common whitlowgrass

organ parasitic mode stage note taxonomic group parasite
flower gall Eriophyidae Aceria drabae
leaf down Peronosporales Hyaloperonospora erophilae
leaf down Peronosporales Hyaloperonospora praecox
leaf gall Eriophyidae Cecidophyes borealis
leaf miner Curculionidae Ceutorhynchus minutus
leaf pustule Albuginales Albiginaceae Albugo candida
stem borer Curculionidae Ceutorhynchus pallidactylus
stem gall Curculionidae Ceutorhynchus hirtulus
root collar gall Plasmodiophorales Plasmodiophora brassicae
leaf vagrant Aphididae Aulacorthum circumflexum
leaf vagrant summer generation rarely Aphididae Utamphorophora humboldti
leaf vagrant Aphididae Aulacorthum solani
leaf vagrant Aphididae Macrosiphum euphorbiae
leaf vagrant Aphididae Myzus ornatus

Organ

the part of the plant that most conspicuously is hit by the parasite

all buds: both flower buds and leaf buds
flower: also inflorescence
leaf: also needle, phyllodium, petiole
leaf bud: also unfolding young leaf
fruit: also seed
root: also root stock, runners
root collar: also the lowest part of the stem
stem: also culm, the lower part of the peduncle, in grasses also leaf sheath
systemic: the entire above-ground plant.

PARASITIC MODE

borer: larva living internally, almost no outwards signs
down: 0.5-2 mm high fungal down
film: very thin cover of fungal tussue
gall: swelling and/or malformation
grazer: feeding at the outside of the plant
leaf spot discoloured, often ± necrotic, generally not galled, sign of a fungus infection
miner-borer: larve initially makes a mine, lives as a borer later
pustule: plug of fungal tissue, generally brown-black and < 2 mm
stripe: longitudinal line of fungal tissue in a grass leaf
vagrant: (aphids, mites) living freely on the plant, at higher densitiy causing malformations.

IMPORTANT

The host plant spectre of a parasite is rarely known exhaustively; this applies in particular at the species level. It is advisable therefore to check at least also the list of all parasites of this genus.

 

mod 26.xii.2017