By Tim Searchinger and Craig Hanson
This post was originally published on the World Resources Institute’s Insights blog.
The world is on a path to need almost 70 percent more crops in 2050 than those it produced in 2006. To close that crop gap without large price increases or clearing more valuable forests and savannas, yields are going to have to grow 33 percent more in the next 44 years than they did in the last 44. This is a tall order—yield growth in past decades was already pretty high, little new water for irrigation is left, and most farmers already use high amounts of fertilizers and other chemical inputs.
So how can the world sustainably secure more food? Use advances in molecular biology to renew the commitment to breeding better crops.
Improving Crop Breeding Through the “Other GM”
Most of the public attention about crop breeding focuses on the pros and cons of genetic modification (GM), which involves taking a select gene from one species and adding it to another. A new WRI publication evaluates the future of crop breeding—including GM as well as conventional crop breeding, which involves sexually combining two whole plants selected for their desirable characteristics. While our findings reveal that GM crops may play a useful role now in helping threatened crops resist disease, most of the gains in crop yields will depend on improving conventional breeding.
Breeding better crops has been a foundation of agriculture for as long as it has existed, yet seeds bred by scientists spread to most of the world only over the past several decades. Improved breeds grow faster, devote more of their energy to the edible parts of crops, and better resist stresses from droughts, poor soils, and pests.
In the past, conventional breeding has occurred in a state of blindness. Scientists could not identify the specific genetic code of genes that drove plants to produce higher yields. Today, due to basic advances in molecular biology, scientists can identify all of a plant’s genes and can cheaply identify how the important genes in one plant differ from another.
Marker-assisted breeding provides one way of using this new knowledge. Researchers screen a large population of new seeds quickly to determine which have the desired gene combinations. They then combine the desirable offspring with each other without having to sow and grow large numbers of seeds and determine which have the desirable traits. Through this technique, breeders produce improved varieties more quickly.
Genomics provides another advance. Through genomics, researchers map and study complete strands of DNA to uncover the complex combinations of genes that confer desirable crop traits. They can then explore combinations likely to produce higher yields.
These improvements in molecular biology build on the pioneering efforts of Gregor Mendel, whose work with peas gave birth to genetics. In that sense, they can be thought of as the “other GM.”
Another opportunity to improve crop yields is to stop leaving important crops behind. No one has precise numbers, but the great bulk of global plant breeding research has gone into the major cereals and oilseeds, such as corn, wheat, rice and soybeans. Yet there are many other crops that are particularly important to small farmers and the food insecure, in part because many of these crops can do relatively well in marginal environments. These crops have become known as “orphan crops,” and include peas and other legumes, beans, cassava, many forms of potatoes, as well as many fruits and nuts.
The limited research efforts undertaken in the past mean these crops have a high potential for yield improvement. Marker-assisted breeding and genomics should also make it easier to achieve quick improvements in orphan crops, in part because they can increase the pace of breeding programs in general. They also make it possible for breeders to understand the gene combinations that have already led to yield gains in more intensely studied crops, such as maize, rice, and wheat. Breeders can then select for these advantageous gene combinations in the orphan crops to achieve yield gains.
Committing to Better Breeding
In Crop Breeding: Renewing the Global Commitment, we make several recommendations for advancing crop breeding. But the cornerstone is more money. The $30 billion in public funding spent on agricultural research and development annually is tiny in light of the human and environmental stakes associated with our food production future. Some countries such as Brazil and China have invested heavily in agricultural research, and they’ve shown remarkable growth in productivity. Private funding has played an important role in the annual improvement of seed lines for major crops, but it cannot support the range of research needed.
The world can no longer boost yields just by dousing them with more water, more fertilizer, more pesticides, and more herbicides. A greater commitment to “the other GM” is a necessary component of a sustainable food future.
Tim Searchinger is a Senior Fellow at the World Resources Institute. Craig Hanson is the Director of WRI’s People & Ecosystems Program.