My problem is related with ITS primer .Previously i had no problem but from fews days bands on 1% agarose gel sometimes show smears, sometimes multiple bands and sometimes increase in amplicon size. I checked all the reagents and conitions ,and found when used i use buffer and mgcl2 from others lab (and other reagents own) , i got no problem .But when i use either buffer or mgcl2 of own i got above problems