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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):Tilletia oplismeni-cristati Patouillard & Hariot ex Durán & G.W. Fischer forms similar sori, but its ustilospores are unevenly ornamented with small, discrete, dense clusters of narrow warts that at low power give the impression of raised blocks c. 3-5 µm wide. Melanotaenium brachiariae Viégas, a South American species, forms sori as black, flat spots in leaves, and has smooth spores smaller than those of the Tilletia species. Shetty & Safeeulla (1981) studied ustilospore germination, nuclear behaviour and survival. They found that freshly collected spores were incapable of germination, but after 3 months at room temperature or 25 days at 5°C germination occurred at temperatures between 15 and 25°, optimum 18-21°C. Spores survived at least 9 months at room temperature, 18 months in a refrigerator, but were killed by 3 days at 40°C. Meiotic division occurred in the ustilospore, the daughter nuclei passed into a stout, non-septate basidium, continued to divide and eventually migrated into 40-45 uninucleate acicular basidiospores formed apically. The basidiospores later became binucleate but never conjugated with each other. The fungus was regarded as homothallic. Durán (1972) reported a similar germination pattern. The status of Tilletia apludae Thirum. & Mishra requires further investigation. It has been placed in synonymy with T. vittata (Durán & Fischer, 1961) with which it has many similarities especially in ustilospore characters, but its sori lack the distinctive form and covering of T. vittata and its host Apluda is in tribe Andropogoneae not Paniceae. No cross-infection studies have been reported; nor have they for T. panici Mundkur, but this shows good correspondence in all characters and is on Paniceae (20, 179; 29, 124).
 
Description type:Non-original description 
Description:Tilletia vittata (Berk.) Mundkur, Transactions of the British Mycological Society 24: 312, 1940 (1941).
Ustilago vittata Berk., Gdnrs' Chron. 1853: 148, 1853.
Tilletia vittata (Berk.) Mundkur var. burmannii Mishra, Mycologia 49: 260, 1957.
Neovossia vittata (Berk.) Shetty & Safeeulla, Indian Phytopath. 33: 399, 1980 (1981).
Tilletia panici Mundkur, Trans. Br. mycol. Soc. 24: 317, 1940 (1941).
Sori in scattered ovaries of the inflorescence, greyish brown, emerging from the glumes as cylindrical, often slightly curved, bodies, bluntly pointed at the apex which sometimes shows traces of a stigma, variable in length (c. 5-25 mm) and 1-2 mm broad. Sorus covering of host tissue, its outer surface with long, hyaline, appressed hairs directed towards the sorus apex; eventually splitting longitudinally to expose the spore mass. Spore mass black, powdery, composed of ustilospores intermixed with sterile cells. Sterile cells globose to subglobose or occasionally slightly angular, hyaline, tinted brownish-yellow, 7-26(mean 15,4) µm diam., most 16-22 µm diam. but smaller ones, c. 10 µm diam., often forming small clumps, also present. Ustilospores globose to subglobose, dark yellowish-brown, 14-25 (mean 18,5) µm diam., walls approximately 1 µm thick,densely and evenly ornamented with bluntly conical to columnar processes 0,5-1,5 µm long and up to 1 µm wide at the base.
Hosts: Oplismenus species, including O. burmannii, O. compositus, O. setarius, O. undulatifolius.
Disease: Ovary smut of Oplismenus. Usually only about 30% of the ovaries in an inflorescence are infected.
Geographical distribution: Africa: Kenya; Asia: India (Andhra Pradesh, Bihar, Uttar Pradesh, West Bengal; 72,
5629; Karnataka, Shetty & Safeeulla, 1981); Australasia: Australia (Qld); North America: Mexico (Durán, 1972).
Physiological specialization: Mishra (1957) observed that in mixed populations of Oplismenus compositus and O. burmannii, cross infections by the smuts on these hosts did not occur. This suggests a degree of physiologic specialization when the smuts are regarded as synonymous.
Transmission: The dusty spore mass is presumably dispersed by air currents; any seed contamination that occurs is unlikely to be important because infection is not systemic. Shetty & Safeeulla (1981) obtained infection by spraying unopened flowers with basidiosporal suspensions made from agar cultures.
Literature: Shetty & Safeeulla, Indian Phytopathology 33: 399-404, 1981; Mishra, Mycologia 49: 260, 1957; Durán, Canadian Journal of Botany 50: 2569-2573, 1972; Durán & Fischer, The Genus Tilletia, Pullman, Washington State University, 1961.

 
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