Turfgrass Entomology UpdateTurfgrass Entomology Update

Rutgers UniversityRutgers University

Albrecht KoppenhöferAlbrecht Koppenhöfer

• Mating disruption of oriental beetleMating disruption of oriental beetle

• Biological and biorational control of Biological and biorational control of annual bluegrass weevilannual bluegrass weevil

• Steinernema scarabaeiSteinernema scarabaei for long term for long term white grub suppressionwhite grub suppression

• Entomopathogenic nematode Entomopathogenic nematode application and ecologyapplication and ecology

• New chemistry for white grubs and New chemistry for white grubs and annual bluegrass weevil managementannual bluegrass weevil management

Research Projects:Research Projects:

• isolated from epizootics in Japanese and isolated from epizootics in Japanese and oriental beetle larvae in turfgrass areas in oriental beetle larvae in turfgrass areas in central NJcentral NJ

• biology similar to that of other EPN speciesbiology similar to that of other EPN species

• appears to be rather specific to white grubsappears to be rather specific to white grubs

Steinernema scarabaei for long termwhite grub suppression

Nematode-infected grubsNematode-infected grubs

S. scarabaeiS. scarabaei H. bacteriophoraH. bacteriophora

• High pathogenicity High pathogenicity and high field efficacy and high field efficacy against many white against many white grub speciesgrub species

Long-term suppressionof white grubs by S. scarabaei

- Field experiments -

• 4’ x 4’ Kentucky bluegrass plots enclosed 4’ x 4’ Kentucky bluegrass plots enclosed by 5” high ‘Emerald Edge’.by 5” high ‘Emerald Edge’.

• 160 OB larvae (late L2 & early L3; 10/ft2) 160 OB larvae (late L2 & early L3; 10/ft2) released 1 wk before treatment.released 1 wk before treatment.

• Application with watering can (~0.5” water) Application with watering can (~0.5” water) in mid-September (early L3).in mid-September (early L3).

• Field irrigated as necessary to keep out of Field irrigated as necessary to keep out of excessive drought stress.excessive drought stress.

AnnualAnnualWhite White GrubGrub

SeasonalSeasonallife-life-

cyclecycle

Timing of sampling activitiesTiming of sampling activities

EPNEPN EPNEPNEPNEPNGrubGrub

EPNEPNGrubGrub

Appl.Appl.EPNEPN

Long term Long term suppressionsuppression

of whiteof whitegrubs by grubs by

S. scarabaeiS. scarabaei

Expt. 1Expt. 1Treated 9/17/02Treated 9/17/02

0-2.5 B 0-2.5 B SsSs/ha/ha

Sep-02

Oct-02

Apr-03

Aug-03

Oct-03

Apr-04

May-04

Aug-04

Oct-04

Apr-05

May-05

Aug-05

Oct-05

No

. o

f S

. sc

arab

aei

/ 20

0 g

so

il

0

50

100

150

200

0.00.41.02.5

A.

ori

enta

lis

larv

ae /

0.1

m2

0

2

4

6

8

10a

b

a

b b

a

b

b b

b

a

bbc

a

a

a

ba

a

a

b

a

bb

ab

b b

a

a

a

b

S. scarabaei rate(x 109/ha)

a

b

b

ab

Long-term Long-term suppressionsuppression

of whiteof whitegrubs by grubs by

S. scarabaeiS. scarabaei

Expt. 2Expt. 2Treated 9/19/03Treated 9/19/030-0.6 B 0-0.6 B SsSs/ha/ha

A.

ori

enta

lis

larv

ae /

0.1

m2

0

2

4

6

8

10

Sep-03

Oct-03

Apr-04

May-04

Aug-04

Oct-04

Apr-04

May-05

Aug-05

Oct-05

No

. o

f S

. sc

arab

aei

/ 20

0 g

so

il

0

50

100

150

200

0.00.060.120.240.6

S. scarabaeirate (x 109/ha)

a

a

bb

ab

a

b

bb

b

a

ab

b b

b

a

ab

b

ab

abb

a

aa

a

a

bbb

b

Long-term suppressionLong-term suppressionof of A. orientalisA. orientalis in turfgrass in turfgrass

by by S. scarabaeiS. scarabaei

Field experiments (1.5 m2 microplots, 10 L3/0.1 m2)

Months after Months after S.S. scarabaei-scarabaei-ApplicationApplication

SsSs rate rate (x 10(x 1099/ha)/ha)

1 1 (Oct)(Oct)

8 8 (May)(May)

13 13 (Oct)(Oct)

20 20 (May)(May)

25 25 (Oct)(Oct)

32 32 (May)(May)

37 37 (Oct)(Oct)

0.4 – 2.50.4 – 2.5 86–100 96–100 62–92 69–94 0–94 63–83 0–64

0.1 – 0.250.1 – 0.25 50–77 86–100 76–77 93–95 33–50 --- ---

0.060.06 9 89 41 100 8 --- ---

ConclusionsConclusions:S. scarabaeiS. scarabaei for white grub control: for white grub control:

1.1. has outstanding potential as a curative has outstanding potential as a curative control agent for many white grub species.control agent for many white grub species.

2.2. suppresses grub populations for 1-2 years suppresses grub populations for 1-2 years after application.after application.

3.3. is effective in a wide variety of soil types.is effective in a wide variety of soil types.

4.4. may be a good candidate for inoculative may be a good candidate for inoculative releases.releases.