How biodegradable friendly capsules are helping combat cotton pests
August 1, 2023
That’s the reality in today’s modern and innovative Australian cotton industry.
Farmers are using Crop Capsules – a biodegradable, natural and chemical free alternative to tackle in-crop pest Silverleaf Whitefly, while caring for the natural environment and improving their farming practices.
But these aren’t your ordinary backyard wasps.
It’s hard to believe these tiny wasps, about the size of a breadcrumb, have a big impact. But Team Leader Adam Perkins says Crop Capsules are reducing the need to spray for Silverleaf Whitefly by more than 90%.
“There is no silver bullet for controlling Silverleaf Whitefly. But by using biological control and understanding the science surrounding beneficial insect behaviour, Silverleaf Whitefly can be controlled when the Crop Capsules are deployed early enough,” Adam said.
About 500 parasitic wasp larva are inserted into the capsule, which is made from corn starch and vegetable oil.
It is deployed into cotton fields where about 1-2 capsules are dropped every hectare across the entire cropping production. The capsules are geotagged and mapped, providing data to the farmer.
Within one to three days of landing in the field, the wasps hatch and reproduce, with the female laying her eggs inside the eggs of the Silverleaf Whitefly – paralysing them and preventing their growth and emergence.
“The capsules serve as a protective nursery environment for a very delicate, live, biological material that allows the wasps to hatch in a controlled way into the crop,” Adam said.
“The capsule will show signs of cracking within a few weeks with little remaining after 18 months’ time. It’s also geotagged so farmers and agronomists can check the effectiveness of pest suppression in and around the location where the capsule landed.”
The 2022-23 cotton season was the fourth year Crop Capsules have been deployed into cotton fields, with trials extending into canola fields to help suppress aphids.
In Australia, 97% of cotton farmers use integrated pest management systems to control harmful in-crop bugs.
Crop Capsules adds to that defence, biologist agronomist Olivia Bange said.
“The wasps distributed by Crop Capsules are supplementing a population that’s already present in Australia, but not as concentrated in a cotton crop,” Olivia said.
“It’s assisting in enhancing and expanding the population of a beneficial insect to control Silverleaf Whitefly.”