1. Chad Lee © 2006 University of Kentucky 1 Wheat Growth and Development Presentation by: Chad Lee, Grain Crops Extension Specialist University of Kentucky

2. Chad Lee © 2006 University of Kentucky 2 Most of the information comes from: ID-125: A Comprehensive Guide to Wheat Management in Kentucky

3. Chad Lee © 2006 University of Kentucky 3 Objectives Review Growth Stages Freeze Sensitivity Key developmental stages

4. Chad Lee © 2006 University of Kentucky 4 Wheat in Kentucky: Soft Red Winter Wheat Flour for cookies, pastries, crackers, etc. 4 th most valuable crop in Kentucky. Approximately 400,000 acres raised for grain.

5. Chad Lee © 2006 University of Kentucky 5 Wheat Growth Stages Growth Period FeekesDescription Tillering1 - 5 One shoot through pseudo-stem. Stem Extension 6 – 10 First node visible through flag leaf sheath fully visible. Heading10.1 – 10.5 First spikelet of head visible through All heads out of sheaths. Flowering10.51 - 10.54 Beginning of flowering through flowering completed. Ripening11.1 – 11.4 Milky ripe seeds to ripe for harvesting.

6. Chad Lee © 2006 University of Kentucky 6 Important Steps in Development Tiller NumberFeekes 6 Head SizeFeekes 3 Kernel NumberFeekes 5-6 Kernel SizeFeekes 8-11.2

7. Chad Lee © 2006 University of Kentucky 7 Feekes Scale StageScale Tillering1-5 Stem Extension6-10 Heading10.1-10.5 Flowering10.51-10.54 Ripening11.1-11.4

8. Chad Lee © 2006 University of Kentucky 8 Feekes Scale StageScaleDescription Tillering1 One shoot, first leaf through coleoptile. 2 Beginning tillering: one shoot, one tiller. 3 Tillers formed, leaves often twisted spirally. Main shoot and six tillers. In some varieties, plant may be creeping.

9. Chad Lee © 2006 University of Kentucky 9 Feekes Scale StageScaleDescription Tillering4 Start of erection of pseudo- stem; leaf sheaths beginning to lengthen. 5 Pseudo-stem (formed by sheaths of leaves) strongly erected.

10. Chad Lee © 2006 University of Kentucky 10 Feekes Scale StageScaleDescription Stem Extension 6 1 st node of main stem visible at base of shoot. 7 2 nd node of main stem; next to last leaf 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.

11. Chad Lee © 2006 University of Kentucky 11 Feekes Scale StageScaleDescription Heading10.1 First spikelet of head just visible. 10.2 ¼ of heading process completed. 10.3 ½ of heading process completed. 10.4 ¾ of heading process completed. 10.5 All heads out of sheath.

12. Chad Lee © 2006 University of Kentucky 12 Feekes Scale StageScaleDescription Flowering10.51 Beginning of flowering. 10.52 Flowering complete to top of head. 10.53 Flowering complete at base of head. 10.54 Flowering complete; kernel watery ripe.

13. Chad Lee © 2006 University of Kentucky 13 Feekes Scale StageScaleDescription Ripening11.1 Milky ripe. 11.2 Mealy rip; contents of kernel soft but dry. 11.3 Kernel hard (difficult to divide with thumbnail) 11.4 Ripe for cutting. Straw dead.

14. Chad Lee © 2006 University of Kentucky 14 Freeze Injury to Wheat

15. Chad Lee © 2006 University of Kentucky 15 Freeze Injury to Wheat Stage Feekes Stage Approx. Injurious Temp., 2 hrs (ºF) Yield Effect Tillering1-512Slight to Moderate Jointing6-724Moderate to Severe Boot1028Moderate to Severe Heading10.1- 10.5 30Severe

16. Chad Lee © 2006 University of Kentucky 16 Freeze Injury to Wheat Stage Feekes Stage Approx. Injurious Temp., 2 hrs (ºF) Yield Effect Flowering10.51- 10.54 30Severe Milk11.128Moderate to Severe Dough11.228Slight to Moderate

17. Chad Lee © 2006 University of Kentucky 17