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Crop Improvement

Research in crop improvement is providing large returns, but with yields at a plateau, farmers face important challenges. Diseases and pests are constantly evolving, and can sometimes overcome resistance in a plant. ICRISAT plant breeders continuously develop varieties with multiple genetic sources of resistance so they can deploy new cultivars when needed. 

US$ 10 billion - Estimated annual public investment in agricultural research for developing countries

US$ 14 billion - Estimated additional annual investment  needed to cut hunger in half by 2015

50% - Year-on-year net return to investment in developing early maturing pearl millet variety Okashana

As population grows, and as climate change places greater burdens on the semi-arid tropics, consensus is growing that crop improvement research needs investment of more time and money on the crops grown in dryland areas. Assigning a higher priority to these so-called "orphan" crops makes sense from several angles.

First, investments in plant breeding are now nearing record lows, especially in developing countries where they are either stagnant or decreasing. Public investment in agricultural research overall now totals about US $30 billion per year, but only about a third goes to developing countries. Of that amount, the lion's share is invested in the big three cereal crops - rice, wheat and maize - and only a small fraction is directed to the dryland crops grown by the poor. 

Despite this historical disparity, or perhaps because of it, growing numbers of scientists are optimistic that big gains can be made to increase the yields of the dryland cereals and legumes. They point out that much can be learned from previous investments in the big three cereal crops that can now be applied to dryland cereals and grain legumes. In addition, if more funding is made available – as is now happening under a re-organized CGIAR – large yield increases could be achieved in a comparatively short period of time.

But can plant breeding really achieve that much in the harsh conditions found in drylands regions? Apparently, yes, if better varieties are combined with better crop management. Economic analyses indicate that in Africa alone, farmers now grow improved varieties on more than one million hectares. Adoption rates for improved pearl millet (34%) and sorghum (23%) across southern Africa are particularly remarkable.  

Throughout Asia, a large portion of the dryland cereals and grain legumes grown by farmers these days have benefitted to varying degrees from investments in crop improvement. Parental material and advanced lines from ICRISAT are being widely used to produce higher yielding and earlier maturing cultivars that are tolerant of various abiotic stresses – especially drought – and that carry built-in resistance to the major pests and diseases that can severely limit production.

What traits do farmers and consumers want?

The process of breeding new crop varieties almost always starts with a question: what do farmers and consumers want? In dryland areas four characteristics stand out: early maturity, higher yield, resistance to diseases and insects, and better grain quality, a prerequisite for commercialization.

Farmer participatory selection in Samanko, Mali.
Over the past 40 years, plant breeding programs have helped ease seasonal hunger in Asia and sub-Saharan Africa by developing varieties that are not only higher yielding, but mature weeks or even months earlier than traditional varieties. Improved, early maturing varieties also help to reduce risk when the rains end earlier than expected and provide crop varieties that smallholder farmers can harvest when prices peak.​​

Large gains have also been achieved by developing resistance to such diseases as downy mildewin pearl millet, fusarium wilt in chickpea and pigeonpea, and rosette virus in groundnut. Insect resistance will likely be harder to achieve, but large gains are more than possible for such insect pests as legume pod borers and sorghum midge.

As plant breeder well know, the ultimate success of new breeding lines depends on consumer preferences and market demand. Consumers and processors place a high value on taste, texture, appearance, ease of preparation, and storage. In addition, urban and export markets demand specific, uniform quality characteristics. Indeed, improved grain quality can substantially raise market value, typically on the order of 20-30%.


Large additional yield gains have been possible with the development of hybrid varieties of pearl millet, sorghum and pigeonpea. For example, improved, fast-growing pigeonpea cultivars capable of withstanding exposure to drought are already helping farmers cope with the early affects of climate change. These new legume hybrids, the first of their kind, routinely out-produce conventional varieties by nearly a third and have gained wide acceptance in India, the world's largest producer and consumer of the crop. Plant breeders believe they could prove equally useful in Sub-Saharan Africa as the continent’s seed industry develops greater capacity.

Economic impact

Are development investors getting a good return? In more favorable environments, plant breeding has been shown to deliver value that exceeds its costs many times over. But what about in the dry areas, where gains are harder to come by?

Return-on-investment studies cannot be conducted for every variety released, but several examples suggest that these efforts provide extremely high rates of return. For example, a three million dollar effort to create and disseminate the early-maturing pearl millet variety Okashana 1, released in 1989 in Namibia, was estimated to return net benefits worth 50% of the investment, year after year - a rate of return that far outstrips most financial instruments.

Similar returns were recorded for sorghum. Improved varieties released in 1995 for the Nigerian food industry were evaluated in 2002 and estimated to be earning a 62% annual return on investment. A sorghum variety released in Chad (called S 35) generated even more spectacular results: a 95% return on investment per annum, generating about US$ 4 million per year in net benefits to the poor.

Cash value is of course not the only measure of success; the alleviation of human suffering is a priceless good in its own right. Nor do such studies assess all of the indirect benefits of economic growth and employment stimulated by the success of a new crop variety. These would include, for example, the training of national scientists, and increases in incomes and jobs associated with small-scale agricultural input supply, crop processing, and marketing. 

Pearl millet variety ‘Okashana 1' in Namibia, selected largely by farmers, matures 4 to 6 weeks earlier than previous varieties greatly reducing the risk of crop failures and helping farmer sell their crops when prices peak. It proved so popular that within just a few years it covered half the country's millet-growing area. 
New chickpea varieties are spreading rapidly in Ethiopia because consumers value their large-seeded ‘kabuli' (garbanzo) type grain. Similarly, large, creamy-white seeded improved pigeonpea varieties are gaining market share in Mozambique and Tanzania for export to India. 
Farmers compare the grain attributes of pigeonpea varieties at the Chitedze Research Station, Malawi.