Session ThreePest Disease Control Strategies, Integrated

Production Systems and the Impact on Market Access

Session ThreeSession ThreePest Disease Control Pest Disease Control Strategies, Integrated Strategies, Integrated

Production Systems and the Production Systems and the Impact on Market AccessImpact on Market Access

New Zealand and Australia Avocado Grower’s Conference’05 20-22 September 2005 Tauranga, New Zealand

New Zealand and Australia Avocado New Zealand and Australia Avocado GrowerGrower’’s Conferences Conference’’05 05 2020--22 September 2005 22 September 2005 TaurangaTauranga, New Zealand, New Zealand

Managing avocado pestsManaging avocado pests withwithromance, intrigueromance, intrigue and war and war ––

integrating pheromones, assassinsintegrating pheromones, assassins and and weapons of mass destructionweapons of mass destruction

Geoff WaitePrincipal Entomologist

Queensland Department of Primary Industries and FisheriesMaroochy Research Station

Nambour Queensland, Australia

Managing avocado pests withromance, intrigue and war –

integrating pheromones, assassins and weapons of mass destruction

Geoff WaitePrincipal Entomologist

Queensland Department of Primary Industries and FisheriesMaroochy Research Station

Nambour Queensland, Australia

In many districts, the Queensland avocado pest complex is dominated by fruitspotting bugs

Amblypelta nitida AmblypeltaAmblypelta lutescenslutescensThis presentation will focus

on these bugs as they arethe key pests in the system

Fruitspotting bug damageFruitspotting bug damage

The The RomanceRomanceFinding a mate

For an insect, what does finding a mate involve?

Being where the action is, helps!Host plants facilitate this by attracting insects to a common feeding site.

Either sex may produce the attractant pheromone, depending on the insect group

In moths, the female produces the pheromone

Males produce the pheromone in some weevils and true bugs

Fruitspotting bug males produce the pheromone

Note the interest in the mating pair from all these females

For insects, once they get to the venue, attraction to the opposite sex on the ‘dance floor’ is usually via pheromones.

Sex - a fatal flaw to be exploited in a species’ behaviour!

Aeration technique used for collecting fruitspotting bug pheromones

SPME sampler – allows direct desorption & analysis in Gas Chromatograph of pheromones & host volatiles

Volatile compounds (pheromones) adsorbed onto active film coating the fibre

Volatile compounds absorbed by activated charcoal or Poropak Q

Solid Phase Micro-extraction - SPMEAeration

Fruitspotting bugs have glands that produce defensive odours, but they have no discrete pheromone-producing glands.

For these bugs, the pheromones have to be collected from the airafter they are released to enable identification of the active compounds.

Compounds of particular Compounds of particular interest for each speciesinterest for each species

EE--ocimeneocimene epoxideepoxide((myroxidemyroxide))

EE--nerolidolnerolidol

Live bugs Amputating the antenna Antenna attached to electrodes

Simultaneous injection of aeration sample into EAG device and GC

Readout of antennal reaction (AEG) top graph,and active compounds (GC) lower graph

Antennal reaction to ocimene epoxide, nonanal and decanal

Sorting out the active compounds - USDA laboratory, Beltsville

ocimene-epoxidenonanal

decanal

Insect semiochemistryThe pheromone may work in combination with host volatiles – after all, wining and dining are a part of human romancing, so why not with bugs?

cineolecineole

nonanalnonanal

nonanalnonanal

cineolecineole

EE--ββ--ocimeneocimene

decanaldecanal

LonganLongan

Custard appleCustard apple

decanaldecanal

napthalenenapthalene

SPME samples of green fruit

These small flies have presumably been attracted by volatile chemicals –are these produced by the ‘stressed’ bee or the assassin bug?

Pheromones and host volatiles could be used:

In traps for monitoring populations

In an attract and kill strategy in combination with decoy trees

Female Amblypelta nitida on trap containing ocimene-epoxide, nonal and decanal

The IntrigueThe enemy within

In IPM systems, conservation biological control is criticalAssassins in action

RedbandedRedbanded thripsthrips infestation terminated by natural enemies infestation terminated by natural enemies -- on avocado in street in on avocado in street in BuderimBuderim

The WarThe War

Pesticides, weapons of mass destruction Pesticides, weapons of mass destruction of both of both beneficialsbeneficials and pests, are and pests, are indispensibleindispensible in most commercial orchards.in most commercial orchards.

Chemical warfare waged sensibly,Chemical warfare waged sensibly,generally produces quality fruit. generally produces quality fruit.

However ------

Inappropriate use of some types of chemical can cause problems, especially with scales

and mites

So, how should we respond to pest invasions?

The elements of ‘romance’ and ‘intrigue’ that are effective against individual pests should be applied (pheromones if available, conservation biological control)

Incorporate these in a practical and sustainable strategy that usestactical and targeted chemical warfare against pests for which other management options are not available

Sustainable IPM system

In addition to understanding pest biology, behavioural and ecological studies are criticalto determine opportunities for developing newmanagement strategies, especially for key pests.

Fruitspotting bugs have also exhibited preferences for certain avocado (and macadamia) cultivars, which could be used as trap trees in a ‘Hass’ orchard

For fruitspotting bugs, this has led to the formulation of the ‘hotspot’ strategy

0

50

100

150

200

250

300

350

9 Sep

t.3-O

ct14

-Oct

21-O

ct4-N

ov17

-Nov

28-N

ov17

-Dec

8-Jan

5-Feb

2-Apr-

04

No.

dam

aged

frui

t

Pinkerton 1Pinkerton 2Fuerte 1Fuerte 2Fuerte 3Hass 1Hass 2Hass 3Hass 4

Fruitspotting bug damage on individual unsprayed trees of Fruitspotting bug damage on individual unsprayed trees of various avocado cultivars, Maroochy 2003various avocado cultivars, Maroochy 2003--0404

Typical fruitspotting bug hotspot situationTypical fruitspotting bug hotspot situation

Columns (distance in meters)

-100 -80 -60 -40 -20

Row

s(d

ista

nce

in m

eter

s)

10

20

30

40

50

60

70

IPMapplied

849

849

849

849246

246

246

246741

741

741

741A 4

A 4

A 4

A 4

Fruitspotting bugdamage

0 %10 %20 %30 % 40 %50 %60 %

Standardchemical

Egg parasiteonly

Nutborerpheromone

Fruitspotting bug damage on macadamias 2003-04

Bug sourceBug source

Bug sourceBug source

Maddox & Huwer, 2004

Fruitspotting bug edge effect in passionfruit

Outside row: Undamaged fruit = 62Damaged fruit = 117

65.4%

Second row:Undamaged fruit = 169Damaged fruit = 6

3.4%

identifying and using hotspots to monitor fruitspotting bug infestations

spraying only the hotspots, but more frequently to prevent bug dispersal through the orchard

using more susceptible cultivars as decoy/trap treese.g. Fuerte

Romance, intrigue and tactical warfare can becombined in a total orchard management system (IPM)

for any avocado pest complex.

In Queensland, the system will be enhanced by:In Queensland, the system will be enhanced by:

Particle film (SurroundParticle film (Surround®)®) has beenhas been applied as an insect deterrent applied as an insect deterrent and sunscreen and sunscreen –– but it washes off in rain & may induce scale outbreaksbut it washes off in rain & may induce scale outbreaks

Exclusion nets are not an option in avocados