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Onion🧅
Allium cepa
タマネギ
A biennial (treated as annual in cultivation) native to Central Asia. The enlarged bulb is eaten and widely used in stir-fries, soups, and stews across both Western and Japanese cuisines. Characterized by pungency and sweetness from allyl sulfides, its sweetness intensifies when heated. Hokkaido is the largest domestic production area.
Identification Points
- ✓Cylindrical, hollow leaves (tubular leaves) are characteristic
- ✓Bulb is covered with dry, brown outer skin, globose to oblate
- ✓Tall flower stalk bears a spherical umbel of small white flowers
- ✓Cutting releases pungent volatile sulfur compounds
Habitat
Fields and farmland
Season
Autumn sowing: September–October, harvest the following May–June (spring sowing in Hokkaido)
Morphological TraitsAI-estimated, needs verification
Leaf arrangement
Alternate
Leaf type
Simple
Venation
Parallel
Leaf margin
Entire
Leaf shape
Linear
Growth form
Herb
Petal count
3 petals
Petal fusion
Free
Habitat
Cultivated
Leaf dissection
Undivided
Flower symmetry
Actinomorphic
Plant sex
Hermaphrodite
Aromatic
None
Phylogenetic Positionヒガンバナ科 →
Phylogenetic Position
Angiosperms > Monocots > Asparagales > Amaryllidaceae
Divergence Era
Late Cretaceous to Paleogene
Evolution Notes
The genus Allium, placed in Amaryllidaceae, evolved allyl sulfides as unique defensive compounds. These compounds produce the distinctive flavor and provide antibacterial and health benefits.
View on evolution timeline →Sources & References
AI-generated, needs verification