Strategies to stop Striga
Strike Two: Resistant varieties

credit: Dr Charlie Riches, NRI

Not all varieties of cereals are affected by Striga. Some have an inherent resistance to the parasite by exhibiting tolerance to the weed - growing well despite its presence - or preventing the growth of the weed at an early stage. In recent years, Striga-resistant varieties of maize have been released in Nigeria by IITA. More recently, varieties of sorghum which have shown some resistance to Striga have been tested in three areas of Tanzania, as another aspect of the collaborative DFID-funded project to find ways of controlling Striga. Farmers in the Lake Zone of Tanzania, near the town of Mwanza and in Central Zone Tanzania near Dodoma, have been actively involved in testing the varieties using their own criteria to make the selections. "They are particularly interested in having varieties that mature early, that produce well on land that is of low soil fertility, and where Striga is a problem," explains Dr Charlie Riches of the Natural Resources Institute working with the project. "They also want sorghum that is palatable."

The varieties eventually chosen by the farmer groups were originally bred at Purdue University in the US. These two varieties, which have since been released by the National Programme, offer some resistance to Striga. The two varieties, now called Hakika (Kiswahili for 'certain' or 'sure' due to its reliability to produce a yield) and Wahi (meaning 'early' as it is an early maturing variety) both produce low levels of the root exudate that stimulates Striga and thus provides some level of resistance.