Mechanisms of heat and drought resistance in grain sorghum and methods of measurement

It is also evident that there is a great deal of further research opportunity for study of the drought resistance of the thousands of sorghum types as exemplified in the world collection. We have only touched on the many aspects of drought resistance, but an attempt has been made to emphasize some basic principles and practical methods of measurement. In order for plant breeders to make selections of many of the traits mentioned, specific measurements and tests must be made. An analogy is not too far from improvements made in nutritional and baking quality of wheat, where several factors were first identified and then combined for maximum benefit. They could not be seen with the eye, and selection pressures were obtained from laboratory tests. Sorghum drought resistance improvement should make greater progress if first avoidance and tolerance mechanisms are identified with many sorghums grown in different environments. Once this is done, decisions can be made as to the combination of factors most desirable for maximum yield in the average environment of the particular location.