High Power Binocular Microscope

In this investigation, survival of the teliosporogenous mycelia in 6, 7, 8 and 9 months old bunted kernels which had been infected artificially in the laboratory was examined. The sorus of each treatment was crashed in sterile distilled water and the suspension was placed on the surface of sterile distilled water in a completely randomized design with 5 replicates per treatment. Ten to 15 days later, floccose erected mycelia showing characteristics of the teliosporogenous mycelia appeared in the plates containing suspension that had been prepared from 6-8 months old infected kernels. Fifteen days after inoculation, colony numbers of teliosporogenous mycelia per plate were counted. Two- three weeks after transferring the mycelia to fresh YPDA, teliospores formed on this medium. After 4 weeks, mean teliospore formation on YPDA at 20°C and under laboratory conditions were 591.5 and 832 per plate, respectively. Also the teliosporogenous mycelial growth rate on YPDA at 20°C and room temperature were 2.31 and 1.85 mm day^-1, respectively. Fungus teliosporogenesis was studied in vitro and in situ by light, fluorescent and scanning electron microscope. During the teliosporogenesis, teliospore initials were formed in apical position in a lateral right-angled outgrowth of the teliosporogenous hyphae. The dikaryotic plasma was concentrated in the apical portion of the hypha. Fusion of nuclei occurred during the early enlargement of teliospore initial. The swelling, pyriform to spherical protoplast of the teliospore initial was delimited from the empty part of teliosporogenous hypha by a sheath, which was hyaline as observed by LM. The empty part of the hypha may form appendages. Underneath the sheath, the exosporium with ornamented surface and the smooth endosporium was deposited as seen in the mature teliospores. This is the first report of survival of the teliosporogenous mycelia in the Karnal bunt infected kernels after several months of storage. This may be of great importance in pathogen survival and disease epidemiology.


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