BBCH-scale (bulb vegetable)
In biology, the BBCH-scale for bulb vegetables describes the phenological development of bulb vegetable plants, such as onion, leek, garlic and shallot, using the BBCH-scale.
The phenological growth stages and BBCH-identification keys of bulb vegetables are:
| Growth stage | Code (2-digit) | Code (3-digit) | Description |
|---|---|---|---|
| 0: Germination | 00 | 000 | Dry seed,1 dormant bulb2 |
| 01 | 000 | Beginning of seed imbibition1 | |
| 03 | 003 | Seed imbibition complete1 | |
| 05 | 005 | Radicle emerged from seed.1 Roots appearing2 | |
| 07 | 007 | Cotyledon breaking through seed coat1 | |
| 09 | 009 | Emergence: cotyledon breaks through soil surface.1 Green shoot visible2 | |
| 010 | Cotyledon visible as hook1 | ||
| 011 | Hook stage: hooked cotyledon green1 | ||
| 012 | Whip stage: cotyledon has whip-like form1 | ||
| 1: Leaf development (Main shoot) | 10 | 100 | Advanced whip stage: whip begins to die off1 |
| 11 | 101 | First leaf (> 3 cm) clearly visible | |
| 12 | 102 | 2nd leaf (> 3 cm) clearly visible | |
| 13 | 103 | 3rd leaf (> 3 cm) | |
| 1 . | 10 . | Stages continuous till . . . | |
| 19 | 109 | 9 or more leaves clearly visible | |
| 4: Development of harvestable vegetative plant parts | 41 | 401 | Leaf bases begin to thicken or extend |
| 43 | 403 | 30% of the expected bulb or shaft diameter reached | |
| 45 | 405 | 50% of the expected bulb or shaft diameter reached | |
| 47 | 407 | Bolting begins; in 10% of the plants leaves bent over3 70% of the expected shaft length and diameter reached4 | |
| 48 | 408 | Leaves bent over in 50% of plants3 | |
| 49 | 409 | Leaves dead, bulb top dry; dormancy3
Growth complete; length and stem diameter typical for variety reached4 | |
| 5: Inflorescence emergence | 51 | 501 | Onion bulb begins to elongate |
| 53 | 503 | 30% of the expected length of flower stem reached | |
| 55 | 505 | Flower stem at full length; sheath closed | |
| 57 | 507 | Sheath burst open | |
| 59 | 509 | First flower petals visible; flowers still closed | |
| 6: Flowering | 60 | 600 | First flowers open (sporadically) |
| 61 | 601 | Beginning of flowering: 10% of flowers open | |
| 62 | 602 | 20% of flowers open | |
| 63 | 603 | 30% of flowers open | |
| 64 | 604 | 40% of flowers open | |
| 65 | 605 | Full flowering: 50% of flowers open | |
| 67 | 607 | Flowering finishing: 70% of petals fallen or dry | |
| 69 | 609 | End of flowering | |
| 7: Development of fruit | 71 | 701 | First capsules formed |
| 72 | 702 | 20% of capsules formed | |
| 73 | 703 | 30% of capsules formed | |
| 74 | 704 | 40% of capsules formed | |
| 75 | 705 | 50% of capsules formed | |
| 76 | 706 | 60% of capsules formed | |
| 77 | 707 | 70% of capsules formed | |
| 78 | 708 | 80% of capsules formed | |
| 79 | 709 | Capsule development complete; seeds pale | |
| 8: Ripening of fruit and seed | 81 | 801 | Beginning of ripening: 10% of capsules ripe |
| 85 | 805 | First capsules bursting | |
| 89 | 809 | Fully ripe: seeds black and hard | |
| 9: Senescence | 92 | 902 | Leaves and shoots beginning to discolour |
| 95 | 905 | 50% of leaves yellow or dead | |
| 97 | 907 | Plants or above ground parts dead | |
| 99 | 909 | Harvested product (seeds) | |
1 Seed sown
2 Onion sets, shallot and garlic
3 For onions, garlic
4 For leek
References
Feller, C.; H. Bleiholder; L. Buhr; H. Hack; M. Hess; R. Klose; U. Meier; R. Stauss; T. van den Boom; E. Weber (1995). "Phänologische Entwicklungsstadien von Gemüsepflanzen: I. Zwiebel-, Wurzel-, Knollen- und Blattgemüse. Nachrichtenbl. Deut". Pflanzenschutzd. 47: 193–206.