By Grethe Bestbier
A facility at Welgevallen Experimental Farm in Stellenbosch is buzzing with life. Here, thousands of moths, worms, flies and other insects are bred every year to ensure that the industry has somewhere to turn to for applied research in the area of pest control.
The start-up days
The insectary finds its beginnings in 2012 after the completion of a pilot project on the management of codling moth (CM) run by Matthew Addison, Hortgro Science Crop Protection Manager. This major pome fruit pest could be sterilised and released to control populations in Western Cape orchards. Hortgro Pome funded the development of the initial phase of a commercial insectary valued at R4,6 million.
Named Entomon Technologies (Pty) Ltd. the insectary mass produced sterilized codling moth colonies as part of area-wide integrated pest management (IPM) tool for the pome fruit industry. In December 2014 Hortgro donated the facility to the Stellenbosch University’s (SU) Faculty of AgricScience for further pest management research. This came after a decision was made by the Hortgro Pome board not to invest beyond the initial phase of development as there was not enough of an appetite for the technology.
Hortgro Science’s Dr Daleen Stenekamp and Terence Asia managed the facility, until Stenekamp resigned last year, leaving Asia in charge. Asia remembers the Entomon-days well when sterilised moths were produced daily and released in different areas such as Grabouw, Worcester and Ceres.
“Sterile Insect Release (SIR) is initially more expensive if it is used in combination with mating disruption,” says Asia about why it was halted. “Another factor was that SIR is a long-term strategy and sometimes farmers need quick results.”
What is the facility used for now?
Currently, the facility is in the hands of the SU Faculty of AgriScience. It is used for IPM research by the Department of Conservation Ecology and Entomology with the focus on arthropod pest management in deciduous fruits, citrus, and sugar cane. Previously, this type of research had to be conducted in inadequate laboratory facilities which limited the growth and development of strategic research.
Asia says that in terms of pest control, the farmer’s number one priority is to control the insects. For the entomologist, however, there are other focuses: investigating the insect’s lifecycle, its preferences, its triggers, what it does, when and why?
“To understand the insect better, is the main priority for us,” says Asia. “If you understand the pest you can control it.”
According to Dr Pia Addison, senior lecturer at the Department of Conservation Ecology and Entomology, IPM research conducted at the insectary involves exploring alternate methods of pest control, with reduced synthetic pesticide inputs. The facility itself is used for large scale production of various insect colonies. These colonies include codling moth, Lobesia, fruit flies, wax moth and mealybug, which is produced all year round at the insectary. The overall aim is to further develop expertise in key strategic areas of IPM and mostly, to develop sustainable IPM practices, says Addison.
Value to industry
The insectary is important to the entire deciduous fruit industry. The facility also benefits students. It gives them a hands-on understanding of the insect during its different life cycles. Once an insect species is successfully produced, several applied research projects can take place, for example, research on determining life table parameters, physiology, taxonomy and assessing biological control agents.
The facility has many positive outcomes. It provides laboratory space to meet the requirements of applied research projects. The codling moth colony allows for the early development of EPNs (entomopathogenic nematodes), researching mass culture methods and biological control agents. The weevil colony enables the development of entomo-pathogens under laboratory conditions and field applications. The fruit fly colony (Medfly) assesses various field-collected EPNs and EPF (entomopathogenic fungi), and this research is now ready for field application.
Creating an enabler
The key value of the insectary is that it is an enabler, says Hugh Campbell, Hortgro Science’s General Manager. “It enables research on insects through its different life stages. For example, previously researchers could not sustain a colony of snout beetle so they were forced to do their research in the field which limited the type of research that they were able to conduct. Daleen developed a technique to sustain them in an insectary which, in turn, opened up the opportunity to work on different life stages of snout beetle. What has actually happened is that we have had an expert who has developed the expertise to maintain a colony. Previously each researcher tried to develop and maintain a colony – often without success.
“Entomon, which produced codling moth on a continuous basis provided constant material at all the different life stages, which in turn, provided material for the entomopathogenic research by Dr Antoinette Malan. The initiative was almost entirely funded by Hortgro. We employed the staff and provided the funding for the maintenance of the facility. One or two other industries made very small contributions – for selected insects. Without Hortgro employing the people nothing would have happened,” says Campbell.
According to Matthew Addison, the focus is on research and the development of biological control agents (e.g. mealybug parasitoids), as well as sterile insect production. “The facility is unique in that it is a functional large-scale insectary, but it is up to the industry to determine how well it is utilized,” he says. Asia himself has high hopes for the facility.
When asked what his dream would be for the facility if he had unlimited resources, he excitedly answers: “More insects.” “I mean a greater variety of insects. Every insect has its own way of doing things.” Earlier, they had a problem with Lobesia moths. The moths were kept in bottles but would not lay eggs. What to do? They put the bottles in natural light and voila everything functioned normally. “A new piece of information was discovered. It’s the small things that make my work interesting.”
No pun intended.
Pictured above Terence Asia and Dr Pia Addison.