Blog - Field notes on diversifying the agricultural impacts of our research
PhD student Tara Wight reflects on the balance that should exist between new innovative and native heritage crop varieties after her placement with Nourish Scotland and Scotland The Bread.
(Author: Tara Wight, Editor: Aranza Díaz)
Over the past century, advances in molecular biology have greatly expanded our understanding of the remarkable world of plants. We can photograph what is happening within a single plant cell, trace the history of a species through the intricacies of its DNA, and accurately measure how plants turn gene expression on and off in response to changes in their environment.
I have always been fascinated by the ways in which these advances can touch our everyday lives. In particular, I am interested in how our food and agricultural system has changed, and will continue to change, as we learn more about the workings of plants and develop new technologies to alter them.
In the summer of 2020, I had the opportunity to carry out an internship placement with Nourish Scotland, a charity campaigning for a more sustainable food system in Scotland, and Scotland The Bread, a mutual benefits society who grow and mill local heritage varieties of bread wheat in Fife. I was really excited to do this, because as a crop researcher, it gave me the opportunity to see the sustainable agricultural sector from a completely different perspective.
As part of this placement, I worked with farmers, millers, bakers and campaigners to carry out a piece of research about the potential for local grain systems in Scotland. The report I put together about this research can be found here.
I also learnt all about heritage grains. At Scotland The Bread, they grow a genetically diverse range of old grains, including three varieties of wheat originally bred in East Lothian more than 100 years ago. These older varieties of cereal look completely different in the field to the crops we are used to seeing. The plants are tall and heterogenous, each with its own character, waving elegantly in the wind. Below the soil, the farmer tells me they have a much more extensive root system than modern cereal varieties, which makes them better to cope with variable weather. Many of these heritage wheat varieties have awns, long delicate bristles growing from the ear, which photosynthesise in a more water efficient manner than leaves and can help the plants tolerate drought. Molecular analysis performed in collaboration with the James Hutton Institute has also shown that these grains are significantly higher in nutrients than modern varieties, which contributes to their distinctive flavour.
Of course, there are also down sides to growing these heritage cereals. Yields tend to be lower than for modern crops, the flour produced requires a little more skill to bake with, and it’s harder to process such tall plants with a combine harvester. Nevertheless, this placement made me see some of the advances in agriculture, due to innovation in molecular biology, in a different light.
I have found that the scientific community tends to focus a lot on the impact of our research on the development of new crop varieties. This is not without reason: the use of modern selective and molecular breeding techniques as part of the ‘Green Revolution’ in the 20th century led to the development of high yielding crops which have been invaluable in the fight against food insecurity. However, the widespread use of modern crop varieties has been accompanied by a dramatic decrease in the diversity of the crops we grow. For example, while there used to be many thousands of locally adapted and genetically diverse ‘landraces’ of wheat grown across the world, today these are grown on only 3% of the land used for wheat. Many of these traditional cultivars have been lost, and almost all the wheat we consume comes from just a small number of high-yielding modern varieties.
Additionally, crop improvements are inclined to focus exclusively on major world crops, at the expense of local, traditional species. Most of the world now lives of just 12 species of plants. The decline in the range of types of crops grown leads not only to a loss of genetic diversity, but also to a loss of culture and tradition surrounding cultivation. Scientists tend to have a very good understanding of the importance of maintaining genetic diversity, however, the market will always favour the higher returns promised by a new variety, leading to a steep decline in the number of other varieties grown.
My work during this placement made me consider that perhaps in our quest for the new and improved cultivars, we may overlook the value of some of the crops we already have. The Scottish varieties of wheat grown by Scotland the Bread were lost for almost a century, and their notable nutritional benefits were only very recently discovered. In focusing our agricultural advancement extensively on the development of new varieties, we risk losing forever a wealth of genetic diversity which could be essential in the future for helping our food system adapt to environmental challenges.
I am increasingly interested in the potential of molecular biology to be used to improve our food system beyond the paradigm of crop genetic improvement. For example, “how can we use scientific advancements to learn more about rare crop plants, and how can this knowledge help us to improve our cultivation of genetically diverse varieties?” “What can we learn from traditional knowledge of plants, and how can our understanding of their molecular biology explain observed phenomena?” Would learning more about a plant’s innate responses to environmental stress allow us to harness these responses in agricultural practise?
While recognising the important contributions of improved crop varieties, I think there is scope to broaden our thinking on how we can use molecular biology to improve sustainable agriculture and support the resilience of our food system in the face of climate change.