Sorghum Diseases in India

Sorghum Diseases in North America
R.A. Frederiksen 1 and R.R. Duncan 2
Abstract
Sorghum diseases are more important in the Central, Gulf Coast, and eastern growing regions of
the United States. Anthracnose, head blight, grain mold, and head smut remain as significant
constraints to production in some years in these regions. Diseases are rarely important in the Great
Plains, although the stalk rots and maize dwarf mosaic will affect production to some extent
annually.
Introduction
Sorghum diseases in the United States of America
were thoroughly reviewed by Edmunds and
Zummo (1975) and Frederiksen (1986). However,
these comprehensive treatises include no
data as to distribution or rank in importance of
each disease. Few attempts have been made to
estimate the extent of damage by pathogens on
sorghum in USA. Frederiksen (1980b) attempted
to do so on a global scale by rating each disease
as to its prevalence and importance by ecogeographic
regions. Consequently, a similar tabular
presentation of these estimates is made by
ecological zones. There are about five ecological
zones for sorghum production in USA. These, in
order of production, are the Great Plains, Central,
Gulf Coast, East Coast, and West (Fig. 1).
Over the past decade, U.S. sorghum area has
dropped from about 5.2 to about 4.3 million hectare.
Yields, however, have increased from an
average of 3.6 to about 4.3 t ha- 1 . While there is
variation in the types of diseases present in each
region (Table 1), much less variation is found
within than among these areas. Sorghum is
grown on the Great Plains (Texas, Panhandle
north to South Dakota), in part because of the
freedom of this area from most of the sorghum
diseases. Stalk rots and virus diseases are generally
present, but losses have not been substantial
(Doupnik and Frederiksen 1983). This is true, in
part, because of the development of hybrids
with tolerance to maize dwarf mosaic virus and
because of the development of machinery to mechanically
harvest lodged sorghum.
Sorghum downy mildew was widespread in
Kansas and Nebraska in 1987 (L. Claflin, personal
communication; Jensen et al. 1989). However,
yield losses on a statewide basis were
insignificant, and downy mildew is not expected
to be as prevalent in 1988 because the disease
has been present in Kansas for 20 years but in
only 2 years has it warranted concern. This suggests
that the environment for disease was unusually
favorable in 1987 and that the cultivars
used were susceptible to the pathotypes present.
Head smut occurs in some regions of Texas and
Kansas, more or less annually.
In the Central region (Missouri, Tennessee,
Illinois, and Kentucky) grain sorghum production
has increased over the past decade.
Diseases such as crazy top, sorghum downy mildew,
anthracnose, head blight, and grain mold
have at times been important. Anthracnose was
widely prevalent in parts of Missouri in 1986
and 1987 (J. Dale, and K. Cardwell, per-
1. Plant Pathologist, Texas Agricultural Experiment Station, Texas A&M Univeristy, College Station, TX 77843, USA.
2. Sorghum Breeder/Physiologist, University of Georgia, Georgia Experiment Station, Griffin, GA 30223, USA.
Frederiksen, R.A., and Duncan, R.R. 1992. Sorghum diseases in North America. Pages 85-88 in Sorghum and millets diseases: a
second world review, (de Milliano, W.A.J., Frederiksen, R.A., and Bengston, G.D., eds). Patancheru, A.P. 502 324, India: International
Crops Research Institute for the Semi-Arid Tropics.
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