Smut
Moesziomyces penicillariae (Bref.) Vanky
Symptoms: Immature, green sori larger than the seed
develop on panicles during grain fill. A single sorus develops
per floret. As grain matures, sori change in color from green
to dark brown. Sori are filled with dark teliospores.
Pathogen and disease characteristics: Chestnut brown
to black-brown sporeballs are composed of 200 to 1,400 aggregated
yellowish brown globose to subglobose teliospores. Teliospores
germinate to produce promycelia with basidiospores and sporidia
(Subba Rao and Thakur 1983). Infection
occurs when sporidia suspended in rain or dew infiltrate into
the boot (Wilson 1995). Aerial populations
of sporidia are greatest when minimum and maximum temperatures
range between approximately 21 and 31 °C and maximum relative
humidity is greater than 80 percent (Kousik
et al. 1988).
Host range: Pearl millet.
Geographic distribution: United States (Wells
et al. 1963), India, Zimbabwe, Senegal, Chad, Niger, Nigeria,
Malawi (Wiehe 1953, Saccas
1954, King 1970, Jouan
and Delassus 1971, Rachie and Majmudar
1980), and Tanzania (Mbwaga et al.
1993). Also Zambia, Sudan, Cameroon, Burkina Faso, Ghana,
Mali (S.B. King, personal communication, 1995).
Nomenclature discrepancies: Synonyms: Tolyposporium
penicillariae Bref. (Vanky 1977),
Tolyposporium senegalense Speng.
Considerable confusion exists in the literature concerning
smut of pearl millet. For further details, see "Questionable
or poorly described diseases of pearl millet reported in the literature."
Seed transmission: Seed may be infested with teliospore
balls, but infection does not take place through seedlings (Bhatt 1946). Teliospores may remain viable
in the soil, where basidiospores and sporidia may be produced
(Patel et al. 1959).
Primary citations: As indicated above.
United States
Department of Agriculture
Agricultural
Research Service
The material on this page is in the public
domain.
Original posting: June 5, 1999.
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