hop trefoil

organ parasitic mode stage note taxonomic group parasite
flower gall doubtful Apionidae Protapion apricans
flower borer Apionidae Protapion nigritarse
unknown borer larva Apionidae Protapion schoenherri
systemic borer Anguinidae Ditylenchus dipsaci
fruit gall Curculionidae Tychius junceus
fruit gall Curculionidae Tychius pusillus
leaf bud gall Apionidae Protapion filirostre
leaf down Erysiphales Erysiphe trifoliorum
leaf down Peronosporales Peronospora trifolii-arvensis
leaf gall Cecidomyiidae Dasineura trifolii
leaf miner Agromyzidae Agromyza nana
leaf miner Agromyzidae Liriomyza congesta
leaf miner Agromyzidae Phytomyza brischkei
leaf miner Gracillariidae Phyllonorycter medicaginella
leaf pustule aecia uredinia telia Pucciniales Uromyces fallens
leaf pustule aecia telia Pucciniales Uromyces minor
leaf pustule uredinia telia Pucciniales Uromyces jaapianus
leaf pustule uredinia telia Pucciniales Uromyces striatus
leaf pustule telia Pucciniales Uromyces flectens
leaf pustule telia Pucciniales Uromyces trifolii
root collar gall Apionidae Catapion pubescens
stem vagrant Aphididae Acyrthosiphon pisum
stem vagrant Aphididae Aphis craccivora


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.


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.


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.iv.2019