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A few years ago the breadfruit crash was seen as "serious" by Diana Ragone, director of science at the National Tropical Botanical Garden in Hawaii.
After a South Pacific Community workshop here last week, she said it had gone past being "serious".
"On some atolls now the people are seeing total dieback of the breadfruit trees, one hundred percent," she told AFP.
The single biggest killer is worsening inundations of atolls by sea-water -- a symptom of global warming and sea-level rise.
Shallow rooting breadfruit trees are also vulnerable to the increasing storms, Ragone said.
Two cyclones, Val and Ofa, have totally wiped out breadfruit trees in parts in Samoa.
Moreover the popularity of Western processed foods is taking people away from breadfruit and the trees are being neglected.
Genetic diversity is narrowing and in some places many varieties, each of which had local names, have disappeared.
Ragone said there was no prospect of the breadfruit tree becoming extinct, but the diversity was being lost, and so too a remarkable story behind the beautiful tree.
Breadfruit (artocarpus altilis) is a large, attractive and evergreen tree, reaching as high as 20 metres (60 feet) with a smooth, light-coloured bark and thick large leaves.
The fruit is large and starchy, produced, depending on the variety, once or twice a year. Some varieties fruit all year round. It is thought to have originated in the Moluccas, Philippines and New Guinea area with first domestication in the Bismarck Archipelago.
Ragone has documented in a study for the International Plant Genetic Resources Institute the way humans moved out into the Pacific, taking with them breadfruit, both as food and cloning material so that they could plant it in their new homelands.
The greatest diversity of seedless cultivars is in eastern Polynesia while Santa Cruz in the Solomon Islands has the greatest diversity of seeded plants.
Santa Cruz could represent the mother lode of the plant, but Ragone said fear of bio-piracy has led to the community there forbidding the export of plant material at all.
She accepted their concern but said in the wider global interest there needed to be a balance.
When Europeans came into the Pacific, breadfruit was a matter of astonishment, enhancing the notion of "paradise". Joseph Banks, a botanist with Captain James Cook's ship Endeavour, noted that to feed a generation and the next, all a man had to do was plant 10 breadfruit trees -- and that it would take only half an hour.
His report on the plant promoted the idea of taking breadfruit seedlings to the West Indies where it could be planted to feed the growing number of slaves there. A ship was sent to Tahiti and it was filled up with plants for the long voyage to the Caribbean.
It never made it for that ship was Bounty under the command of William Bligh -- and angry crewmen led by Fletcher Christian mutinied, throwing the plants overboard.
The rapid decline in recent years of breadfruit trees, and the narrowing of the variety, is christened as "Pingalap disease" for the atoll in Micronesia in which it was first noticed.
Ragone said the disease was more a condition than a pathogen, a combination of factors reducing the numbers of trees.
In the atolls of Kiribati, for example, the trees are not naturally occurring but grow well enough.
Most of the trees there now, around 40 years old, are increasingly "weak and feeble".
With junk food flooding markets, the need to carefully husband the trees has diminished.
"People have not been replanting," Ragone said.
"The genetic erosion of breadfruit can be attributed to environmental factors, changes in traditional lifestyles and the nature of the crop itself," she said.
They are prone to damage or destruction from high winds and salt spray and intrusion of salt water into the water table during storms is very damaging.
Replanting has not kept pace with the losses.
What Ragone calls a global trend toward warmer ocean temperatures and the increased likelihood of stronger storms spells disaster for the Pacific breadfruit.
SPACE.WIRE |