2015 Sorghum Sugarcane Aphid Spray Systems Studies

David BuntinUniversity of Georgia

Sorghum – Sugarcane Aphid Research Exchange Meeting

New Orleans, LAJanuary 7 – 8, 2016

Question #1: What is the efficacy of season long programs that incorporate the industry leader Transform?

Collaborators

Name Affiliation Trial Location

PlantDate

Spray Date

David Buntin University of Georgia Griffin, GA 6/8/15 7/15, 8/7, 8/20

David Kerns & Sebe Brown

Louisiana State University

Macon Ridge Res. Station

6/10/15 7/8, 7/13 7/21-7/18

Ali Zarrabi, Tom Royer & Kris Giles

Oklahoma State University

Lane, OK 6/4/15 8/17/15

Robert Bowling & Mark Wleczyk

Texas A&M Agrilife Extension

Rosenberg, Texas

4/12/15 regrowth

9/06/15

Spray Systems ProtocolSystem Pre-boot/ Boot

stageFlowering Milk/dough

stage1) Untreated None None None

2) LTT Lorsban Transform Transform

3) LST Lorsban Sivanto Transform

4) TST Transform Sivanto Transform

5) STT Sivanto Transform Transform

6) TTT Transform Transform Transform

Harvest if needed: Transform @ 1 oz

Other pests as needed:Midge: pyrethroidWhorl-worms or Headworms: Prevathon

GA MethodsHybrid: SS800ANo insecticide seed treatment.Sprays:• Lorsban Advanced @ 2 pints per acre• Transform 50WG @ 1 oz per acre• Sivanto 200SL @ 4 fl. oz. per acre

Sprayer: CO2-powered backpack sprayed @ 40 psi, 15 gpa

Data:• Aphid counts per leaf• Plant injury rating (Burd et al. 1993)• Heading %• Grain yield adjusted to 14% moisture content

SCA numbers in sorghum spray systems trial, Georgia 2015

0

50

100

150

200

250

300

Unt LTT LST TST STT TTT

Sample Date

SCA

per l

eaf

Unt = Untreated, L = Lorsban @ 2pt, T = Transform @1 oz, S = Sivanto @ 4 fl. oz.

Spray

Spray

Spray

510 330

3d 6d 11d 19d 26d 33d 40d

*

Effect of Sugarcane aphid spray system on aphid-days of sorghum, Georgia 2015

Untreated LTT LST TST STT TTT0

1000

2000

3000

4000

5000

6000

7000

8000

9000 a

b bc

cd dbcd

Spray System (boot/flower/dough stage sprays)

Aphi

d da

ys

Unt = Untreated, L = Lorsban @ 2pt, T = Transform @ 1 oz, S = Sivanto @ 4 fl. oz.Means with same letter not significantly different (LSD (α = 0.05) of LSmeans)

Effect of SCA spray systems on Sorghum plant injury rating and grain head emergence,

Georgia 2015

Un-treat

ed

LTT LST TST STT TTT0

102030405060708090

100

c

bb

a a a

Spray System

% G

rain

hea

d em

erge

nce

Un-treat

ed

LTT LST TST STT TTT0123456789

a

b b

cd

cd

Spray System

Plan

t inj

ury

ratin

g

Means with same letter not significantly different (LSD (α = 0.05) of LSmeans)Unt =Untreated, L = Lorsban @ 2pt, T = Transform @ 1 oz, S = Sivanto @ 4 fl. oz.

Effect of Sugarcane aphid spray system on grain yield of sorghum, Georgia 2015

Untreated LTT LST TST STT TTT0

10

20

30

40

50

60

70

d

cbc

ab

a

ab

Spray System (boot/flower/dough stage sprays)

Grai

n yi

eld

(Bu/

acre

)

Unt = Untreated, L = Lorsban @ 2pt, T = Transform @ 1 oz, S = Sivanto @ 4 fl. oz.Means with same letter not significantly different (LSD (α=0.05) of LSmeans, Proc GLIMMEX)

LA Methods

§Milk/dough stage spray not done; below threshold¶First spray at July 10, 2015.• All seed with Cruiser seed treatment. • L = Lorsban Advanced @ 2 pints per acre• T = Transform 50WG @ 1 oz per acre• S = Sivanto 200SL @ 4 fl. oz. per acreSprayer: Self-propelled spider sprayer @ 60 psi, 10 gpaData: • Aphid counts per leaf• Grain yield adjusted to 14% moisture content

System Pre-boot/ Boot stage¶ Flowering

1) Untreated None None

2) LT Lorsban Transform @ 13 days

3) LS Lorsban Sivanto @ 13 days

4) TS Transform Sivanto @ 21 days

5) S Sivanto None

6) T (Late) Transform 5 days late None

Systems Test - Week 1Macon Ridge Research Station

Mean num

ber of aphids per leaf

0

200

400

600

800

1000

1200Pre-treatment

D. Kerns & S. Brown,

Not sprayedon time

July 8, 2015 V7 Stage

D. Kerns & S. Brown,

Mean num

ber of aphids per leaf

0

200

400

600

800

10005 DAAP 1

a

a

b

Systems Test - Week 2Macon Ridge Research Station

July 13, 2015 Boot Stage

Mean num

ber of aphids per leaf0

100

200

300

400

500

600

7008,3 DAAP 1,2

a

b

Systems Test - Week 3Macon Ridge Research Station

July 16, 2015 Heading Stage

Sprayed with Transform5 days late

Mean num

ber of aphids per leaf

0

100

200

300

400

500

13,8 DAAP 1,2 a

b b

cc c

Systems Test - Week 4Macon Ridge Research Station

D. Kerns & S. Brown,

July 21, 2015 50% bloom

2nd Spray @ 13 days with

Transform

2nd Spray @ 13 days with Sivanto

Mean num

ber of aphids per leaf

0

20

40

60

80

100

120

14020,15,7 DAAP 1,2,3 a

bb b

b

a

Systems Test - Week 5Macon Ridge Research Station

D. Kerns & S. Brown,

July 28, 2015 75% bloom

2nd Spray @ 20 days with

Sivanto

D. Kerns & S. Brown

Mean num

ber of aphids per leaf

0

5

10

15

20

25

30

35

27,22,14 DAAP 1,2,3

a

a

aa

a

a

Systems Test - Week 6Macon Ridge Research StationAug. 6, 2015

3rd Spray treatments not needed, all plots below threshold

Yield (bu/acre)

0

10

20

30

40

50

60

aa

a

a

b

b

Systems TestMacon Ridge Research Station

D. Kerns & S. Brown

Grain Yield @ 14% moisture Aug. 31, 2015

ProgramNo. Product Rate

(oz/A) 7-d 14-d 21-d Yield(BU/A)

1 Untreated N/A N/A 84 a 978 a 667 a 27.0 NS

6 Transform 1.0 fl oz/A 2 b 490 b 510 b 32.1 NS

2 Transform 1.0 fl oz/A 2 b 189 c 418 bc

30.1 NS

4 Transform 1.0 fl oz/A 2 b 249 c 395 bc 32.1 NS

3 Transform 1.0 fl oz/A 3 b 247 c 373 c 30.7 NS

5 Transform 1.0 fl oz/A 1 b 207 c 350 c 31.6 NS

LSD (0.05%) 34 231 124 9.9

Season-long systems program for management of SCA in Grain Sorghum - Lane, OK

Ali Zarrabi, Tom Royer & Kris Giles

Hybrid: KS 585First aphid found on July 14th

Sprayed Aug. 17th at milk/soft dough stage. CO2 backpack sprayer @ 22 PSI and 20 gpa.Harvest on Sept. 23rd.

11-19% more yield but NS

Uneven heading and variable panicle maturity

Key Learnings• Timing of first spray difficult when populations are

building quickly.• Lorsban as first spray on preboot/boot stage less

effective than Transform or Sivanto.• Transform effective for about 14 days, second

application needed for season-long control. • Sivanto effective. As pre-flowering spray,

sometimes 1 application provided control through flowering.

• Timing of first spray at preboot/boot stage of Transform or Sivanto critical to avoid yield losses.

Next Steps• Repeat trials• Focus on preboot/boot through flowering

stages. • Maybe add with and without seed

treatment.

DiscussionWell timed Insecticide sprays can control sugarcane aphid and prevent injury and yield loss.

But can we afford it!