Jim Graham, Megan Dewdney

UF/CREC

Henry Yonce KAC Agricultural, Inc.

COMPARISON OF COPPER FORMULATIONS FOR

CONTROL OF CANKER ON HAMLIN ORANGES*

* Research supported by CRDF and product manufacturers

Special thanks to Crews Groves

High levels of canker losses occur depending on cultivar,

leafminer, timing of wind-blown rain events w/ fruit size

Site conditions that promote canker are

wide areas without natural windbreaks

Frequent and vigorous flushes on young trees with

leafminer combined with wind exposure promotes

canker even on resistant Valencia

*Occurs when the fruit reaches 0.25-0.5 inches in diameter until fruit is about 1.5 inches in diameter

*Rains in April-May promote early season infection

*The rind is susceptible throughout the entire period of fruit growth, but becomes more resistant with time

Period of greatest fruit susceptibility

Why 21 day interval sprays? (coverage decreases as fruit grows)

Effect time after application on residual copper per surface area

g Copper/fruit Surface Area

Days

0 7 14 21 28

g C

u/fru

it s

urf

ace

are

a

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

a

b bc

d

Hamlin is the one of most susceptible sweet orange cultivars

and comprises 50% of FL orange crop

Previously, copper fungicide was applied to Hamlin 1-2 times

per season to control greasy spot

To control canker, additional copper sprays at 21 day interval

are required for optimal cost/benefit (Behlau et al. 2009)

In young groves number of copper sprays will increase

How many additional sprays are necessary?

What rates and copper formulations are effective?

Challenges posed by Hamlins for canker

control

2011 trial parameters

*4 yr-old Hamlin grove in Hardee Co. with high disease incidence in 2010

*RBD with 5 blocks of 5 trees

*Airblast spray application at 80 gal/acre at 21 day interval

*Fruit disease evaluation: incidence of fruit with canker lesions

*Lesions are classified as “old” if >1/4 in. dia. or “young” if <1/4

*Collected fruit from under middle 3 trees to count fruit drop due to canker (4 X)

Formulations and rates of products tested

(~0.5-1.0 lb metallic Cu/acre) Treatment Manufacturer

/supplier

Metallic Cu

(%)

Rate

(lb/acre)

Metallic

Cu lb/acre

1) Kocide 2000 Dupont 35 4.0 1.4

2) Kocide 3000 Dupont 30 3.0 0.9

3) Kocide 3000 Dupont 30 2.5 0.75

4) Kocide 3000/Magna-Bon Dupont/Magna-

Bon

30/5 1.0/20oz/ac 0.38

5) NuCop 50WP Albaugh 50 2.0 1.0

6) Nordox Allied Botanicals 75 1.33 1.0

7) Cuprofix Ultra 40 UPI 40 3.0 1.2

8) Kentan DF Isagro 40 2.62 1.04

9) Badge X2 Isagro 28 2.68 0.75

10) Cop-R-Quik Nat.Ag. Sol. 12 8.0 oz/ac 0.09

11) Cop-R-Quikz Nat.Ag. Sol. 12 12.0 oz/ac 0.12

12) Americop 40 DF IQV 40 2.5 1.00

13) Magna-Bon x Magna-Bon 5 50 oz/ac 0.19

14) Magna-Bony Magna-Bon 5 40 oz/ac 0.15

15) Untreated check 1(UTC) -- -- -- --

16) Untreated check 2(UTC) -- -- -- --

x 250 ppm, 200 ppm, 150 ppm and 100 ppm for rest of applications y 200 ppm for all apps z 6.0 oz, 5.0 oz, 4.0 oz per 80 gallons

Late April and early May rainfalls produced high

infection of fruit > 0.5 inches in diameter

Sebring RainfallApril-May 2011

Date

Apr 1

Apr 15

May 1

May 1

5

May 3

1

Rain

fall

(inch

es)

0.0

0.2

0.4

0.6

0.8

1.0

Total rainfall

15 min max

Copper spray timing

Tree with highest exposure to wind

have most fruit drop in early June

Kocide 2

000 4.0

lbs

Kocide 3

000 3.0

lbs

Kocide 3

000 2.5

lbs

Kocide 3

000 1.0

lb/M

agna-Bon 2

0 oz

NuCop 50 W

P 2.0

lbs

Nordox

1.33 lb

s

Cuprofix

Ultr

a 40 3

.0 lb

s

Kentan D

F 3.0

lbs

Americ

op 40 D

F 2.5

0 lbs

Badge X2 2

.62 lb

s

Cop-R-Q

uick 8

.0 o

z

Cop-R-Q

uick12.0

oz

Magna-B

on 50 o

z

Magna-B

on 40 o

z

UTC 1

UTC 2

Fru

it c

an

ke

r in

cid

en

ce

(%

)

0

20

40

60

80

100a

ab

ee ee cdecde e cde

abcbcde

abcdabcd

de

abcd

Kocide 2

000 4.0

lbs

Kocide 3

000 3.0

lbs

Kocide 3

000 2.5

lbs

Kocide 3

0001.0 lb

/Magna-B

on 20 o

z

NuCop 50 W

P 2.0

lbs

Nordox

1.33 lb

s

Cuprofix

Ultr

a 40 3

.0 lb

s

Kentan D

F 3.0

lbs

Americ

op 40 D

F 2.5

lbs

Badge X2 2

.68 lb

s

Cop-R-Q

uick 8

.0 o

z

Cop-R-Q

uick 1

2.0 o

z

Magna-B

on 50 o

z

Magna-B

on 40 o

z

UTC 1

UTC 2

Canker

fruit d

rop incid

ence (

%)

0

20

40

60

80

a

ababc

abcd

bcde

bcdebcde

bcde

bcde

cde cdecde dee e

de

Kocide 2

000 4.0

lbs

Kocide 3

000 3.0

lbs

Kocide 3

000 2.5

lbs

Kocide 3

000 1.0

lb/M

agna-Bon 2

0 oz

NuCop 50 W

P 2.0

lbs

Nordox

1.33 lb

s

Cuprofix

Ultr

a 40 3

.0 lb

s

Kentan D

F3.0 lb

s

Americ

op 40 D

F 2.5

lbs

Badge X2 2

.68 lb

s

Cop-R-Q

uick 8

.0 o

z

Cop-R-Q

uick 1

2.0 o

z

Magna-B

on 50 o

z

Magna-B

on 40 o

z

UTC 1

UTC 2

Fru

it d

ropped w

ith c

anker

0

500

1000

1500

2000

2500

6/28/11

8/9/11

9/28/11

11/16/11

GOOD NEWS: In a 3 yr Hamlin trial of 6-8 yr old trees

in the same location with hedgerows

Very low fruit infection and fruit drop

Copper reduced crop loss about 50% and returned on

cost of 4 Cu sprays in 2008 & 09, but not in 2010

Year

2008 2009 2010

Bo

xe

s/tre

e

0.0

0.2

0.4

0.6

0.8

1.0

1.2

without copper

with copper $365/ac

$50/ac $5/ac

*Hamlin fruit drop is highly related to early season fruit infection

* Copper sprays reduce early season infection and fruit drop and provide economic return for the cost of the additional sprays

*No more than 4 sprays are necessary to prevent crop loss as later season infections do not cause fruit drop

* Copper formulations at rates of 0.5-1.0 lb metallic copper are effective, Magna Bon at less metallic may require mixing with Kocide copper to gain comparable control (reduces Cu metal/acre)

* As trees develop hedgerows they become more resistant to canker due to reduced windblown rain penetration of the grove

* Fewer copper sprays are needed after trees canopy closure- “Internal windbreak”

* Proper spacing of trees is important to promote canopy closure as rapidly as possible

Susceptible cultivars at proper spacing on Swingle with

low canker incidence after 3 Cu sprays –

groves located in Arcadia area

8 yr-old Westin on Swingle

7 yr-old Vernia on Swingle

Soil drenches of neo-nicotinoid

insecticides (Admire, Platinum) or

Actigard for control of canker by

Systemic Acquired Resistance (SAR)

Leafminer control essential on the leaf flushes of

young trees and all grapefruit trees

Leafminer results in explosive build-up of canker on mid-

summer leaf flushes

Lapse of leafminer and canker control in July and

resumption of control after next Admire

Canker-LM on July flush

Why control canker on young trees? Prevents cycles

of canker-induced defoliation and tree debilitation

Evaluation of 60 day rotations of SAR inducers Actigard (ASM)

Platinum and Admire for canker management on young trees

Vernia orange

UTC

ASM d

rench

ASM m

icrosp

rinkle

r

THIA-A

SM-IM

ID

ASM/C

H CH

Folia

r can

ke

r (%

)

0

10

20

30

40

50

60

70

a

b

c cc

c

Tree size J

a

n

Feb M

a

r

A

pr

May J

u

n

J

u

l

A

u

g

Sep O

C

t

Nov D

e

c

Reset

(<3’)

Every 8 wks

P A B B A P

Reset

(<3’)

Every 6 wks*

P A A B B A A P

1-2 yr

(3-5’)

Every 8 wks

P A B B A P

1-2 yr

(3-5’)

Every 6 wks

P A B B B B A P

3-5 yr

(5-9’)

bearing

P A

A= Admire (imidacloprid); B=Belay (clothianidin); P=Platinum (thiamethoxam); Products are positioned for use

at certain times of the year based on water solubility and likelihood for significant rain events.

* Two additional Belay applications were still possible for the 6 week schedule listed for resets less than 3 feet

in height.

Actigard and neonicotinoids systemic control of canker

inoculum on leaves insures that no control measures are

needed for canker(copper sprays)on 1-3yr old orange trees

Henry Yonce and Carol Brooks Tony McIntosh

Special Thanks to C. E. Crews Groves!