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Fighting Witchweed in African Sorghum (1/2)

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Farmers in Africa call the striga plant by the name witchweed. It grows a pleasant looking purple flower. But it attacks many crops in the grass family. Witchweed is among the few flowering weeds that act as parasites on other plants.

Every year it causes six to seven billion dollars in damage to African grain sorghum. Sorghum is important to the local food supply. The witchweed steals water and nutrients from the roots and attacks the sorghum with a poisonous substance.

Now, scientists say they have produced seeds that can protect sorghum crops from witchweed.
Kassim Al-Katib is a weed expert at Kansas State University in the United States. Mitch Tuinstra is a genetics and plant-breeding expert formerly at Kansas State but now at Purdue University in Indiana.

To deal with witchweed, they developed special sorghum-seed genes. These genes can accept carefully chosen chemical herbicides without being harmed. The researchers placed the herbicides on the sorghum seeds. Kassim al-Katib said the seeds kill the witchweed as the sorghum grows.

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