Optimizing Crop Yield (Shokes, 2008)

• Absolute yield (genetics)

• Attainable yield (environmental and soil conditions)

• Affordable yield (crop value and cost of production)

• Actual yield (minimize stress and timely management)

Variety Selection

• Yield

• Quality

• Market appeal (demand)

• Disease reaction

How do we: Improve crop and soil productivity and increase the efficiency of production in order to enhance quality of life, while exerting minimal negative impact on natural resources and the environment

The power of host-plant resistance, and the power of crop rotation

Peanut Breeding – Dr. Tom Isleib

• Continue to monitor all advanced breeding

lines for their reactions to all four diseases

• Breed for resistance

• Make crosses among lines with different

resistances

• Select simultaneously for resistance to all four

diseases in segregating generations

• Use a winter nursery to achieve two generations

per year and hasten the approach to genetic

stability

Center of Origin

Cultivated peanut

Peanut germplasm

Symptoms in the field include yellowing, wilting and death. Diseased

plants tend to occur in runs within a row.

Cylindrocladium black rot (CBR)

August *1 to harvest

*may cause seedling disease

© 2008 Barbara Shew

Cylindrocladium black rot (CBR)

The rotted roots are black to dark brown and brittle.

Brick red fungal structures (perithecia, arrow) on stems or

pods indicate that CBR is present. Seeds may be speckled.

August 1 to harvest

© 2008 Barbara Shew © 2008 Barbara Shew

© 2008 Barbara Shew

© 2008 Barbara Shew

NC 8C – first CBR resistant cultivar Archive photo provided by Dr. Barbara Shew

CBR resistance screening circa 1980

Archive photo provided by Dr. Barbara Shew

This line may have been NC

Ac 18016 or NC 3033 – both

highly resistant to yield

Resistance in 2004 Photo provided by Dr. Barbara Shew

Perry VA 98R

CBR resistance in Bailey in 2009

Photo provided by Dr. Barbara Shew

Bailey Perry

CBR control: Host-Plant Resistance Photo provided by Dr. Barbara Shew

Use a resistant cultivar in any field with a history of disease and in

any field with a recent history of soybean production

Resistant cultivar Susceptible cultivar

Early Generation Selection Augmented by a Winter Nursery:

A Schematic Diagram of the Program (from Dr. Tom Isleib)

Increase seed at PRWN

Make crosses

Test families for disease resistance

Identify best families

Select for pod traits in best

families

Test for disease, yield, and quality

Feed into mainstream

variety testing program, continue

disease testing

Cycle until genetically

stable

PI

57

66

36

0

.22

55

VA

93

B 0

.73

41

NC

10

C

0.7

19

0

Per

ry

0.7

13

9

NC

9

0.7

08

1

NC

12

C

0.6

84

5

NC

7

0.6

78

6

VA

-C 9

2R

0

.56

17

N

C-V

11

0.5

51

6

Wil

son 0

.55

02

V

A 9

8R

0

.54

98

Geo

rgia

Gre

en

0.5

28

3

Gre

go

ry

0.4

74

5

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

TSW

V In

cid

ence

High pressure Low pressure

Adjusted Mean TSWV Incidence Under Low (1997-1999) and High (2000-2002) Disease Pressure Source: Dr. Tom Isleib

Bailey

Brantley

CHAMPS

Florigiant

Gregory

NC 10C

NC 12C

NC 6

NC 7 NC 9

NC-V 11

Perry

Phillips

VA-C 92R

y = 40.03x - 76461R² = 0.292

y = 0.8806x2 - 3480.2x + 3E+06R² = 0.6008

2500

3000

3500

4000

4500

5000

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Po

d y

ield

(lb

/A)

Year testing initiated

Experimental lines Cultivars

Progress in Yield, 1970-2009 (Provided by Dr. Tom Isleib, NC State University)

Accelerating and Enhancing

Peanut Cultivar Development

Through a

Nationwide Marker-Assisted

Breeding Network

Early Generation Selection Augmented by a Winter Nursery:

A Schematic Diagram of the Program

Increase seed

at PRWN Make crosses

Test families for

disease resistance

Identify best

families

Select for pod

traits in best

families

Test for disease,

yield, and

quality

Feed into

mainstream

variety testing

program,

continue disease

testing

Cycle until

genetically

stable

Early Generation Selection Augmented by a Winter Nursery:

Locations Used for Different Phases of the Program

Crosses: NCSU greenhouses (Raleigh)

Winter increases: Illinois Crop Improvement farm at Juana Diaz, PR

Disease tests: TSWV at PBRS (Lewiston), 20” spacing, no insecticide

Leaf spot at PBRS, no fungicide

CBR at Chowan Co. (on-farm), no metam sodium

Sclerotinia at Gates Co. (on-farm), no fluazinam

Yield trials: PBRS, UCPRS (Rocky Mount), BBTRS (Whiteville)

Raleigh

SB site

CBR site

PBRS UCPRS

BBTRS

Table 13. Characteristics of commercially grown Virginia market type peanut Varieties.

Factors

Bai

ley

CH

AM

PS

Gre

go

ry

NC

-V 1

1

Per

ry

Ph

illi

ps

Su

gg

Growth habit

(R=runner; SR=semi-runner)

SR

R

R

R

SR

SR

SR

Heat unit requirement

(Approximately 15 HU per day

in September

2,480

2,450

2,525

2,510

2,585

2,510

2,495

Comparative days to optimum

maturity

-3

-5

+1

0

+5

0

-1

Seed coat color

Tan

Pink

Pink

Pink

Pink

Pink

Pink

Seed per pound

600

535

450

625

525

545

545

Need for calcium

(M=moderate; H=high)

M

M

H

M

M

M

M

Table 14. Peanut (lbs./acre) as influenced by variety, planting date, and

digging date at Lewiston-Woodville during 2009, 2010, and 2011.

Planting date Digging date CHAMPS Perry

May 5 September 8 3284 3257

May 25 September 8 2958 2798

June 8 September 8 1889 1762

May 5 September 20 4087 4313

May 25 September 20 3691 3725

June 8 September 20 2814 2682

May 5 October 7 4332 4238

May 25 October 7 4514 4506

June 8 October 7 3921 3570

May 5 October 20 3351 4086

May 25 October 20 3931 4564

June 8 October 20 3693 3604

Irrigating Peanut

Growth stage Plant indicator Drought susceptibility

Germination (1-2 weeks) Planting to emergence High

Vegetative growth (5-6 weeks) Emergence to flowering/pegging

Low

Pod development (8-9 weeks) Flowering/pegging to pod formation

High

Maturation (5-6 weeks) Pod formation to harvest Moderate

Table 1. Crop response to sub-surface drip irrigation

Yield increase over non-

irrigated (%)

Crop Years Trials Average Range

Peanut 2001-04, 2010-11 6 21 6 to 34

Cotton 2001-09, 2011 9 30 1 to 54

Corn 2008-11 4 47 34 to 59

Ratio 1.25 to 1.43 (SSD plus rain/rain) (ave. 1.30) when response was not

observed and 1.42 to 4.67 (ave. 2.04) when response was observed

(response in 14 of 19 crop/year combinations from 2001-2011). Rainfall of

18.9 to 24.9 inches (ave. 20.6) when response was not observed and 3.6 to

19.9 inches (ave. 12.2) when response was observed.

Peanut Response to Rainfall (inches of rain.) Data are from Suffolk, Virginia (Dr. Pat Phipps)

June July Aug Sep Total Yield (lb/A)

Bad season

1985 5.20 2.95 3.03 2.96 14.14 2325

1997 0.69 10.74 1.25 1.99 14.66 2550

2002 1.66 5.53 2.22 2.96 12.37 2100

2007 3.00 1.71 5.00 0.43 10.17 2500

Good season

2004 5.10 12.53 11.00 5.15 33.78 3250

2006 10.08 3.66 2.50 9.16 25.04 3200

2008 1.56 5.58 2.18 6.01 15.33 3350

2009 3.40 4.86 3.38 7.69 19.33 3500

2010 1.35 1.60 - - - -

Rainfall threshold

Normal 4.21 5.79 5.71 4.49 20.20 -

75% normal 3.16 4.34 4.28 3.36 15.15 -