Time-Dependent Sporulation, Conidial Size and Germ Tube Formation in Alternaria tenuissima (Kunze ex Pers.) Wiltshire on Different Media

Time!dependent sporulation\ conidial size and germ tube formation in Alternaria tenuissima "Kunze ex Pers[# Wiltshire on di}erent media were studied[ The results indicate that maximum number of _rst spore was formed on potato dextrose agar "PDA# and new leaf extract of pigeon pea followed by old leaf extract of pigeon pea and distilled water "DW#[ The sporulation was relatively poor on other media[ The maximum number of spores in a chain were produced on PDA and albumen 9[8) sodium citrate[ Only one spore was seen in DW[ Accord! ing to time!dependent sporulation\ the media were divided into three categories] on some media the _rst spore was formed in 07 h\ in another group it took 29 25 h and in the third group the _rst conidium was formed after 39 h[ Four germ tubes were commonly formed on most of the media[ The largest conidia were observed on potato dextrose and the smallest ones were seen on DW