One billion people eat too little. One billion others eat too much. One-third of all food harvested around the world is lost or wasted. Our global food production systems need a drastic overhaul.

Need more evidence? Agriculture today contributes one-third of global greenhouse gases emitted. Farming today is depleting soil and water, destroying forests, and hurting the planet's biodiversity. The more food we grow, the more we destabilize the climate, and the more food we therefore must grow to compensate for crop losses due to droughts, floods, pests and disease.

The world is descending on Rio de Janeiro to map out a vision for a more sustainable and equitable future. The United Nations Conference on Sustainable Development, also known as Rio+20, is the best place to start figuring out how we feed our world as well. What we grow, how we grow it, and who gets to eat it are issues with profound implications, not just for our global food supply, but for our collective quality of life and the sustainability of the earth's system. .

Numerous efforts, from the G8, the Obama administration, and the private sector, have committed tens of billions of dollars to bolstering food security and developing sustainable agriculture. Yet, a disconnect remains between these initiatives and the immediate need to scale up innovations that can produce healthy food, feed hungry people, and still protect the environment.

Rio+20 should ensure support for key approaches and innovations, not just the general principles of sustainable development.

In the span of a generation, Brazil transformed itself from a net importer of food to the world's second-biggest agricultural exporter. Global partnerships and robust government support for agricultural research and development were key. Scientists at Brazil's national agricultural research institute, EMBRAPA, developed soybean varieties and farming practices suited to the dry and acidic plains of Brazil, making the region a breadbasket for the world.

But innovation has not stopped there. State-of-the-art research looks at everything from preventing food waste to developing nutritionally enriched crop varieties. Now Brazil and other rapidly-emerging economies like China are partnering with developing nations in sub-Saharan Africa and elsewhere to extend the benefits of agricultural R&D.

But it's not just about overall investments and approaches. It's also about financing to scale up solutions that work.

In Punjab, India, hundreds of thousands of farmers produce a nearly continuous supply of rice and wheat for up to 500 million people. In a rush to clear the land for wheat planting after the rice is harvested, farmers set their fields of rice stubble ablaze. Climate change is stoking this rush, as rising temperatures are reducing wheat yields by up to 15 percent, increasing the impetus to plant more crops during the winter months. But this burn depletes soil, causes human health problems, and emits about 12 megatons of carbon dioxide.

Two badly needed alternatives to burning are in early stages of use. The locally manufactured tractor-drawn "Happy Seeder" machine cuts and lifts the rice straw, sows wheat seeds, and deposits the straw as mulch. Also in the Punjab, a new biomass-based power plant will use paddy stubble as fuel. It will collect farm residue and sell power to the private sector. Brought to scale, these solutions would improve soil fertility and human health, mitigate climate change, and create local jobs as part of a green economy.

In sub-Saharan Africa about 500 million people eat cassava every day, making it the region's second most important source of carbohydrates. Cassava is also the prime money-making crop for hundreds of thousands of small farmers in Southeast Asia. The hotter the climate, the better it grows, making it a safety net for millions of people as temperatures rise.

But climate change is also bringing increased pest and disease outbreaks that threaten the crop. To fulfill its promise as a failsafe crop in a changing climate, new varieties are needed that further improve drought and cold tolerance, as well as pest and disease resistance. Accelerated improvement of this crop could go a long way to ensuring food security for millions of people in a changing climate.