As climate change spreads its tentacles across the world, it is the food supply that will be directly hit by rising temperature, erratic rainfall and abnormal spread of pests and diseases. A recent meeting organized by the UN stressed on the need to conserve agricultural biodiversity which could provide climate-resilient DNA for raising hardy crops to feed the planet in future

Genetic resources stored in gene banks will provide the plants the capacity to cope with a variety of environmental conditions in a warming world. (Image by CIAT)

Some international environmental meetings get more coverage and attention than others. Every time there is a meeting related to the UN Framework Convention on Climate Change, it gets the attention of the world. Meetings of the UN Convention on Biological Diversity get less attention. And when a meeting that links agricultural biodiversity to climate change is held, it goes almost unnoticed.

In January, the Food and Agricultural Organisation (FAO) of the United Nations organised a meeting of the Commission on Genetic Resources for Food and Agriculture (CGRFA) in Rome. This meeting had an important objective to review and strengthen the mechanism to preserve agricultural diversity to deal with climate change.

Most of us are fussy about what variety of rice we cook for our lunch or the wheat we use for our roti. We like aubergines of a particular colour and size and a particular kind of mangoes in summer. As effects of climate change come into play, perhaps some of these varieties may not be available. The production of cereals, vegetables and fruits may be affected in India.

According to a report called Coping with climate change: The roles of genetic resources for food and agriculture, released at the meeting, India is one of the countries where climate change could adversely affect food production. The report states: “Studies indicate a general trend towards the loss of cropping areas in sub-Saharan Africa, the Caribbean, India and northern Australia, and gain in the northern United States of America, Canada and most of Europe.”

Although farmers have always adapted their cropping systems to adverse environmental conditions, the speed and complexity of climate change pose problems on an unprecedented scale, the report adds. “There is evidence that climate change has already negatively affected wheat and maize yields in many regions.”

The changing climate can affect the very ecosystem in which farming is done. The change in temperature could affect the population dynamics of insect pollinators and flowering time for the crops. Thus, when the crops are ready with their flowers, there may not be pollinators to help them mate and reproduce. If pollinator population could change with temperature so could the number of disease vectors, thereby increasing the propensity for crop diseases and pest attacks.

The importance of genetic diversity

This is where the importance of the diversity in genetic resources comes into play. Genetic diversity gives plants the ability to deal with a different and changing climate. Plant varieties that can withstand the climate pressures of the future will evolve as a result of this diversity.

Crop breeding aims to develop varieties and hybrids that are able to withstand pressures from present-day pests, diseases, droughts, floods and storms and still produce substantial yields. But, when the temperature, frequency of extreme weather events, spread of pests or the onset of diseases change, then new varieties have to be developed. To develop these, the genetic resource will come from those stored in farms or in institutional gene banks.

There is a caveat though. Crop breeding takes time, and it can take years before a new variety or hybrid is developed. Therefore, to be climate resilient in future, the breeding has to start now. Genetic resources with traits that will provide the plant the capacity to cope with a variety of environmental conditions will become even more important.

The meeting held at Rome was important for agricultural genetic resources since the CGRFA implements the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA).  This is a legally binding instrument that covers conservation and sustainable use of plant genetic resources for agriculture and ensures equitable benefit sharing. It has developed a multilateral system for access and benefit sharing for 35 crops.

The treaty replaced an International Understanding in 2001 (it came into effect in 2004) after the UN Convention on Biological Diversity (CBD) rewrote the rules on ownership of genetic resources. Till the CBD was initiated at the Rio Earth Summit of 1992, genetic resources were part of a “common heritage of mankind”. The Convention changed it to “the sovereignty of States over their plant genetic resources”.

Thus, the international treaty has within its ambit the genetic resources stored in gene banks of international and national agricultural research systems. According to the Second Report on the State of the World’s Plant Genetic Resources for Food and Agriculture, the ITPGFRA holds 4.6 million germplasm samples, held in 1,240 genebanks worldwide. The Consortium of International Agricultural Research Centres (CGIAR), a 15-institution partnership, holds more than 740,000 germplasm accessions. The collection of the national agricultural research system in India doubled to 366,000 accessions in 2008 from 154,000 in 1995.

These genebanks are designed to protect genetic resources so that crops can be bred to overcome climate change. However, these genebanks themselves can become casualties during extreme weather events, natural disasters or war and conflicts. Hurricane Mitch of 1998 severely damaged Central American banana germplasm collections, and extreme floods in Ecuador during the El Niño of 1997 destroyed the national cassava collection. Decades of civil war in Afghanistan destroyed the agricultural research infrastructure and so was the case in Timor-Leste.

To partially overcome this danger, in 2008 a global seed vault was created in the Norwegian island of Spitsbergen in the Svalbard archipelago in the Arctic region. Situated in a permanently frozen region, this vault holds backup seeds of 830,000 samples.

While these genetic resources can help scientists breed crops for the future, farmers living in areas where impacts of climate change are already being felt have to adapt in real time. They are conserving, over generations of harvests, the seeds of those varieties that have demonstrated greater resilience to the changes. To deal with climate change, these farmer-conserved varieties will play an increasingly important role.

Whether conserved in gene banks or in farmers’ fields, these seeds carry the genes that can help ensure that we have our food crops when the climate changes. When the temperature in the Gangetic Plains changes, the present basmati varieties that we are used to may or may not be available. But the genetic resources in the gene banks and farms can help ensure that we shall still have rice on our tables.