Turning on the power: New maize protein quality
test for developing country labs

CIMMYT chemistry consultant Eric Nurit, third from left, with staff from the International Institute of Tropical Agriculture (IITA) in Ibadan, Nigeria.

Chemist Eric Nurit recently visited six African countries to teach scientists and lab technicians a new, cheap, fast and reliable lab procedure for measuring protein quality in maize grain. CIMMYT and partners have been developing and disseminating quality protein maize (QPM) since the 1970s. The new method will speed QPM breeding and help ensure quality in seed for farmers.

“I was in Ethiopia and couldn’t understand why the new lab procedure wasn’t working after two days,” says Eric Nurit, chemistry consultant in CIMMYT’s maize grain quality lab. “Finally, I tested the pH of the lab’s water, and realized it was skewing the results. Once we adjusted this, the procedure came off without a hitch.”

Nurit recently worked with lab scientists in Ethiopia, Ghana, Mozambique, Uganda, and Zimbabwe, helping them to implement a new method to assess protein quality in maize kernels. He deems his six weeks of work successful, but also found the trip—his first in the region—an eye-opener, with regards to the difficulties under which his African colleagues must operate, including old equipment, high turnover of staff, and frequent power cuts.

“Overall the scientists were very enthusiastic, well-trained, and eager to learn the new procedure,” says Nurit. He was impressed by staff dedication at many labs. For example, one technician at the Crop Research Institute in Ghana stayed overnight in the lab, turning on the refrigerator’s generator each time there was a power cut, to ensure that the maize samples remained for 16 hours at 18.3º C so they could be analyzed.

A better way to measure protein quality

Lab technician Ilo Emeka applies the new lab method for measuring protein quality in maize grain at the International Institute of Tropical Agriculture in Ibadan, Nigeria.

Quality protein maize (QPM) has about twice the lysine and tryptophan, essential amino acids for protein for humans and monogastric animals. QPM can benefit the poor—particularly children—in developing country areas whose inhabitants have maize-heavy, protein-poor diets. It can also serve as an inexpensive protein-enhancer for pig and poultry feeds; a leg up for small-scale farmers who cannot afford or obtain costly feed supplements to raise farm animals.

Because QPM looks like normal maize, breeders need lab analyses of grain protein quality to select the right plants in their programs. Companies or community groups who produce QPM seed for farmers must also regularly monitor its protein quality through lab tests. Cereal chemistry labs have typically used an acetic acid mixture to measure tryptophan in maize kernels. “The acid was hard to get in many countries, inconsistent in its purity, and required in large quantities for the tests,” says CIMMYT maize nutritional quality specialist, Natalia Palacios.

QPM testing closer to home
Through painstaking trials, Nurit and Palacios developed a cheaper, faster, and much more reliable method. The new approach lends itself to automation, frees up time for lab technicians, and can be adopted more readily by labs in developing countries. It is now routine at CIMMYT and the International Institute of Tropical Agriculture (IITA), and several laboratories in Africa and other developing country regions where QPM is of interest.

“In the past, breeders or seed producers needed to send their samples to CIMMYT or other advanced laboratories—a slow and costly procedure,” says Palacios. “Now, with the help of people like Eric, we’re empowering labs and researchers in developing countries to do reliable testing for protein quality in maize kernels.” According to Palacios, this should promote the spread of QPM, which is currently sown on more than 0.65 million hectares in 25 developing countries.

The experience of Nurit meanwhile provides a better idea of teething problems a new procedure might face in the labs of CIMMYT’s partners—valuable information, given the center is spreading the new procedure to labs in Colombia, Honduras, Venezuela, and elsewhere. “Bringing the new method to people in developing countries made me feel very positive about my work, and made the months of honing the technique worthwhile,” says Nurit.

For more information: Natalia Palacios, maize nutritional quality specialist (n.palacios@cgiar.org)