Ibadan, Nigeria
June 9, 2010

Scientists working at the International Institute of Tropical Agriculture (IITA), African Agricultural Technology Foundation (AATF), and the Agriculture Research Service of the United States Department of Agriculture have identified strains of fungi native to Kenya that could solve large-scale grain contamination from aflatoxins and save millions of people.
When applied in the fields, these non-toxic-producing strains, also known as atoxigenic strains ‘competitively exclude’ and displace the aflatoxin producers and, as a result, dramatically reduce the levels of contamination in the field before the crop is harvested, says Dr. Ranajit Bandyopadhyay, IITA Plant Pathologist, who developed aflasafe™ – a product provisionally registered for the control of aflatoxins in Nigeria.

“During harvest, the atoxigenic strains are also carried from the field to the stores. So, even if the grains are not stored properly or get wet during or after harvest, as it is happening in Kenya this year, the atoxigenic strains will increase instead of the toxigenic strains, resulting in reduced aflatoxin contamination during the post-harvest period,” he added.

Although the relative severity of maize contamination in Nigeria is less, Kenya has been hit by high levels of lethal aflatoxins caused by inappropriate storage of maize by farmers in the drought- and famine-prone Eastern Province with a child reportedly killed after consuming contaminated maize.

The contamination has also rendered at least 2.3 million bags of maize unfit for human and livestock consumption and trade, to the dismay of the millions of small-scale farmers that depend on the crop for food and income.

According to Dr. Peter Cotty of the USDA, the high rate of aflatoxin contamination in Kenya is a result of the dominance of the S strain of the fungus (Aspergillus flavus), which is known to be among the most potent producers of aflatoxins ever found.

“The S strain produces very high levels of aflatoxins. In the United States, biocontrol with atoxigenics has successfully reduced contamination by the S strain,” said Cotty, who partnered with IITA on the work.

Produced by A. flavus, aflatoxins hurt not only human health but are also non-tariff barriers to both domestic and international trade since agricultural products that have more than the permissible levels of contamination are rejected.

Besides, the toxins are also potent causes of cancer and they suppress the immune system causing humans and animals to be more susceptible to diseases.

Between 2004 and 2006, nearly 200 unsuspecting people died after eating highly contaminated maize.

However, in Nigeria, maize farmers that participated in aflasafe™ trials were able to reduce aflatoxin contamination by 80% by broadcasting 10 kg/ha aflasafe™ 2-3 weeks before maize flowering.

Consequently IITA, in partnership with the Nigerian government and the United Nations Industrial Development Organization (UNIDO), is working on obtaining full registration and identifying an entity that would mass manufacture, market, and distribute aflasafe™ in Nigeria to save the health and income of millions of families.

The biocontrol approach, if replicated with the identified Kenyan non-toxic strains, stands to offer the same benefits in Kenya, according to Bandyopadhyay.
 

Website: http://www.iita.org

Published: June 9, 2010