Escaping Striga's stranglehold

It looks almost idyllic, a meadow full of Striga in bloom. But Striga's impact on Africa's small farmers is disastrous: up to 90% of harvests are lost. Is this the super weed that no crop can stand up to? Harro Bouwmeester thinks otherwise.

Striga parasitizes cereal crops such as maize, millet, barley, and sorghum, which are cultivated all over the African continent. Striga attaches to the roots of a host plant and withdraws the nutrients it needs from the host. The parasite finds its host by tracing signal compounds from the host's roots. The cause: phosphate deficiency. ‘The grain crops use these signal compounds to attract symbiotic fungi,' Bouwmeester explains, 'which take up nutrients from the soil and supply them to the plant in exchange for sugars. But the Striga plant also responds to these signal compounds. Now, because fields in Africa are increasingly phosphate-poor, the crops produce more and more of these signal compounds. This is how millions of hectares in Africa have become infected.'

Supplying more phosphate is not an economically viable option. ‘We want to create crops that are resistant to Striga, and do that by investigating the signal compounds,' says Bouwmeester. 'We need plants that do make the signal compounds for the fungi that the grain crops need, but not the ones that the Striga recognises.'

In addition, Bouwmeester wants to study how to achieve the maximum result with the minimum amount of phosphate. 'I want to find solutions that cost next to nothing. I want to understand how these signal compounds work, and then apply that knowledge in the field to solve the problem. Striga is one of the major reasons why Africans do not have enough to eat. That in itself shows how incredibly important it is to move forward with this. And that is something we can do in Wageningen; our strength is connecting fundamental research with application.'

Prof. Harro Bouwmeester, professor of Plant Physiology

Back to all projects about global food challenges