Sorghum Diseases in India

Sorghum Diseases in Mexico
J. Narro 1 , V.A. Betancourt 2 , and J.L Aguirre 3
Abstract
Grain sorghum (Sorghum tricolor) was introduced to Mexico in 1944; at that time, only openpollinated
varieties were sown. This crop became important in the early sixties; the first hybrids
were well accepted by farmers.
In the first years, the crop was relatively free of pests and diseases but by the end of the 1970s
this situation had changed, mainly in Mexico's two most important sorghum producing states:
Tamaulipas and Guanajuato. Biotic and abiotic diseases occurring in Mexico are grouped according
to importance, distribution, and prevalence in nine classes.
Information about control and research strategies to avoid further dissemination of the diseases
is presented herein.
Introduction
Grain sorghum [Sorghum bicolor (L.) Moench]
was introduced to Mexico in 1944 as a crop for
rainfed areas, which account for 80% of the total
agricultural area of Mexico. The first trials included
open-pollinated varieties; but introduction,
in the early sixties, of hybrid sorghums
greatly increased the crop's importance. Sorghum
was readily accepted by Mexican farmers
because of its high yield, wide adaptation, ease
of mechanization, and ease of incorporation into
different production systems.
At sorghum's introduction, serious problems
of diseases and pests did not occur, but now
they are present throughout many of the sorghum-growing
regions, and cause serious crop
losses in the two major sorghum-producing
states (Tamaulipas and Guanajuato). Head smut
was the first serious disease problem in Tamaulipas,
occurring in most commercial hybrids
in the late 1960s; in the mid 1970s, downy mildew
caused severe losses in the high-yielding
yellow endosperm hybrids. The disease impact
in Tamaulipas is critical, because 90% of the seed
and 25% of Mexico's total sorghum is produced
in this state. At present, crop losses occur in both
rainfed and irrigated areas.
Because of disease problems, sorghum research
was expanded and new hybrids, developed
by private companies and Mexico's
National Institute of the Forest, Agricultural,
and Livestock Research (INIFAP), replaced the
earlier hybrids. In 1972, Mexico's National Institute
of Agricultural Research, (which became
INIFAP in 1985), had released hybrids with good
yield and adaptation potential, but they became
susceptible, mainly to downy mildew.
Several years later, by a joint effort of
breeders and pathologists using new research
strategies, the hybrids RB 3030 and RB 3006
were released. These hybrids are adapted to
growing conditions in northern Tamaulipas,
Nuevo Leon, and Sinaloa. They exhibit good
levels of resistance to downy mildew (Peronosclerospora
sorghi) and head smut (Sporisorium
1. Agronomist, National Institute of Forest, Agricultural and Livestock Research (INIFAP) Apartado Postal 112, Celaya, Gto.,
Mexico.
2. Plant Breeder, Agricultural Research, S. of R.L., Colegio Militar 1124, Guadalajara, Jalisco, Mexico.
3. Plant Pathologist, National Insitute of Forest, Agricultural and Livestock Research (INIFAP), Apartado Postal 112, Rio Bravo,
Tamaulipas, Mexico.
Narro, J., Betancourt, V.A., and Aguirre, J.L 1992. Sorghum diseases in Mexico. Pages 75-84 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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