Berry Crop

Alternative ‘Pest-Pective’

Background to Pest Management in Greenhouse Berry production

Berries by nature are an easy pick and ready to eat fruit without the necessity for peeling.

Food safety and the limited number of chemical controls are the underlying motivation for primary producers to adopt Integrated Pest Management (IPM)

Berries are also seasonal due to the chilling requirement or vernalisation to ensure flowering.

Protected cropping structures provide the option to modify the growing environment and manipulate crop production opportunities.

Using a soilless substrate or growing media safeguards consistency in moisture retention, air porosity, nutrient management and regulation of drainage.

However inadvertently, these adjustments of the environment and the root-zone can lead to conditions conducive for pest and disease proliferation!

Integrated Pest Management Strategies for Greenhouse Berries

Nuffield Study Objectives

My primary objective was to look for emerging and innovative technologies in IPM globally.

With the Nuffield golden key I could explore and assess best practice IPM strategies for greenhouse hydroponic berry crops.

I wanted to identify new technologies associated with bio-control agents (BCA’s) for commercial application whilst maintaining the overall quality of soft fruit.

I needed to learn about entomovectoring when a pollinating insect is used as a vector to spread a substance used in bio-control for plant diseases.

Above all I was looking for practical and commercially viable recommendations for growers adopting IPM in intensive greenhouse hydroponic production of berries within Australia.

Study Method

My plan of attack to complete this study was to meet with researchers and scientists to get background on what is known and new in this field.

I also met with suppliers of bio-controls and beneficial insects and the breeders of the berry crops to see what they are doing through their breeding programs to assist with pest and disease management.

Plus, I made sure that I covered a cross-section of large and small scale growers with entry level as well as sophisticated protective structures. Growers willingly showed me what is currently and successfully being used and implemented on a regular basis on their farms.

IPM for greenhouse hydroponic berry growers equates to a common sense, proactive approach to crop protection.

IPM includes the following factors with the respective weighting;[/cs_text][x_columnize]

1) Action Thresholds

These need to be established by the grower in order to set parameters and boundaries for when to take action.

2) Physical Controls

These are geared towards creating the optimum growing environment and protection from various climate and pest and disease elements.

The limitations and variations of physical control correlates with the level of investment and the cost / benefit outcome, including;

• Greenhouse structures
• Covers
• Ventilation
• Screens
• Heating
• Cooling
• Floor covers
• Raised growing benches

3) Natural Controls

Advancements in the benefits of non-commercial crops provides a range of options in managing and implementing biological pest control.

a) Banker plants provide a host for non-pest insects and also for the establishment of beneficial insects.

b) Indicator and trap plants provide for early detection.

c) Companion plants attract pollinators and provide alternative food sources.

d) Nature strips attract and repel in a push / pull scenario.

4) Cultural Controls

The focus of cultural controls is to prevent or suppress an incursion by altering the environment and / or the condition of the host and / or the behaviour of the pest and disease.

This disruption of the normal relationship between pest and host makes pests less likely to survive, grow or reproduce.

• Propagation material
• Plant nutrition
• Water management
• Growing media
• Crop maintenance
• Genetics and resistance
• Hygiene
• Sanitation
• Biosecurity
• Sterilisation
• Site selection
• Greenhouse orientation

5) Biological Controls

include mites, bugs, lacewings, beetles and thrips supplied in Controlled Release Sachets (CRS) or loose carrier material.

Types of Biological Control Agents (BCA’s) that target only insect pests include;

• Predators
• Parasitoids
• Parasitic nematodes

The main issues for greenhouse berry crops;

• Two-spotted mites
• Thrips
• Aphids
• White Fly

All of these pests are everywhere at once and their efficient reproductive capacity gives them the ability to form increased resistance to chemicals.

They are piercing and sucking pests which is taxing to the plant but aphids, thrips and white fly have the potential to vector and transmit diseases such as TSWV

Thrips Predators

1) Neoseiulus cucumeris
2) Amblyseius swirskii – not present in Australia
3) Transeius montdorensis (AU)
4) Amblydromalus limonicus – not present in Australia
5) Orius laevigatus – not present in Australia
6) Orius armatus (AU)

Aphid Predators

1) Aphidius colemani, Aphidius matricariae, Aphidius ervi
2) Aphelinus abdominalis
3) Chrysopherla carnea – not present in Australia
4) Mallada signata

White Fly Predators

1) Amblyseius swirskii – not present in Australia
2) Transeius montdorensis (AU)
3) Encarsia formosa
4) Eretmocerus eremicus
5) Nesidiocoris tenuis

Two Spotted Mite (TSM) Predators

1) Neoseiulus californicus
2) Phytoseiulus persimilis

Microbial Agents

Microbial agents may colonise roots or leaves to combat pest and disease, and to enhance plant vigour by signalling and raising the defence mechanism of the plant.

Entomovectoring is an innovative technology using pollinators to deliver microbial formulations to flowering crops.

A retrofitted inoculum dispenser is attached to commercial hive.

Bees have a highly developed social structure and require UV light for navigation which can be limited under diffused plastic greenhouse covers.

6) Chemical Controls

This is an important and integral part of the equation and it is important to use the least toxic option where possible to avoid disruptions to established BCA’s in crop.

A grower needs to know the specific mode of action of the chemical used and its direct affect upon the pest and/or disease.

Unexpected Observations

1) Trichomes and how some beneficial don’t like hairy leaves like raspberries
2) Pollen supplements required to keep beneficial insects sustained and alive even when there are no pests to eat.
3) Auto-dissemination
4) Reduction in number of instars in protected crops
5) Spotted Wing Drosophilia has inadvertently lead to increase in hygiene protocols
6) Gene editing of insects

Key Learnings

1) Timing
2) Balance
3) More focus on plant disease bio control agents required
4) Biologicals need to be competitively priced
5) Controlled release sachets
6) Bio-stimulants

Wade Mann’s full Nuffield Report is available at www.nuffield.com.au

Wade Mann, Roses 2 Go Pty Ltd Phone 0404 913 209 wademann125@gmail.com