"Researchers have been trying to develop biopesticides for about 50 or 60 years and there was quite a lot of interest in the 1990s.
"The problem was the products on the markets were very expensive and their performance was not particularly good.
"It was not surprising they didn't have a particularly good adoption and uptake by growers.".
However, there has been more investment and interest in research and development since then, and more effective products have been made available.
"Growers are now looking at them again" she said.
"They are a good alternative to synthetic chemicals.
"We are not suggesting those products take over or replace synthetic chemicals. They just give more options to control pests and diseases and they can reduce chemical [usage].''
She said consumers were increasingly uncomfortable with synthetic chemical inputs such as pesticides.
In addition all industries were having to look at using products that were better for the environment, and more acceptable to the public.
"I have had a really good response, really positive, although some people are a bit sceptical.
"Growers are used to working with normal synthetic products, which are easy to use with really good knockdown effects".
Using biopesticides still required Growsafe or Applied Handler certification, and users needed to learn how to both store them and apply them within the correct temperature ranges.
Incorrect temperatures could kill the micro-organisms in the products.
In addition, some biopesticides could be used to complement synthetic products, would not harm beneficial insects and could also be used closer to harvest times.
However, they still needed to be applied with protective gear and kept in approved storage areas.
"It is important the growers realise just because they are a natural product, they still have be used properly".
She advocated common sense and to follow the regulations around biopesticide use.
Prof Stewart said she had received really good feedback from the presentations with many asking questions about what products were available and how to get hold of them.
While there were not that many registered for cropping systems at the moment, there would be more coming on to the market in the next five years.
"They are also giving organic growers more options as well" she said.