In a secure, temperature-controlled vault in Fiji’s capital of Suva, stacks of tiny vials hold several plantations-worth of sprouting plants.

The dazzling display of banana, taro, breadfruit, yam, and other seedlings represents a back-up collection of the most important varieties of crops in the Pacific region.

Of the 2,200 varieties of 18 crops, many are the last of their kind.

They’ve been collected and maintained for 25 years at the Centre for Pacific Crops and Trees (CePaCT) — the Pacific’s main regional gene bank — to preserve agricultural plants for future generations.

Much like the famed “doomsday” seed vault in Svalbard, CePaCT is a last line of defence in case species or varieties are lost over coming decades.

But unlike Svalbard’s vault, CePaCT focuses not on storing seeds, but on propagating (and re-propagating) plants as tiny bottled-up sprouts.

It’s intensive and complicated, but necessary to ensure potentially vital crop varieties survive.

Here’s what happens inside the Pacific’s most important gene bank.

An immense collection of clippings

The woman who has spearheaded the project here in recent years is Logotonu Meleisea Waqainabete, program leader for genetic resources at the Pacific Community (also known as SPC).

CePaCT will be incredibly important as the climate continues to change and as pests and diseases spread around a more globalised world, she says.

“Climate change … wipes away all these unique genetic resources that we depend on for our food needs.

Each of the varieties of the crop species stored here has adapted to different conditions over generations.

“There are many different sub-varieties of each and every kind of iconic species,” Ms Meleisea Waqainabete says.

For example, some that come from low-lying areas are more salt tolerant, while others are resistant to certain diseases.

She says having a carefully studied collection of crops with different abilities, flavours, or adaptations will be crucial for the coming century.

The plants in this facility are clippings, propagated and then re-propagated, again and again, using tissue culture.

“Tissue culture is just the science of growing one small piece of the plant in artificial media under very strict sterile conditions,” Ms Meleisea Waqainabete says.

Each cutting’s roots grow into a nutrient-rich gel. Under artificial lights, it lives in a semi-dormant state.

CePaCT also stores some seeds, but Ms Meleisea Waqainabete says many of the plants here are easier to maintain as tiny sprouts.

“Some of these crops don’t produce true-to-type seeds, and some of them produce seeds that are not viable.”

So instead, small plants and cuttings are shipped in from CePaCT’s 22 Pacific Island member nations.

And if a variety stored here in the vault is struggling out in the world, those member nations can also make a withdrawal from the gene bank.

“We also provide the same materials back to them,” Ms Meleisea Waqainabete says.

Having collections like this has already proved incredibly important for countries and farmers.

A fight against taro leaf blight

In the mid-1990s, a mould called taro leaf blight struck Ms Meleisea Waqainabete’s home country of Samoa.

It decimated the nation’s taro plants — a culturally important food security crop and Samoa’s main agricultural export.

“All of the Samoan varieties were susceptible,” Ms Meleisea Waqainabete says.

She watched as the country’s taro farms, including her family’s, suddenly stop producing.

But thanks to the efforts of plant scientists, other varieties more tolerant to the mould were crossbred with Samoa’s taro to make a new resistant strain that revitalised the industry.

Ms Meleisea Waqainabete points to a row of taro plants, representing the original Samoan varieties and several others from across the region, including Indonesian lines that withstand taro leaf blight.

“These varieties were bred together with some more Pacific lines, including some lines from [the Federated States of Micronesia] and Palau,” she says.

“And that’s how Samoa is able to eat taro now.”

Even better, she says today’s Samoan taro tastes the same as the original varieties, thanks to these cross-breeding efforts.

During the response to taro leaf blight, hundreds of varieties of taro from across the Pacific were sampled, catalogued, and stored.

This led to the formation of CePaCT, which has since operated as a centralised collection house for the region’s varieties and a hub for exchanging and improving crops.

A global exchange network

CePaCT is one component of a worldwide network of gene banks that are helping to find and share more resilient crops like disease-resistant taro varieties.