Sexual and asexual developments

To induce cleistothecium formation, 6 d old conidia were plated in top agar at 1 × 10⁵ conidia/plate density and were incubated at 37 °C. After 24 h incubation, plates were sealed with Parafilm and samples were taken with a cork borer every day between 3–12 d of incubation, and cleistothecia/cm² were counted under a dissection microscope and cleistothecia/cm² values were calculated⁴⁶.

The conidiospore forming capabilities of the A. nidulans strains were determined as published by Vargas-Pérez et al.³³. Briefly, conidia (10⁵) of the mutant and control strains were spotted onto MNM agar plates as described above, and were incubated and were allowed to sporulate at 37 °C for 5 days. Conidia were harvested by washing, counted in a Burker chamber and spore numbers were expressed as number/cm² of colony surface. The areas of the colony surfaces were calculated using photographs.

To test the heat sensitivity of asexual spores, conidia were harvested from 6 days old colonies and suspended in physiological saline−0.01% Tween 80²⁴. Conidia in 10⁵/ml concentration were incubated at 50 °C for 10 min and, following that, were diluted and spread on MNM agar plates. The numbers of colonies representing successfully germinated conidia were counted after incubation for 2 days at 37 °C. Conidia without any heat treatment were used as reference. For viability test, conidia were stored at 4 °C and germination rates were determined after 3, 6 and 12 d storages as described above³².