individual within that population possesses a gene that will enable it to withstand environmental disturbance or change. A good example of this can be found in the spruce tree. A few years ago, researchers discovered certain surviving spruce trees within forests almost completely destroyed by one voracious insect, the spruce budworm. This handful of trees had remained intact and alive, completely ignored by the budworm. Scientists then noticed the existence of a gene in these particular spruce trees that was not found within those that had been ravaged. When present inside the tree’s genome, this gene produces a natural repellent that effectively guards against budworm attack. Over the years only individuals with this gene were able to survive the infestation, and they would go on to reproduce and repopulate the forest with trees obtaining, by heredity, the gene for budworm resistance. This phenomenon of species adaptability in the face of unexpected changes forms the basis of the slow but certain evolution of living organisms within an ecosystem. It is a random phenomenon. How is this same process reflected in our gardens and in our fields?
Since the beginning of the “Green Revolution”, many aspects of agriculture have been standardized. Little by little fields have expanded in size and the plants growing within them have been selected for conformity to standards of size, colour, food safety, and harvesting efficiency governed by the pervasive rules of wholesale markets. In parallel to this agricultural standardization and scientific research driven towards the development of so-called perfect and universal seed stock (often selected primarily to yield large harvests rather than strong and healthy plants capable of growing without interventions), we have seen an increase in the use of pesticides, a concomitant rise in pest resistance, and subsequent uncontrollable disturbances that can result in significant damage to fields. In the quest for uniformity, we have moved further away from that which is key: diversity. Diversity is a free and sustainable line of defence against the vagaries of nature, while uniformity often triggers a cascade of problems that lead to costly and polluting measures – the “crutches” needed to prop up a weakened system.
In recent decades, however, we have seen a resurgence of so-called diversified farms. These small-acreage farms, mostly dedicated to supplying local markets, are examples of diversity. On them we find a wide variety of vegetable crops, fruit trees, medicinal plants, forest mushrooms and even animals. Indeed, different pollens naturally attract different types of insects, these insects attract a variety of birds, and in this way diversity continues to increase. This growth of diversity in a multispecies landscape directly contributes to the regulation of individual populations and tends toward overall balance. Again, an agricultural approach modelled on ecosystems could become a force to counter the massive loss of productivity caused by agronomic problems related to large-scale, intensive monoculture. This is the diversity that the agroecology movement is defending. The movement, which is gradually gaining traction, asserts that the observation of and respect for natural processes can form a response to the current agricultural model of intensive replacement inputs. I believe that this approach, with its emphasis on respect for diversity and natural processes, will in time truly define our food security.
By Maxime Boisvert
Maxime lives in La Pocatière, in the Bas-Saint-Laurent region, where he is currently completing his agricultural training. He is particularly interested in traditional and artisanal methods of agriculture and food processing.