Cereal growth staging scales

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Cereal growth staging scales attempt to objectively measure the growth of cereals.

BBCH-scale (cereals)[edit]

In agronomy, the BBCH-scale for cereals' describes the phenological development of cereals using the BBCH-scale.

The phenological growth stages and BBCH-identification keys of cereals are:

Growth stage Code Description
0: Germination 00 Dry seed (caryopsis)
01 Beginning of seed imbibition
03 Seed imbibition complete
05 Radicle emerged from caryopsis
06 Radicle elongated, root hairs and/or side roots visible
07 Coleoptile emerged from caryopsis
09 Emergence: coleoptile penetrates soil surface (cracking stage)
1: Leaf development1, 2 10 First leaf through coleoptile
11 First leaf unfolded
12 2 leaves unfolded
13 3 leaves unfolded
1 . Stages continuous till . . .
19 9 or more leaves unfolded
2: Tillering3 20 No tillers
21 Beginning of tillering: first tiller detectable
22 2 tillers detectable
23 3 tillers detectable
2 . Stages continuous till . . .
29 End of tillering. Maximum no. of tillers detectable
3: Stem elongation 30 Beginning of stem elongation: pseudostem and tillers erect, first internode begins to elongate, top of inflorescence at least 1 cm above tillering node
31 First node at least 1 cm above tillering node
32 Node 2 at least 2 cm above node 1
33 Node 3 at least 2 cm above node 2
3 . Stages continuous till . . .
37 Flag leaf just visible, still rolled
39 Flag leaf stage: flag leaf fully unrolled, ligule just visible
4: Booting 41 Early boot stage: flag leaf sheath extending
43 Mid boot stage: flag leaf sheath just visibly swollen
45 Late boot stage: flag leaf sheath swollen
47 Flag leaf sheath opening
49 First awns visible (in awned forms only)
5: Inflorescence emergence, heading 51 Beginning of heading: tip of inflorescence emerged from sheath, first spikelet just visible
52 20% of inflorescence emerged
53 30% of inflorescence emerged
54 40% of inflorescence emerged
55 Middle of heading: half of inflorescence emerged
56 60% of inflorescence emerged
57 70% of inflorescence emerged
58 80% of inflorescence emerged
59 End of heading: inflorescence fully emerged
6: Flowering, anthesis 61 Beginning of flowering: first anthers visible
65 Full flowering: 50% of anthers mature
69 End of flowering: all spikelets have completed flowering but some dehydrated anthers may remain
7: Development of fruit 71 Watery ripe: first grains have reached half their final size
73 Early milk
75 Medium milk: grain content milky, grains reached final size,

still green

77 Late milk
8: Ripening 83 Early dough
85 Soft dough: grain content soft but dry. Fingernail impression not held
87 Hard dough: grain content solid. Fingernail impression held
89 Fully ripe: grain hard, difficult to divide with thumbnail
9: Senescence 92 Over-ripe: grain very hard, cannot be dented by thumbnail
93 Grains loosening in day-time
97 Plant dead and collapsing
99 Harvested product
  • 1 A leaf is unfolded when its ligule is visible or the tip of the next leaf is visible
  • 2 Tillering or stem elongation may occur earlier than stage 13; in this case continue

with stages 21

  • 3 If stem elongation begins before the end of tillering continue with stage 30

Feekes scale[edit]

The Feekes scale is a system used by agronomists to identify the growth and development of cereal crops. The Feekes scale is more widely used in the United States[1] than other similar and more descriptive[2][3] scales such as the Zadoks scale or the BBCH scale. The scale was originally described in 1941[4] and, like other scales of crop development, is useful in planning management strategies that incorporate plant growth information for the use of pesticides and fertilizers to avoid damaging the crop and/or maximize crop yield.

Cereal growth stages using the Feekes scale[4]
Stage Description
Tillering
1 One shoot (number of leaves can be added), first leaf through coleoptile.
2 Beginning of tillering; main shoot and one tiller.
3 Tillers formed; leaves often twisted spirally. Main shoot and six tillers. In some varieties of winter wheat, plant may be “creeping,” or prostrate.
4 Beginning of the erection of the pseudo-stem; leaf sheaths beginning to lengthen.
5 Pseudo-stem (formed by sheaths of leaves) strongly erected.
Stem Extension
6 First node of stem visible at base of shoot.
7 Second node of stem formed; next-to-last leaf just visible.
8 Flag leaf (last leaf) visible but still rolled up; ear beginning to swell.
9 Ligule of flag leaf just visible.
10 Sheath of flag leaf completely grown out; ear swollen but not yet visible.
Heading
10.1 First spikelet of head just visible.
10.2 One-quarter of heading process completed.
10.3 Half of heading process completed.
10.4 Three-quarters of heading process completed.
10.5 All heads out of sheath.
Flowering
10.51 Beginning of flowering.
10.52 Flowering complete to top of head.
10.53 Flowering completed at base of head.
10.54 Flowering completed; kernel watery ripe.
Ripening
11.1 Milky ripe.
11.2 Mealy ripe; contents of kernel soft but dry. Soft dough.
11.3 Kernel hard (difficult to divide with thumbnail).
11.4 Ripe for cutting. Straw dead.

Zadoks scale[edit]

The Zadoks scale is a cereal development scale proposed by the Dutch phytopathologist Jan C. Zadoks that is widely used in cereal research and agriculture. Knowing the stages of development of a crop is critical in many management decisions that growers make. They are represented on a scale from 10 to 92. For example, in some countries, nitrogen and herbicide applications must be completed during the tillering stage. In France, the recommendation for the first nitrogen application on wheat is 6 weeks before Z30, with the second application on Z30. Wheat growth regulators are typically applied at Z30. Disease control is most critical in the stem extension and heading stage (Z31, Z32, Z35), in particular as soon as the flag leaf is out (Z37). The crop is also more sensitive to heat or frost at some stages than others (for example, during the meiosis stage the crop is very sensitive to low temperature). Knowing the growth stage of the crop when checking for problems is essential for deciding which control measures should be followed.

Examples of typical stages

  • during tillering
    • Z10: one leaf
    • Z21: tillering begins
  • during stem extension
    • Z30: ear is one centimeter long in wheat
    • Z31: first node visible
    • Z32: second node visible
    • Z37: flag leaf
  • during heading
    • Z55: the head is 1/2 emerged.
  • during ripening
    • Z92: grains are ripe
Comparison of growth stage scales
Zadok

Scale

Feekes

Scale

Haun

Scale

Description
Germination
00 Dry seed
01 Start of imbibition
03 Imbibition complete
05 Radicle emerged from seed
07 Coleoptile emerged from seed
09 0.0 Leaf just at coleoptile tip
Seedling growth
10 1 First leaf through coleoptile
11 1.+ First leaf unfolded
12 1.+ 2 leaves unfolded
13 2.+ 3 leaves unfolded
14 3.+ 4 leaves unfolded
15 4.+ 5 leaves unfolded
16 5.+ 6 leaves unfolded
17 6.+ 7 leaves unfolded
18 7.+ 8 leaves unfolded
19 9 or more leaves unfolded
Tillering
20 Main shoot only
21 2 Main shoot and 1 tiller
22 Main shoot and 2 tillers
23 Main shoot and 3 tillers
24 Main shoot and 4 tillers
25 Main shoot and 5 tillers
26 3 Main shoot and 6 tillers
27 Main shoot and 7 tillers
28 Main shoot and 8 tillers
29 Main shoot and 9 or more tillers
Stem Elongation
30 4-5 Pseudo stem erection
31 6 1st node detectable
32 7 2nd node detectable
33 3rd node detectable
34 4th node detectable
35 5th node detectable
36 6th node detectable
37 8 Flag leaf just visible
39 9 Flag leaf ligule/collar just visible
Booting
40 -
41 8-9 Flag leaf sheath extending
45 10 9.2 Boots just swollen
47 Flag leaf sheath opening
49 10.1 First awns visible
Inflorescence emergence
50 10.1 10.2 First spikelet of inflorescence visible
53 10.2 1/4 of inflorescence emerged
55 10.3 10.5 1/2 of inflorescence emerged
57 10.4 10.7 3/4 of inflorescence emerged
59 10.5 11.0 Emergence of inflorescence completed
Anthesis
60 10.51 11.4 Beginning on anthesis
65 11.5 Anthesis half-way
69 11.6 Anthesis completed
Milk development
70 -
71 10.54 12.1 Kernel watery ripe
73 13.0 Early milk
75 11.1 Medium milk
77 Late milk
Dough development
80 -
83 14.0 Early dough
85 11.2 Soft dough
87 15.0 Hard dough
Ripening
90 -
91 11.3 Kernel hard (difficult to divide with thumbnail)
92 11.4 16.0 Kernel hard (no longer dented with thumbnail)
93 Kernel loosening in daytime
94 Overripe, straw dead and collapsing
95 Seed dormant
96 Viable seed giving 50% germination
97 Seed not dormant
98 Secondary dormancy induced
99 Secondary dormancy lost

References[edit]

  1. ^ Wise K, Johnson B, Mansfield C, Krupke C. "Managing Wheat by Growth Stage" (PDF). Purdue University Extension. Retrieved 29 February 2012. 
  2. ^ Miller, Travis. "Growth Stages of Wheat: Identification and Understanding Improve Crop Management" (PDF). Texas Agricultural Extension Service. Retrieved 29 February 2012. 
  3. ^ Herbek J, Lee C (July 2009). "Section 2. Growth and Development". A Comprehensive Guide to Wheat Management in Kentucky. University of Kentucky College of Agriculture. 
  4. ^ a b Large, E. C. (1 December 1954). "GROWTH STAGES IN CEREALS ILLUSTRATION OF THE FEEKES SCALE". Plant Pathology. 3 (4): 128–129. doi:10.1111/j.1365-3059.1954.tb00716.x. 
  • Lancashire, P.D.; H. Bleiholder; P. Langeluddecke; R. Stauss; T. van den Boom; E. Weber; A. Witzen-Berger (1991). "A uniform decimal code for growth stages of crops and weeds". Ann. Appl. Biol. 119 (3): 561–601. doi:10.1111/j.1744-7348.1991.tb04895.x. 
  • Lancashire, P.D.; H. Bleiholder; P. Langeluddecke; R. Stauss; T. van den Boom; E. Weber; A. Witzen-Berger (1991). "A uniform decimal code for growth stages of crops and weeds". Ann. Appl. Biol. 119 (3): 561–601. doi:10.1111/j.1744-7348.1991.tb04895.x. 
  • Witzenberger, A.; H. Hack; T. van den Boom (1989). "Erläuterungen zum BBCH-Dezimal-Code für die Entwicklungsstadien des Getreides - mit Abbildungen". Gesunde Pflanzen. 41: 384–388. 

External links[edit]

Further reading[edit]

  • J.C. Zadoks, T.T. Chang, C.F. Konzak, "A Decimal Code for the Growth Stages of Cereals", Weed Research 1974 14:415-421.