common field-speedwell

organ parasitic mode stage note taxonomic group parasite
unknown borer larva Curculionidae Gymnetron rotundicolle
leaf leaf spot incertae sedis Discogloeum veronicae
leaf down Erysiphales Golovinomyces orontii
leaf down Erysiphales Podosphaera fuliginea
leaf down Peronosporales Peronospora agrestis
leaf leaf spot Entylomatales Entyloma veronicae
leaf miner Agromyzidae Phytomyza crassiseta
stem gall Plasmodiophorales Sorosphaera veronicae
leaf vagrant summer generation Aphididae Aphis frangulae
leaf vagrant summer generation Aphididae Brachycaudus helichrysi
stem vagrant Aphididae Dysaphis gallica

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 2.v.2019