Onions

Foodplant / internal feeder
caterpillar of Acrolepiopsis assectella feeds within live stem of Allium

Foodplant / pathogen
colony of Botrytis dematiaceous anamorph of Botryotinia squamosa infects and damages live, white-flecked leaf (esp. towards tip) of Allium
Other: minor host/prey

Foodplant / pathogen
colony of Botrytis dematiaceous anamorph of Botrytis aclada infects and damages live leaf (base) of Allium

In Great Britain and/or Ireland:
Plant / resting place / within
puparium of Chromatomyia horticola may be found in leaf-mine (end of) of Allium

Foodplant / miner
larva of Delia platura mines leaf (lower parts) of Allium
Other: unusual host/prey

Foodplant / saprobe
Fusariella dematiaceous anamorph of Fusariella atrovirens is saprobic on Allium

Foodplant / nest
female of Hylaeus punctulatissima provisions nest with pollen of Allium

Foodplant / pathogen
Iris Yellow Spot virus infects and damages Allium

Foodplant / pathogen
Onion Yellow Dwarf virus infects and damages yellow, crinkled, flatened, twisted leaf of Allium

Plant / resting place / within
puparium of Phytomyza gymnostoma may be found in bulb of Allium
Other: sole host/prey

Foodplant / pathogen
colony of Phytophthora porri infects and damages live leaf of Allium
Remarks: season: (8-)10
Other: unusual host/prey

Foodplant / miner
larva of Scaptomyza pallida mines leaf of Allium
Remarks: season: spring, summer

Foodplant / pathogen
Sclerotium cepivorum infects and damages yellowed, wilting, died back leaf of Allium

Foodplant / saprobe
Sirexcipula coelomycetous anamorph of Sirexcipula kabatiana is saprobic on dead Allium