Across Africa, armies of hungry caterpillars destroy the flowers and pods of cowpeas; casualties can reach 80 percent of this staple food crop if no measures are taken. But the real victims are smallholder African farmers who feed their families on farms smaller than five acres. Next year, they will have the option to grow cowpeas that are resistant to one of these pests.
Scientists report in Plant Cell Tissue and Organ Culture that they have engineered cowpea — one of the most important sources of vegetable protein for rural families in Sub-Saharan Africa — to produce a Bacillus thuringiensis (Bt) protein, which protects against the Maruca pod borer that plagues cowpea. Bt has been used as an organic pesticide for several decades, but it is often unavailable or too expensive for smallholder farmers.
Bt cowpea could yield as much as 25 percent more than other cowpea varieties, said TJ Higgins, a research scientist at the Commonwealth Scientific and Industrial Research Organisation (CSIRO) who led this work.
Bt cowpea could be released next year — at no cost — to farmers in Nigeria, Burkina Faso, and Ghana. In 2009, Higgins began working with colleagues and authorities in West Africa to develop regulatory approval for Bt cowpea.
“Many African farmers do not have to pay for seed, and they will not have to pay anything extra for the Bt cowpea either,” Higgins said. “They will be able to save the seed and re-sow it the following year. There are no additional costs because this work has been publicly funded all the way through.” Read more