It also has the highest production of food energy per unit of human or mechanical energy expended.3

Second, sorghum thrives on many marginal sites. Its remarkable physiology makes it one of the toughest of all cereals. It withstands high rainfall—even some waterlogging.4 Recent research in Israel has shown that it also has some tolerance to salt—an increasingly useful feature for any crop these days.5 But most importantly, it can endure hot and dry conditions. Indeed, it can produce on sites so burning and arid that no other major grain-with the exception of pearl millet—can be consistently grown.6 Its massive and deep-penetrating roots are mainly responsible for this drought tolerance, but the plant has other drought-defying mechanisms as well. For instance, it apparently conserves moisture by reducing its transpiration when stressed (by rolling its leaves and possibly by closing the stomata to reduce evaporation) and it can turn down its metabolic processes and retreat into near dormancy until the return of the rains.

Third, sorghum is perhaps the world's most versatile crop. Some types are boiled like rice, some cracked like oats for porridge, some "malted" like barley for beer, some baked like wheat into flatbreads, and some popped like popcorn for snacks. A few types have sugary grains and are boiled in the green stage like sweet corn. The whole plant is often used as forage, hay, or silage. The stems of some types are used for building, fencing, weaving, broom-making, and firewood. The stems of other types yield sugar, syrup, and even liquid fuels for powering vehicles or cooking meals. The living plants are used for windbreaks, for cover crops, and for staking yams and other heavy climbers. The seeds are fed to poultry, cattle, and swine. On top of all that, sorghum promises to be a "living factory." Industrial alcohol, vegetable oil, adhesives, waxes, dyes, sizing for paper and cloth, and starches for lubricating oil-well drills are just some of the products that could be obtained.

Fourth, sorghum can be grown in innumerable ways. Most is produced under rain-fed conditions, some is irrigated, a little is grown by transplanting seedlings as is done with rice. Like sugarcane, it can also be ratooned (cut down and allowed to resprout from the roots) to

3  

Exceeding even maize silage, sugarcane, and maize grain. Heichel, 1976.

4  

At least some sorghums can survive standing in water for several weeks. Growth resumes when the water recedes.

5  

Information from D. Pasternak. Sorghum, however, is not as salt tolerant as several millets—selection and management will be needed to get good yields under saline conditions. See companion report. Saline Agriculture, for background on the importance of salt tolerance. (For a list of BOSTID publications, see page 377.)

6  

In one drought year the maize (corn) crop was so poor in Mitchell, South Dakota, that the annual "Corn Palace" had to be built out of sorghum. It was a humiliating comedown, but no maize could be found—only sorghum had survived.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement