Sorghum Diseases in India

Table 1. Diseases of sorghum in the Philippines, season of likely occurrence, relative importance,
and effect on yield. 1
Table 1. Diseases of sorghum in the Philippines, season of likely occurrence, relative importance,
and effect on yield. 1
Season of Relative Estimated
Disease occurrence 2
importance 3
yield loss 4 (%)
Sugarcane mosaic both minor 55
Sugarcane fiji both minor -
Bacterial leaf stripe both minor -
Bacterial stalk rot both minor -
Rust dry major 30
Tar spot both major 50
Gray leaf spot wet major -
Zonate leaf spot both minor -
Anthracnose/red rot wet minor -
Target leaf spot wet major 50
Rhizoctonia both major 75
Charcoal rot dry minor -
Head blight wet minor -
Head molds both major -
Seedling blight wet minor -
1. Source: Dalmacio (1982).
2. Maybe applicable in areas where thee are distinct wet and dry seasons. Wet season sowing is April to June. Dry
season sowing is October to December.
3. Based on frequency of observation, severity of disease, and potential for rapid spread.
4. From available experimental data.
Ilachora tar spot, gray leaf spot, head/grain
molds, rust, and Rhizoctonia banded leaf and
sheath blight (Table 1). Recent trends, however,
show the emerging importance and potential
threats of zonate and target leaf spots as well
as stalk rots. The incidence of these diseases
have been increasing in alarming proportions
on some commercial hybrids and varieties in
Southern and Central Mindanao (Exconde 1982).
Other diseases affecting sorghum in the Philippines
include sugarcane mosaic (red leaf disease),
charcoal and bacterial stalk rots, bacterial
stripe, anthracnose, sugarcane fiji disease, and
seedling/head blights (Table 1).
Experiments have demonstrated that sugarcane
mosaic can reduce yield by as much as
55%. Rust on sorghum in the Philippines may
decrease yields by 30%, target leaf spot by 22%,
Rhizoctonia disease by 75% (Karganilla and Elazegui
1973, Benigno and Vergara 1977), and tar
spot by 50%. During the 1978 wet season, severe
incidence of target leaf spot in the disease nursery
at Los Banos Central Experiment Station reduced
yield by 50%; in a contemporary trial,
under shade, tar spot prevented measurable
yields (Dalmacio 1980).
Screening for resistance to sorghum diseases
has been carried out by Dalmacio and his coworkers
since 1978. Sources of resistance to rust
and target leaf spot (201 and 198 lines, respectively)
seem to be more common (Table 2), as
compared to those of gray leaf spot (27 resistant
Table 2. Summary of results on the screening
for resistance to six sorghum diseases in the
Philippines. 1
Philippines. 1
Philippines. 1
Line/ variety
Tested Resistant
Disease (no.) (no.)
Gray leaf spot 2525 27
Rhizoctonia sheath blight 88 0
Rust 555 201
Tar spot 2268 51 2
Target leaf spot 2484 198
Head molds 50 0
1. Source: Dalmacio et al. (1981).
2. Includes two resistant lines (with a rating of 1) and
49 moderately resistant lines (with a rating of 2).
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