Sorghum Diseases in India

Guiragossian: Farmers and children in Rwanda
consume honey dew (ergot) at early stages and
they claim that people who consume a lot of
honey dew get a bad smell in their mouth originating
from their stomach. Would you know
what causes the bad smell?
Mantle: Millet ergot honey dew has a distinctive
aroma which is certainly attractive to flies and
other insects in Africa. These volatiles may be
more readily released in the stomach. They are
typical C. fusiformis alkaloids, but probably not
enough in quantity to cause gastric disturbances
or other malaise.
Laing: Do the alkaloids in ergot of sorghum and
millet act as human contraceptives?
Mantle: There is evidence that the alkaloids of
the ergot of millet are active with respect to human
conception or pregnancy From first principles,
it may be deducted that they would not be
particularly active. It is possible, that ergot of
sorghum in Africa is no significant hazard to
human health nor do the alkaloids have useful
biological properties.
Adipala: Does Xanthomonas campestris on pearl
millet attack other millets (like finger millet) in
India? Do you have intercropping of pearl millet
and finger millet, and if so, what is the effect on
the incidence of Xanthomonas campestris?
Balasubramanian: We do not have X. campestris
on pearl millet in India, nor do we intercrop
pearl millet and finger millet.
Qhobela: The Xanthomonas campestris pathovar
that infects pearl millet, will also infect proso
millet but it is not a pathogen on finger millet or
Japanese millet.
Balasubramanian (to Claflin): In the photograph
of gels you showed, are the bands isozymes
or proteins?
Claflin: The slide was a protein profile of Pseudomonas
avenue, P. andropogonis, and the pearl millet
isolate (P. avenae) determined by a SDS-page
gel.
Mughogho: During your survey in Nigeria,
were you able to identify the bacterium that
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causes the yellow leaf blotch of sorghum first
reported by N. Zummo?
Claflin: Two predominant bacterial-colony types
were reported by Zummo as the cause of yellow-leaf
blotch. We identified the yellow colony
type as Erwinia herbicola, a common saprophyte
on plant tissue. The white colony type was identified
as a pseudomonad, as reported by Zummo,
but our culture was lost while attempting to
identify the species.
King: On the survey you mentioned in Nigeria,
in which almost all pearl millet plants had bacterial
symptoms, would you be able to assess the
possible damage to yields?
Claflin: At the time of the survey, the pearl millet
plants were at the flowering stage of development
and it was unknown if the bacterial lesions
continued to progress. To say that this bacterial
stripe affected yields would be only conjecture
on my part.
Teyssandier: Could you tell me if it is possible
to distinguish symptoms produced by Pseudomonas
andropogonis from those produced by
Pseudomonas alboprecipitans on sorghum?
Claflin: I am unable to detect any difference in
symptoms produced by P andropogonis and P
avenae (Syn. P. alboprecipitans). They are easily
distinguished by physiological, biological, and
serological tests.
de Milliano: How important are bacertia on sorghum
in Lesotho?
Claflin: A high incidence of bacterial streak was
observed in Lesotho, particularly in forage sorghums.
It is unknown if bacterial diseases are
involved in sorghum yield reductions in Lesotho.
Only Xanthomonas campestris pv holcicola
was isolated from sorghum tissue.
Balasubramanian: Will the airgun inoculation
technique damage ceils before the virus enters?
Is it not an unnatural method to introduce the
virus into sorghum plants in the field?
Toler: The airgun device, if used at the right
pressure, will not kill cells on the leaf. The carborundum
particles tear holes in the cell wall;