Sorghum is more tolerant of drought than other cereal crops like corn, wheat, and barley grown in the US. However, drought still negatively impacts sorghum yields by causing the stomates, or pores that allow the plant to breathe, to close. This stunts photosynthesis and the plant's growth. Pearl millet is even more drought tolerant than sorghum. INTSORMIL scientists are working to develop more drought-resistant sorghum varieties by selecting plants with traits like "Stay Green" that allow the plant to stay alive longer after flowering during drought conditions.

1. Kate Veik
Brief 4 Draft 2 FOR GRADE, REC’D 04/30/10
Sorghum is no Superman.
The crop has proven a better tolerance to prolonged water shortage, or drought,
than cereals common to the United States such as corn, wheat and barley. But, drought
still has an effect on sorghum crops.
All plants have little pores, like the pores on your skin. Those pores are called
stomates. Through the stomates, plants exchange oxygen and carbon dioxide through
photosynthesis and turn the carbon dioxide into sugar. Photosynthesis promotes plant
growth.
Drought essentially plugs the stomates, stunting the growth and yields of the
sorghum, according to Bill Rooney, an INTSORMIL scientist and associate professor of
sorghum breeding and genetics at Texas A&M University.
“It’s like closing your nose or your mouth,” Rooney said. “You can’t breath.”
When the stomates are plugged, sorghum slows down because it has less energy
to burn. Sorghum’s task becomes retaining water to survive rather than to grow so the
sorghum’s growth either slows or the sorghum dies.
Pearl millet is more tolerant of drought than sorghum. Millet’s better tolerance is
illustrated in African farming.
“In areas where they can’t grow corn, they grow sorghum,” Rooney said. “In
areas where they can’t grow sorghum, they grow millet.”
Sub-Saharan Africa experiences the most consistent drought but there is also
inconsistent drought in Southern Africa.
INTSORMIL scientists are working on increasing drought tolerance in sorghum

2. by selecting certain traits scientists know are drought-resistant and bringing those traits
into sorghum.
The Stay Green trait keeps the sorghum plant alive after it has started to produce
grain, or flowered, in a drought.
By infusing the Stay Green trait into the sorghum, INTSORMIL scientists can
help to increase the yield and quality (super power??) of sorghum crops in areas that
experience consistent and crippling drought.