violaceum is able to establish populations of its haploid yeastlike sporidial stage in the nectar of healthy plants.
The yeast or sporidial stage of this pathogen itself was found in all of the diseased sites, and in four of the five healthy sites with consistent presence in H2, a healthy population near to a diseased population, D2 (Fig.
Inoculation for artificial epidemics: Fresh sporidial suspension derived from Teliospores populations obtained from each one year old sample preliminary considered an isolate, collected from various vicinities was used, and inoculum was prepared according to the method of Bonde et al.
This process supplemented much to the discharge and liberation of the secondary sporidia which were later on incubated at 20degC for 20 days for mass multiplication of sporidial suspension.
1ml (10,000 sporidia /ml) of allantoid sporidial suspension was injected by syringe method, at boot stage, in to boot cavity of eight to ten spikes/entry of each accession for each isolate as this technique gives maximum percentage of infection (Chona et al.
transfers were made from uncontaminated areas of 12 cultures and were maintained individually.
Second, 25 replicated genotypes were transplanted to a healthy population and artificially inoculated in the rosette leaves with a sporidial suspension of M.
Each fungal isolate was a result of a combination of two sporidial cultures of opposite mating type that came from a single teliospore.
Flowering plants used as disease source plants were inoculated as 8-d-old seedlings by being soaked overnight at 17 [degrees] C in a sporidial
suspension of crossed strains of opposite mating type of U.
Six different sporidial
isolates were used to produce three distinct dikaryon types, A (31 x 36), C (28 x 29), and D (19 x 14) previously used by Alexander (1989).
Single sporidial lines of each mating type were isolated from six populations of U.
Seedlings of Silene alba were soaked in a mixed sporidial suspension for 48 h and their infection rate was determined as above.