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An isolate ofLaetisaria fuciformis in axenic culture did not produce toxic metabolites in concentrations sufficient to affect rats or sheep or mammalian cells in tissue culture, nor did it produce ergot alkaloids, paxilline or zearalenone in amounts detectable by ELISA. It did produce diffusable compound(s) inhibitory to a range of Gram-positive and-negative bacteria but not to the mould species tested.

After 6 weeks incubation on rice 2 strains of Fusarium crookwellense produced more zearalenone (6060–5010 mg/kg dry wt of culture) at ambient temperature (16–29°C) in daylight than at ambient temperature (18–23 °C) in darkness or at controlled temperatures of 11 °C, 20 °C or 25 °C in darkness. Yields at 25 °C were low. Incubation at 11 °C during the second 3 weeks incubation increased yields only when preliminary incubation had been at 25 °C. After 6 weeks incubation at controlled temperatures in darkness, 4 strains produced most zearalenone at 20 °C (2460-21 360 mg/kg), 1 strain at 11 °C (6570 mg/kg). Yields at a temperature oscillating daily from 10–20 °C were less than at 15 °C. One of the 5 strains produced appreciable amounts of a-zearalenol (1645 mg/kg at 20°C) and 2 of nivalenol (340 and 499 mg/kg at 20 °C).

Summary The taxonomy and distribution ofSchizoblastosporion starkeyihenricii has been discussed. In spite of the variable nature of the first strain isolated it seems most usually to be a stable entity, characterised by a method of vegetative reproduction intermediate between budding and fission. It does not produce ascospores or pseudomycelium or ferment sugars. A thin film may be formed on broth. Glucose and galactose are assimilated but not sucrose, maltose or lactose. Potassium nitrate is not used as a nitrogen source.S. starkeyi-henricii occurs most commonly, although rather sporadically, in cool, moist and acid soils in both hemispheres.