South Africa is the continent's largest producer of maize.
South African yellow maize futures fell to the lowest level in more than three weeks on forecasts for rain in some of the country's main growing regions.
Yellow maize for delivery in July slumped 3.5% to R2 184 a metric tonne by the close in Johannesburg, the lowest for the contract since January 9. The white variety for March dropped 2.4% to R 216 a tonne.
The town of Welkom in the Free State province, the area that grows about 41% of the nation's maize, has as much as an 80% chance of rain this week, according to the South African Weather Service's website.
Lichtenburg in the North West province, which harvests 14% of the country's grain is also predicted to have rain for the whole week.
"There has been good rain this side," Andrew Fletcher, an independent trader in Kroonstad in the Free State province, said by phone. "The markets had moved up on the basis of no rain and now with rain, we will see the price going down."
South Africa is the continent's largest producer of maize. Meal made from the white variety is used for a staple food known locally as pap, and yellow maize is mostly fed to animals.
Wheat for delivery in March declined 0.7% to R3 805 a tonne. – Bloomberg