organ parasitic mode stage note taxonomic group parasite
fruit gall Hypocreales Fusarium graminearum
leaf vagrant Aphididae Rhopalosiphum maidis
leaf vagrant summer generation Aphididae Sitobion fragariae
fruit gall Tilletiales Tilletia caries
fruit gall Tilletiales Tilletia controversa
flower gall Tilletiales Tilletia laevis
flower gall Ustilaginales Ustilago tritici
root gall Heteroderidae Heterodera avenae
leaf vagrant Aphididae Sipha elegans
leaf vagrant summer generation Aphididae Metopolophium dirhodum
leaf vagrant summer generation Aphididae Rhopalosiphum padi

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 19.vii.2018