Efficacy of seed treaters on the germination of ergot (Claviceps purpurea (Fr.) Tul.) sclerotia and stroma formation
Šiauliai University, Višinskio 19, Šiauliai, 77156, Lithuania; e-mail: OIKOS@fm.su.lt
Abstract:
The effects of the fungicidal seed treaters Baitan-Universal 19,5 WS and Divident Star 036 FS, Divident Star with bioactivator Penergetic-p and Penac as well as biopesticide Bionature R2000 applied alone on the germination of ergot (Claviceps purpurea (Fr.) Tul.) sclerotia and stroma formation were studied in the laboratory and field conditions in 2004 and 2005. Rye (Secale cereale L.) seed, contaminated with ergot sclerotia, was used for the tests. The rates recommended for rye seed treatment were applied.In the experiments 45.5–79.0% of untreated sclerotia germinated, and each sclerotiumformed on average 3.7–7.5 stromas. The fungicidal seed treaters tested inhibited and delayed sclerotia germination. In the laboratory conditions Baitan-Universal and Divident Star gave 86.1-100% suppression of sclerotia germination and 90.1–100% of stroma formation. Under the field conditions this suppression was lower: 46.2–68.8 % and 57.4–84.3%, respectively. Bioactivators did not exert any effect on sclerotia germination and stroma formation in the laboratory conditions, but they increased sclerotia germination by 3.3–15.3% and stroma formation by 19.5–96.0 units per 100 sclerotia in the field conditions. The biopesticide Bionature significantly inhibited stroma formation only in 2005.
Key words:
Claviceps purpurea, ergot, sclerotia, seed treaters, stroma