Source: The Global Crop Diversity Trust

THE GENETICS OF WATER

Supply, Demand, Conflict

A recent cover article by Fred Pearce in the New Scientist illustrates agriculture's profligate use of water in a manner we can all visualize: "Every teaspoonful of sugar in your coffee requires 50 cups of water to grow it, according to Pearce. “Growing the coffee itself requires 140 litres of water, or 1120 cups.” A kilo of rice, moreover, requires an astonishing 3-5,000 litres to grow. That’s 2-3 Olympic-size swimming pools per ton. According to the New Scientist, “our demand for water has turned us into vampires, draining the world of its lifeblood.” Strong language.

The global signs of an impending water crisis, however, could not be much clearer. Consider the following:

• Freshwater consumption rose twice as fast as population growth in the 20th century. Today, we grow twice as much food as a generation ago, but we use three times more water to do so.
• Approximately 70% of all water used by humans is for irrigating crops. Groundwater supplies in major agricultural regions are being overdrawn, depleted at a much faster rate than their replenishment by rains. As the New Scientist puts it, “Each aquifer has its own countdown to destruction. As each bubble bursts, it will undermine the world’s ability to feed itself.”
• Drought, such as that being experienced today in East Africa, and recently experienced in Australia and the USA, prompts even greater tapping of stored supplies while dramatically reducing the rate of replacement. The incidence of drought may be increasing. Furthermore, the rise in surface temperatures, and the prospect of further warming, will put additional stress on crops and further increase demands for water.

By 2025, 1.8 billion people will live in a situation of absolute water shortage. Fully two-thirds of the world’s population will live in what FAO describes as a situation of water stress.

Hottest Dozen Years on Record
(since 1880)*

*Source: Union of Concerned Scientists 

Population growth, urban expansion and increasing industrialization will intensify competition for water supplies and increase the likelihood of violent conflict. Already, major powers are warning that climate change will fuel future conflict, pointing to lack of water as a contributing factor in tragedies such as that unfolding in Darfur. More than 200 major river basins in the world - major sources of water for agriculture - are shared by two or more countries. Think of the Nile that flows through some of the poorest and driest countries in the world: Ethiopia, Eritrea, Burundi, Rwanda, Zaire, Kenya, Tanzania, Uganda, Sudan and Egypt.

Exacerbating this tension is the need to increase food production to satisfy growing populations, which in turn will require yet more water. Or, alternatively, much better use of available supplies.

Responses and Resources

Two options are immediately evident: agronomic and genetic. Changing common farming practices on a meaningful scale is neither easy nor quick. Producing “more crop per drop” appears more immediately promising. “The greatest gains in water productivity can be attributed to crop breeding efforts,” according to a publication from the Comprehensive Assessment of Water Management in Agriculture, co-sponsored by Ramsar, FAO, the CGIAR and the CBD. “Crop varieties that yield more with the same amount of water, or shorter duration varieties that consume less water, increase productivity of water. Drought-resistant varieties help to stabilize yields, and reduce risks in drought-prone rainfed areas.”

Plants employ a wide range of tactics in response to water and heat stress. Some have extensive root systems, while others develop dense leaf canopies to shade the surrounding soil. Some employ physiological mechanisms to store moisture, while others mature early to reduce risk of water shortage. Plant breeders are searching genebank collections today for traits such as these.

At least two major global efforts are now underway to find solutions to agriculture's water crisis:

• The "Generation Challenge Programme" brings together national agricultural research systems, university institutes and CGIAR Centers to generate a set of genetic resources, scientific tools and technologies with a focus on those addressing the problem of drought. The Trust and the Generation Challenge Programme have agreed to collaborate to identify and promote the identification of promising traits in genebank collections.

• The "Challenge Programme on Water and Food" likewise mobilizes multiple partners in a global effort to identify and develop genetic resources with water-efficient, high-yield potential.

There is cause for optimism. In southern Africa, farmers have planted CIMMYT’s new drought-resistant maize on 250,000 hectares. The African Rice Center’s “NERICA” rice, with improved ability to thrive in harsh environments, is currently planted on 100,000 hectares. Working with ICARDA-supplied germplasm, national research programmes have developed and released dozens of drought-resistant varieties since 2000. Research institutes across Australia are releasing drought tolerant wheat, sorghum, lupins and other crops in response to the worst droughts in the country’s history and what scientists at Melbourne’s Monash University contend is the possibility of “permanent drought” due to changing wind and rainfall patterns.

Today, scientists and farmers contend with a triple threat – the depletion of accumulated water resources, drought, and rising temperatures. Around the world, in country after country, researchers are screening genebank collections for natural traits to help crops and societies respond. The Global Crop Diversity Trust is working to ensure that those genebank collections are well conserved, healthy and complete, because what we save, or don’t, will shape agriculture’s future and our own.

Our greatest water resource may turn out to be the genepool.

TO LEARN MORE ABOUT THE TOPIC

• UN-Water (the United Nations inter-agency mechanism for agencies, departments and programmes involved with water-related issues)
• The UN Environment Programme freshwater portal
• The World Water Council
• Global Water Partnership
• The Generation Challenge Programme
• The Challenge Programme on Water and Food
• International Water Management Institute

HAPPENING AT THE GLOBAL CROP DIVERSITY TRUST

“The Genetics of Water” is the first installment in what will become a regular series of brief “thought pieces” produced by the Trust. Some pieces will be historical in nature; others scientific; others more eclectic and harder to pigeon-hole. All will explore one or more of the countless ways in which crop diversity relates to or touches upon the life and future of this planet and its people. We hope you will come to enjoy them. Let us know if you do; or even if you don’t.

On February 15, Kenya became the 22nd country to accede to the agreement to establish the Global Crop Diversity Trust when its Minister of Agriculture, Hon. Kipruto Arap Kirwa, signed the document at a formal ceremony at FAO. For a list of other countries that have signed the agreement, and for photos of the signing ceremonies, visit our website at www.croptrust.org. And that reminds me: in the coming weeks, our website will get an overhaul, courtesy of the Syngenta Foundation. Several design studios will submit proposals to the Trust with the winner getting the Foundation-funded job of implementing their design. Stay tuned!

The Trust is providing financial support to the Vavilov Institute in Russia to secure their valuable collections of forage and legume seeds. The Institute, in cooperation with countries in Central Asia, will plant, harvest and then return new seeds to the genebank of more than 12,000 different samples. Without such “renewing,” seeds eventually lose the ability to germinate and die. Left unchecked, the sample and its diversity will eventually be lost, permanently. Sergey Alexanian of the Vavilov Institute, and Ken Street of the International Center for Agricultural Research in the Dry Areas (ICARDA) visited Rome to review progress and plan the next three years of this project.

Fernando Gerbasi, chair of the Interim Panel of Eminent Experts (the Trust’s interim board) and I are writing a series of short monthly letters about the Trust – its governance, mission, vision and funding – in the run-up to the first meeting of the Governing Body of the International Treaty on Plant Genetic Resources for Food and Agriculture. The Governing Body will meet in Madrid in June, and will consider matters of direct concern to the Trust, including a Relationship Agreement and the process for appointing four members to the Trust’s future Executive Board.