New "attract and kill" trap technology has helped a greenhouse hydroponic strawberry farmer in Port Macquarie to control a pest he had not previously seen.

"Our first summer crop of strawberries had just started when I noticed small black beetles piercing ripe fruit," strawberry production manager at Ricardoes tomato and strawberry hydroponic farm, Rob Southey, said.

NSW Department of Primary Industries (DPI) identified the insect as Carpophilus beetle, generally not considered a pest in strawberries in the Port Macquarie district or more widely, but a major insect pest of ripe fruit, mostly in stone fruit orchards.

Mr Southey faced a dilemma; there were no registered insecticides for control of Carpophilus beetle in strawberries in NSW.

Even if registered insecticides had been available, Ricardoes had adopted an Integrated Pest Management (IPM) program for both tomatoes and strawberries and were reluctant to use pesticides.

Mr Southey said infestation of the strawberry crop could not have come at a worse time.

The plantings were timed to take advantage of the January holiday period when families could enjoy a back-to-nature experience by walking through the greenhouses, picking and eating fresh ripe strawberries.

"Applying any pesticide was not an option for us," Mr Southey said. "We had to find an alternative."

NSW DPI horticulturist, Lawrence Ullio, suggested new attract and kill funnel traps, now widely used in fruit orchards around the Sydney Basin and the Goulburn Valley in Victoria to control the pest.

The traps have done away with the need for many fruit growers to apply insecticides.

Previously, insecticides were applied to ripening fruit on trees, and on fallen fruit beneath trees, as the main control measure.

Mr Ullio, with the assistance of Dr Mofakhar Hossain, research scientist with the Victorian Department of Primary Industries, helped develop a management program to control the beetle at Ricardoes, using both traps and improved farm hygiene.

Only two traps were required, placed five to 10 metres from the farm’s two greenhouses and one metre off the ground.

A synthetic pheromone and synthetic odour of ripening fruit were placed inside the traps, with a small pest strip at the bottom.
Beetles were attracted by the smell of fruit and climbed into the trap, to be killed by the pest strip.

"We were very impressed with the results," Mr Southey said.

"The first week we were catching several matchboxes full of beetles every few days.

"By the third week the population was reduced to such a low number that we weren’t getting any more fruit damage."

Ricardoes strawberry farm will continue to use the traps during next season’s crop.

They grow their strawberries on an A frame system using white PVC pipes to support the plants, sandwiched within a rockwool slab, placed in each hole.

The nutrient solution is regularly monitored for pH, salt build up, temperature and nutrient levels.

The two greenhouses hold 80,000 plants and each can produce more than 35 tonnes of fruit per crop.

The farm is trialling different strawberry varieties from Australia and the US, with the aim of producing fruit for eight to 10 months of the year, to take advantage of farm gate sales and the "pick your own fresh fruit" experiences that consumers want.

NSW DPI provided the traps to Ricardoes as part of the CleanFresh pesticide monitoring project, which helps growers reduce use of pesticides on fresh fruit and vegetables.

The traps are part of a commercially available kit of five, which cost $473.

Contact Lawrence Ullio, Flemington, (02) 9735 9600, lawrence.ullio@dpi.nsw.gov.au

Further reading

Greenhouse horticulture