Fighting Witchweed in African Sorghum (2/2)

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Mitch Tuinstra directed greenhouse tests of the seeds in the Netherlands in two thousand five and two thousand six. Similar studies took place in field trials in Mali and Niger. These studies showed the treatment to be highly successful.

Mitch Tuinstra recently returned from Africa, where he met with agriculture experts. They are working to develop local kinds of sorghum that employ the genes. The project is a collective research program under the United States Agency for International Development.

Witchweed has another unusual quality. It requires chemical signals from sorghum seeds to grow. If no sorghum seeds are present, the witchweed seeds can lie under the soil for years. The seeds begin to grow only when they receive the needed chemical signals.

Witchweed seed capsules can hold four hundred to five hundred seeds. Winds and rain spread the parasite. The plant can reduce a farmer's crop. Or it can completely destroy many hectares of grain. Witchweed is very difficult to remove after it invades an area.

Damage from the parasite is worst in dry soil with low fertility. It often strikes farmers who work the poorest land. This can mean disaster for people who already do not have enough to eat.

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