Plant Parasites of Europe

leafminers, galls and fungi

gallers on Dianthus

Dichotomous table for gallers on Dianthus

by Hans Roskam

1a On parts above ground => 2

1b Roots with small, ± spindle-shaped swellings which bear side roots. D. barbatus, caryophyllus: Meloidogyne hapla

= The cyst developing eelworms Heterodera schachtii and H. trifolii have been recorded on carnations

1c “Leafy gall” on root collar. D. barbatus, caryophyllus: Rhodococcus fascians

2a On flower buds and flowers => 9

2b On vegetative plant parts => 3

3a Malformations of shoot tips or locally defined swellings on leaves or stems => 6

3b Malformation of several plant organs => 4

4a Malformations caused by eelworms or mites => 5

4b Stem conspicuously stunted, leaves accumulated and strongly rolled downwards by activities of usually brown aphids. D. arenarius, barbatus, caryophyllus, deltoides, x lorberi, plumarius: Myzus certus

5a Complete plant disfigured; shoots shortened, leaves ± accumulated and discoloured. Leaf rosette enlarged. Organs not distinctly swollen. D. deltoides: Aceria dianthi

5b Shoots ± shortened, thickened, leaf blades clustered, in narrow-leafed species often partially broadened, swollen, especially at base, spongy, pale, undulate or wrinkled. On young single shoots rosette- or pineapple- tuft-like accumulated. “Pineapple disease”. Dianthus spp.: Ditylenchus dipsaci

6a Galls on stems or leaves => 7

6b Side shoots stunted; upper pair of leaves and the following lower pair shortened, converging and swollen. Containing a single yellowish larva. D. deltoides: Unidentified gall midge

7a The inducer is enclosed by the gall => 8

7b Yellowish pads on leaf blades countersunk on upperside, protruding on underside; on more narrow organs ± elongate bulges, bearing compact telia. Dianthus spp.: Puccinia arenariae

8a Stem distinctly shortened, slightly swollen. Galls glabrous or rough-walled. Leaves clustered, distorted and ± thickened. Containing a single larva in a large cavity. D. arenarius, carthusianorum, lusitanus, sylvestris: Caryocolum schleichi

8b Stem with swellings ± expanded, on one or on all sides, in the latter case accompanied by distortions, pale, wrinkled, spongy; similar swellings also on leaves penetrating from main venation into the leaf blade. Dianthus spp.: Ditylenchus dipsaci

9a Flowers conspicuously disfigured => 10

9b Flowers outwardly not conspicuously disfigured. Malformation usually limited to the temporarily swollen anthers, soon filled with a violet-tinged spore mass. Dianthus spp.: Microbotryum violaceum species complex

10a The swollen flower buds remain closed and are hardened. D. carthusianorum: Dasineura dianthi

10b Flower buds transformed into an often conspicuously swollen, ± globular to cone-shaped structure. Receptacle and adjacent organs ± temporarily swollen, later on filled with pale brown balls consisting of coarse-granular spores. Dianthus spp.: Thecaphora saponariae species complex

Last modified 16.iii.2020