He says that the technology's ability to continue working even when the grain is in storage ensures the safety of maize from aflatoxin contamination. "These atoxigenic strains are also carried in the grains from the field to the stores. So, even if the grains are not stored properly or get wet during or after harvest, as is happening this year, they continue to prevent aflatoxin contamination during the postharvest period," said Dr Bandyopadhyay.
Aflatoxin is a silent killer that causes liver cancer and suppresses the immune system. It also retards growth and development of children. People exposed to very high aflatoxin concentrations experience liver failure and rapid death. From 2004 to 2006, nearly 200 unsuspecting people in Kenya died in this manner after eating highly contaminated maize. Aflatoxin is a colorless chemical that is invisible and only laboratory tests can confirm its presence and contamination levels.
Kenya is one of the world's hotspots for aflatoxin. Research performed by one of Dr Cotty's graduate students, Claudia Probst, has shown that in areas where aflatoxin is a persistent and serious problem, there is a very high occurrence of one of the most toxic strains of A. flavus in the world, the S strain.
According to Dr Cotty, the S strain produces very high levels of aflatoxins and dominates in regions where contamination is very high, including some areas of the US. In Africa, this S strain has been only found to be dominant in the severely affected regions of Kenya. In the US, biocontrol with atoxigenics has successfully reduced its contamination.
In Nigeria, IITA has obtained provisional registration of the technology under the name Alfasafe, a mixture of four atoxigenic strains of Nigerian origin. In 2009, maize farmers in Nigeria were able to reduce aflatoxin contamination by 80% by broadcasting 10 kg/ha Aflasafe 2-3 weeks before maize flowering.
|Contact: Kathy Lopez|