February 10 marks World Pulses Day. A day dedicated to celebrating beans and lentils doesn’t sound like it’s worth getting excited about, but it should be. Because there are hundreds of forgotten and sidelined bean species that could be game changers when it comes to improving global food security and reducing world hunger.
World Pulses Day was created by the United Nations General Assembly in 2019 to raise awareness of the nutritional importance of legumes: a group of edible grain legumes that are part of the bean family (scientifically known as Legumes Where Fabaceae). Examples include chickpeas, kidney beans, and pigeon peas.
Most legumes, including legumes, have developed the aptitude create their own nitrogen fertilizers from the air through specialized nodules on their roots. This means that these plants can survive in nitrogen-poor soil without the need for external fertilizers, making them very hardy and able to grow from the Arctic Circle to deserts. In addition, this increase in nitrogen gives legumes their high protein content, since nitrogen provides the building blocks for proteins.
The world’s human population gets more than half of its calories from just three harvests: rice, wheat and maize. But these carbohydrate-rich crops require huge amounts of fertilizer and water to grow. The humble bean asks for much less.
There is another problem with relying on a small number of energy-dense crops for food. When not supplemented with more nutrient dense foods, undernutrition and malnutrition can result, which affects children the most.
It is urgent to solve the problem of children malnutrition in parts of Africa such as the Central African Republic and Cameroon, where cassava, another energy-dense crop, is the staple food crop. Cassava contributes to about 40% food consumed in tropical regions of Africa. However, cassava is very limited in nutrients, especially protein, vitamin A, iron and zinc.
The lack of crop diversity also makes us more vulnerable to the worst effects of the climate crisis. In the world first famine caused by climate change has already started in Madagascar, where rice and cassava are the two most important food sources for the population. A UN report calls for major changes in our food system to address poor food security: in particular, increasing crop diversity to guard against the growing dangers of famine, drought and disease.
And as world hunger increases – in part because of the pandemic – we urgently need to help nutritious and resilient food plants grow in the areas they need most.
Which beans are the best?
It is clear that our current food system is unsustainable, especially as global populations are projected to reach nearly 10 billion by 2050. To change that, we need to plant and consume more pulses: starting with rediscovering our common wealth of forgotten pulses.
A kew report has identified at least 7,039 species of edible plants, with the legume family being the most represented: many of which have been overlooked due to our global dependence on the three staple crops.
Not all legumes are created equal. Soybeans, although a legume, are not a sustainable crop due to their high water consumption. He was also a driving force Deforestation, especially in the Amazon. Instead, we can start reintroducing forgotten legumes like lablab and the bambara peanut into our food systems. Many of these beans have links to local traditional knowledge and can help improve regional food security, thereby alleviating world hunger.
For example, cultures like African yam bean growing protein-rich beans and edible tubers (specialized, swollen stems) on a single plant. This bean also replenishes the soil with nutrients and is highly adaptable to different climates.
Due to its tubers – which act as water reservoirs – this crop can withstand drought, so it is used as “safety culturein rural areas of Nigeria to cushion any unexpected loss of other crops. The high protein content of its beans and tubers has also been proven to fight against malnutrition during the Nigerian Civil War in the 1960s. Now categorized as a forgotten crop, this bean has great potential to be reintroduced as an alternative and sustainable source of protein.
And bacteria should not be overlooked: an indispensable tool for reviving the forgotten role of pulses in resilient food systems. nodulation in legumes – allowing them to fix nitrogen and increase their protein content – can only occur in the presence of specific soil bacteria, called rhizobia. As forgotten legume crops are largely understudied, most of the rhizobial partners of these legumes are currently unknown.
Identifying and recording the rhizobia associated with these crops, especially those in their native soils, is important for maximizing nitrogen fixation efficiency and soil health. The field of legume biology must extend its field of research to model leguminous plants (such as Medicago truncatula and lotus japonicus) and commercial legume crops to also include unique forgotten legumes with different physiologies.
In order to take advantage of the superpowers of legumes, we should grow more of them alongside the right kinds of bacteria. This way, we will be in a much better position to deal with any sudden shocks to our food systems.