1. Jenny Clement Koebernick
Yield: Understanding where the gains have come from and what to expect in the future.
Jenny Clement Koebernick

2. What is a cultivar?

3. A Breeder’s job Improve the cultivar by:
Combine traits
Selecting superior plants with these new traits
Stabilizing the genetics
Involves time, each season is a cycle of breeding
Most traits stabilize after cycles

4. Role of Private vs Public breeding programs
Private breeding programs include: Companies such as Delta and Pine Land Company, FiberMax, Phytogen, Americot, etc.
Primary focus is on yield
Public breeding programs include: USDA-ARS, university and experiment stations such as Auburn, UGA, Texas A&M, etc.
Primary focus is on native traits (not much focus on yield but yield components)

5. U.S. Cotton yield,
Source: USDA-NASS, 2012

6. Yield gain due to cultivar, management & their interaction 325 CSIRO experiments over 30 years
+297 lb/ac over 30 years
Liu et al FCR 2013

7. Two step changes in cotton yield gains

8. Prior to Boll Weevil Eradication
Management- Plant early maturing varieties.
Earlier maturing varieties reduced losses by altering the timing the weevil attacked the plant
After eradication- longer maturing varieties were made available and the grower could maximize the season length.
If the plant has more time to put on bolls i.e. increased yields

9. From 2 bale cotton to 4 bale cotton
Use to grow 2 bale cotton- no matter how you grew it.
GM protection from helicoverpa allowed a higher percentage of boll setting and retention in the lower and mid canopy.
One reason- improved leaf health which resulted in high photosynthesis

10. Will it continue to increase?
YES!
It will come from improved crop protection in cultivars.

11. Recorded potential yield
Location
Yield as reported
Yield
(lb lint/ac)
Harvest method
Source
Xinjiang, China, 2013
kg/mu (0.067 ha)
4460*
Hand?
xinjiang‐sets‐world‐record‐ for‐cotton‐production‐ 13259/
Texas, USA, 2014
6.88
bales/ac
3449
mechanical
Horton (2014).
NSW, Australia, 2015
15.97
bales/ha
3234
Arizona, USA, 1982
5.41 bales/ac
3041
Pennington (1983).
*Assumed lint was 40% of seed cotton
Cotton is highly sensitive to stress. This reduces the potential to <1500 lb/ac with some states not even averaging 1000lb/ac

12. Cotton is sensitive to stress
~12.8% loss to seedling diseases each year
16% to pests
Water stress will reduce yield by 17lb/ac each day during early flowering
48% total loss over the growing season
Moderate soil deficiencies of N-50%, P-37%, K- 20% yield loss
With herbicide, can lose 7% to weeds
Cumulative effects: Pests, weeds and disease can account for 30%

13. Two step changes in cotton yield gains
The next step change:
Improving and implementing management guidelines for new cultivars

14. Stacking Traits Target Spot Management Fiber Quality
Yield
Target Spot
Fiber Quality
Drought resistance
Management

15. Five factors keeping us from high yields
Limited water
Limited nutrients
Inadequate crop protection
Inadequate labor/mechanization
Inadequate knowledge

16. How does the Australian industry have such high yields?
Key region (>50%)
Recent expansion (>198,000 ac )
742,000 ac (≈93% irrigated), produce > 5 million bales, 3rd largest exported behind the US

17. How does the Australian industry have such high yields?
AUS industry:
Environment- long cloudless days, increased solar radiation
Breeding program- there is one and it functions as a collaborative unit
CSIRO---CBA---CSD
80:1 investment
Growers are quick to take up technology- i.e complete conversion to round bale pickers
Collaboration
US industry:
Separate units
Private vs Public
Less communication
Heavy weed pressure
Competitiveness is not allowing us to push the boundaries

19. Conclusion: How to achieve this step change?
Collaborative effort across the cotton belt
State programs- Extension needs support in updating guidelines
Private and public entities will need to work more closely together- increased cultivar turnover is not going to make this easy.

20. Questions?
Thank you to Cotton Inc, Alabama Cotton Comission, Alabama Experiment Station and Auburn University