Dichotomous table for gallers on Gladiolus
by Hans Roskam
1a On leaves and scapes => 4
1b On roots or tubers => 2
2a Malformations on tubers => 3
2b Roots with nodular swellings. G. x gandavensis, x hybridus: Meloidogyne hapla
3a Bulge-like galls on tuber surface => 4
3b Yellow-brown large “leafy galls”, tuber- or scale-shaped accumulations at the base of the tuber, up to 40 mm in cross section. Gladiolus spp.: Rhodococcus fascians
4a Blackish, partially yellow margined bulge-like swellings on leaves, stems and tubers. Releasing a dark brown powder consisting of spore balls after breaking open. G. imbricatus, italicus, palustris: Urocystis gladiolicola
4b Less severely infected tubers that are partially destroyed internally develop only some variously bleached and curved leaves, bearing ± oblong spindle-shaped, spongy bulges. Gladiolus spp.: Ditylenchus dipsaci