Papua New Guinea's coffee industry is crying out for help, after discovering an insidious pest in some of its most productive growing areas.

The coffee berry borer is a small beetle that has devastated coffee crops all over the world.

A smallholder grower in Jiwaka Province, one of the main growing areas, found the beetle on his block in February and brought it to PNG's Coffee Industry Corporation (CIC).

Dr Mark Kenny, from the CIC, has been leading the response to the outbreak and said the grower had thought the beetle seemed "unusual".

"It was not normal and he was suspicious that something was wrong with the coffee," he said.

Since then the CIC have found the beetle in several sites in PNG's Jiwaka and Eastern Highlands provinces.

They have put roadblocks in place to stop harvested berries from being taken outside the infested areas, but Dr Kenny said further measures were needed to limit the outbreak.

"If there is no control over this pest, then we stand to lose up to 80 per cent of the crop," he said.

"So it's quite a serious problem in the industry, and it needs everybody's effort to try to manage the problem."

A magnified image of the berry borer beetle, which has devastated coffee crops around the world. ( Courtesy: padil.gov.au )

Efforts 'will come to nothing without promised funding'

Dr Kenny said the agency had not received promised funding and did not have the resources to respond properly.

"[The PNG] Government has made some decisions to allocate some funds, but the funds have not come through," he said.

"All our efforts and the resources that we have already poured into this problem will come to nothing if no support is coming within the next couple of weeks, because we are stretched out."

The ABC tried to contact PNG's Agriculture Minister, Tommy Tomscoll, and the National Quarantine and Inspection Agency, to ask about funding for the borer outbreak, but did not receive a response.

Coffee growers like Belinda Brian could lose their crops if the beetle infestation grows.

Beetles 'eat their way inside the berry'

The coffee berry, or cherry, is the fruit of the coffee tree, which has the coffee bean inside.

The borer beetle makes a hole and goes inside the coffee berries, eats the bean and then lays its eggs.

"It completes its life cycle inside the bean, eats away the bean, that's why you don't get good beans out of it," Dr Kenny said.

"So once it's bored into the bean, it's as good as useless."

Coffee is grown in more than 60 countries and until this year PNG was one of only two unaffected by the berry borer.

The beetle has only been found on the blocks of smallholders — Papua New Guineans who have small numbers of trees — who grow 95 per cent of PNG's crop.

Peter Diria and Joe Alu burn infested coffee berries in an open fire. ( ABC News: Eric Tlozek )

Peter Diria was one of the growers whose block became infested with the beetle.

"We think we've lost close to 20,000 to 30,000 kina ($8,000-$14,000) in one year — the money we should have made," he said.

"The Government must investigate this sickness and help us, because it's the only cash crop we have in our country."

'This could cause social chaos'

Coffee is PNG's second-biggest agricultural export and much of the income goes directly to the hundreds of thousands of small growers.

Dr Mark Kenny from CIC and grower Bill Gardner. ( ABC News: Eric Tlozek )

Dr Kenny said if they lose money, it would affect the entire country.

"Families will suffer," he said.

"Not only that, but you will have a lot of mass migration into town, people looking for work.

"And you will have social problems in towns, in cities, because coffee is keeping them in the village."

A contractor sprays coffee berries against the beetle. ( ABC News: Eric Tlozek )

Specialty coffee grower Bill Gardner said while he did not think the beetle could kill the PNG coffee industry, "it could downsize a lot".

"When it's downsized like that, you have got to go through a transition period to create other income and other opportunities for people — which we haven't got readily available at the moment in this county," he said.

"I believe it will cause social chaos."

Mr Gardner runs a plantation and processing factory, and said he feared the outbreak could destroy operators like him.

"If we don't deal with the CBB and it becomes a major problem, it will put me out of business," he said.