As people in four countries - Yemen, South Sudan, Somalia and Nigeria - teeter on the brink of famine, it seems our progress towards ending hunger is sadly inadequate. We are once again confronted with the question: how can we do more for vulnerable communities?

We have, in fact, made major strides: global hunger is at its lowest level despite population growth. But some regions lag behind, with catastrophic consequences. This is because a host of new challenges, such as unprecedented temperatures and rainfall extremes, are coming together with timeless challenges, such as conflict and natural disasters, to block our quest for zero hunger.

We need to use all the tools at our disposal to make a world free from hunger a reality, but one major ally isn't getting the global attention it deserves: crop plant biodiversity.

Crop plant biodiversity is the term used to describe all the genetic resources for any crop plant - either growing today or previously collected. This biodiversity has hardy traits such as disease resistances and heat tolerance built in. Over thousands of years, farmers worldwide have evolved a diverse array of food crops based on these traits. Plant breeders have used these genetic resources for decades to breed food crops more resilient to shocks and stresses, ensuring food and nutritional security for ever-growing numbers of people.

But our biodiversity habitats, where these genetic resources are naturally found, are shrinking. Global plant and animal biodiversity declined 30 percent between 1990 and 2007, twice as much in tropical regions. We cannot afford to let this continue.

Biodiversity helps us protect food supplies and our environment

We know sustainable agricultural practices are crucial to ensuring food and nutritional security for future generations, but they are also crucial for ensuring the health of our environment, which preserves biodiversity habitats.

This biodiversity can then be used to breed food crops that are resistant to pests, diseases and drought, enabling farmers to use less fungicide, insecticide or water on their farms, thus reducing their impact on the environment.

Recent work at the International Maize and Wheat Improvement Center (CIMMYT), for example, has identified maize varieties resistant to the Tar Spot Complex Disease. They are now being used by smallholder farmers in southern Mexico, whose crops have been severely affected by the disease, while plant breeders also use them to develop new disease-resistant varieties.

READ MORE: Who is affected by climate change, and how?

New crop varieties also often improve yield, making existing farmland more productive and reducing the need to clear more land for agriculture. This conserves more area for biodiversity habitats and reduces the greenhouse gas emissions associated with deforestation. This has been a major priority of initiatives such as the Global Environment Facility's new programme on fostering sustainability and resilience for food security in 12 countries across sub-Saharan Africa, which we believe could mitigate 20 million tonnes of carbon.

Seeds save lives and restore livelihoods after conflict and natural disasters

Seeds are nature's way of conserving and passing plant biodiversity from one generation to the next. For the same reason, collecting and conserving seeds in library-like seed or germplasm banks is critical for food and nutritional security. When natural disasters strike – like Typhoon Haiyan in the Philippines, or Hurricane Mitch in Honduras – the seeds that farmers rely on for food and income can be wiped out. Farmers in the Philippines and Honduras recovered the seeds of lost varieties thanks to the germplasm bank that CIMMYT maintains. This germplasm bank contains 170,000 maize and wheat varieties from across the globe.

READ MORE: First seed library sprouts in Palestine

Conflict also threatens seed supplies. Maize seed from CIMMYT, adapted to Rwandan conditions, assisted farmers to return to their lands following the horrors of the Rwandan genocide.

Just like a sound investment portfolio balances short-term opportunities with long-term security, ramping up investment in enhanced conservation and understanding of crop plant biodiversity now, could secure a future without hunger.

These examples show that we never know where, when or who the need to rely on biodiversity will hit. It is our greatest insurance policy against the unforeseen challenges to food security that you, or your children, may need.

So what must be done to bring crop plant biodiversity to its rightful role in eliminating hunger?

Time to ditch short-term solutions

As we react to a persistent series of acute crises, such as localised famines and natural disasters, we are tempted to delay investing in the long-term solutions like those associated with genetic resources, as they take years, sometimes decades to reach farmers.

However, just like a sound investment portfolio balances short-term opportunities with long-term security, ramping up investment in enhanced conservation and understanding of crop plant biodiversity now could secure a future without hunger.

Identifying the genetic resources useful for a specific and often unanticipated need, such as a newly emerging crop disease, can be like searching for a needle in a haystack. But investing today in characterising the collections stored in germplasm banks can greatly accelerate the speed of this search. Think of it like cataloguing books in a library – by genre, subject, language, author, page count, etc. – to help you find the right book quickly. The difference is, this book could stop a famine before it begins.

The more we know about our genetic resources, the more quickly and effectively we will be able to use them when responding to future needs. And the more practice runs we perform, working with plant breeders or farmers to enrich their crop varieties for needed or desired traits using genetic resources, the better prepared we will be.

Ensuring that crop plant biodiversity is protected, conserved, categorised, made available and used may be our best strategy to end hunger.

Today, on the UN International Day for Biological Diversity, let's push forward on making sure that biodiversity is recognised as one of our most important allies in ending hunger and securing food for this and future generations.

Mohamed Bakarr is Lead Environmental Specialist at the Global Environment Facility (GEF).

Kevin Pixley is the Director of the Genetic Resources program at the International Maize and Wheat Improvement Center.