Sorghum Diseases in India

1. Spray-inoculation of earheads with spore suspension
of Fusarium, Curvularia, and Phoma;
cover with paper bag.
2. Spray earheads with water; cover with paper
bag.
3. Leave earheads exposed to natural infection
during the rainy season.
Analysis of data showed these three methods
to be on par with each other.
Extensive testing of breeder's material and
germplasm, identified the following as resistant
on the basis of less reduction in field grade, less
reduction in threshed grain grade, maximum
germination (90-95%), and no loss in 100-mass.
The lines are SPV-126,312,346,351,386,472, and
2219 B; DMS1 B; MR 750 and 849; IS-3443, 3547,
14322, 10892, 14375, 14380, 24995, and 24996.
Some of these (IS-14375, 14380, 24995, 24996,
and 10892) are brown sorghums and were completely
free from molds. The lines IS-3443,24995,
and 249% have been utilized in developing
white-grained high-yielding sorghums, and the
developing generations were tested at Dharwad.
Efforts were made to identify effective fungicides
for grain mold control. It was found that
a combination of captan (0.2%) + aureofungin
(200 ppm) was best (Table 3), followed by mancozeb
(0.27) + captan (0.2%), and then thiram
(0.2%) + carbendazim (0.5%).
Charcoal rot
Extensive isolations from roots and stalks of diseased
plants collected during the rainy and postrainy
seasons yielded Macrophomina phaseolina,
Fusarium moniliforme, and other Fusarium spp,
separately and in mixtures. Most of the highyielding
varieties and hybrids presently cultivated
in India are highly susceptible. Grainyield
losses have been reported to range from 23
to 64% (Mughogho and Pande 1983, pp. 11-24)
and 15 to 55% (Anahosur and Patil 1983a). Plants
receiving 80 kg ha- 1 or more nitrogen fertilization
showed more disease than those receiving
from 40 to 80 kg ha" 1 or those receiving less
than 40 kg ha -1 (Anahosur et al. 1977). Further,
Avadhani et al. (1979), and Mote and Ramshe
(1980) reported similar results, i.e., excess nitrogen
predisposes the plants to susceptibility.
Effect of sowing date on charcoal rot incidence
in the rainy and postrainy seasons revealed that
rainy season sowings made in July suffered
Table 3. Experiments with six chemical control formulations for control of grain molds of CV
296 B (Average of four locations).
Treatment
Field Threshed-
grade
(1-5) 2
grain grade
(1-5) 2
Grain yield
(t ha -1 ) Rank 1
Captan 0.2% + aureofungin (200 ppm) 1.5 1.4 3.2 1
Mancozeb 0.2% + captan (0.2%) 1.6 1.5 3.1 2
Thiram (0.2%) + carbendazim (0.05%) 1.7 1.6 2.0 3
Captan (0.2%) 1.7 1.5 2.8 4
Carbendazim (0.1%) (Bavistin ® ) 1.8 1.6 2.8 5
Captafol (0.2%) (Difolatan ® ) 1.8 1.6 2.6 6
Control 4.2 3.7 2.5 7
1. Based on effectiveness in preventing grain yield losses.
2 Scored on a 1-5 scale: where 1 = least disease and 5 = most disease.
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