organ parasitic mode stage note taxonomic group parasite
leaf down Erysiphales Golovinomyces tabaci
leaf miner Agromyzidae Chromatomyia horticola
leaf vagrant summer generation Aphididae Brachycaudus helichrysi
leaf vagrant Aphididae Aphis gossypii
leaf vagrant summer generation Aphididae Aphis fabae fabae
leaf down Erysiphales Golovinomyces orontii
leaf down Erysiphales Golovinomyces spadiceus
leaf down Erysiphales Neoërysiphe cumminsiana
leaf leaf spot Entylomatales Entyloma dahliae
leaf leaf spot Pleosporales Alternaria carolinaeana
leaf gall Aphelenchoididae Aphelenchoides fragariae
leaf miner Agromyzidae Chromatomyia syngenesiae
leaf miner Agromyzidae Liriomyza bryoniae
leaf miner Agromyzidae Liriomyza strigata
leaf miner Agromyzidae Liriomyza trifolii
leaf vagrant summer generation Aphididae Aphis fabae
stem gall Rhizobiales Agrobacterium tumefaciens
root collar gall Actinomycetales Rhodococcus fascians
root borer Anguinidae Ditylenchus destructor
root gall Meloidogynidae Meloidogyne hapla
leaf vagrant Aphididae Macrosiphum euphorbiae
leaf vagrant Aphididae Aulacorthum solani

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 17.iii.2019