Author
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Goates, Blair |
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Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only Publication Acceptance Date: 4/1/2005 Publication Date: 7/1/2005 Citation: Goates, B. 2005. Durability of secondary sporidia of floret infecting tilletia species: implications for epidemiology.. American Phytopathological Society Annual Meeting. Interpretive Summary: Technical Abstract: Secondary sporidia resulting from germinating teliospores of some Tilletia species cause local infection of wheat, rice and rye grass florets leading to disease in the seed. Secondary sporidia are considered to be relatively fragile and short lived. To examine this, secondary sporidia from potato dextrose agar or water agar cultures of T. horrida, T. indica, T. walkeri, and the seedling infecting species T. tritici were deposited via natural liberation onto lids of Petri dishes and were air dried and maintained at 10-20% RH at 20-22C, and at 40-50% RH at 18C. After various time periods lids were inverted over fresh PDA to determine viability. Dried sporidia had the ability to regenerate after 30 days at 10-20% RH and 60 days at 40-50% RH. The upper limits of regeneration were not determined. Commonly, 18 hours after lids containing dried sporidia were inverted over PDA, newly produced secondary sporidia were present on the agar and had produced hyphae capable of infecting plants. There was no difference in viability of sporidia dried rapidly at 10% RH or dried over 10 hours. If similar durability and regeneration occurs in field environments, sporidia could survive for extensive periods under dry conditions and then rapidly regenerate and infect plants under humid rainy conditions normally associated with the diseases. |
