Preserving Plant Germplasm: A ‘Noah’s Ark’ for Food in Taiwan

The film The Day After Tomorrow depicts numerous disasters resulting from climate anomalies caused by global warming. At the time the film was released there was debate about whether or not this could happen, but today the scientific community believes that in the long term the possibility of global catastrophe is real. However, even before such scenarios play out, rising temperatures are threatening the growth of food crops, and countries around the world are establishing germplasm banks to preserve the foods that we find on our dining tables.

Taiwan's National Plant Genetic Resources Center stores germplasm of native crops including paddy rice, millet, and other grains. The center also selectively breeds temperate-zone fruit tree varieties, and has successfully cultivated them in Taiwan's plains. There are hopes that in the future Taiwan can become the southernmost center for the preservation of temperate-zone fruit tree germplasm.

Meanwhile, the World Vegetable Center, located in Tainan's Shanhua District, is a "Noah's Ark" of vegetables for the planet, preserving the world's largest public collection of vegetable germplasm. Institutions such as these have made Taiwan into a bastion of gene conservation for foods that are tolerant of adverse conditions.

Data published in 2022 in the Sixth Assessment Report of the United Nations’ Intergovernmental Panel on Climate Change indicates that the increase in global temperature is accelerating. Experts and scholars warn that global warming will lead to extreme weather and there will be more natural disasters including heatwaves, flooding, and cold snaps as well as greater damage from pests and diseases, thereby impacting the growth of agricultural crops and potentially causing shortfalls in food supplies.

Warren H.J. Kuo, professor emeritus in the Department of Agronomy at National Taiwan University, says that when that time comes food prices will rise and there will be a need for plant varieties that are adapted to the new environment. These new varieties will be bred selectively from materials held in germplasm banks.

Kuo says that farmers have been setting aside seeds for later use for 10,000 years. Farmers have always selected seeds from the best-performing plants as the basis for breeding new plants. However, unlike traditional varieties, which are genetically diverse, the improved varieties supplied by commercial seed companies and plant nurseries have a high degree of "purity," with little variation between seeds, so that if the environment changes dramatically the crops may be unable to adapt to the new circumstances.

Nonetheless, in an age of profit maximization, most farmers have given up using their own local seeds and choose instead to cultivate commercially bred vari­eties, thereby losing the opportunity for selecting and preserving seeds with novel genetic characteristics. This problem is even more challenging in the context of global climate change.

A "Noah's Ark" for crops

As early as the 1970s many agricultural experts noticed that the proliferation of commercial plant vari­eties was leading to a loss of genetic resources. They advocated for the establishment of germplasm banks to preserve the seeds of varieties that farmers have given up cultivating, so that in the event of major disasters, these could provide needed sources of food during post-­disaster reconstruction.

Data from the academic community shows that there are some 1,750 germplasm banks across the globe. Norway's Svalbard Global Seed Vault, known as the "doomsday vault," stores seeds from cereals and other crop plants from around the world. In Taiwan, the World Vegetable Center (WorldVeg), located in Shanhua District, Tainan, began operations in 1973, and has the largest collection of vegetable varieties held by any non-profit organization in the world.

In 1993 Taiwan also established the National Plant Genetic Resources Center (NPGRC) in Wufeng District, Taichung, to preserve Taiwanese crops including paddy rice and other grains and staples. Both of these Taiwan-­based institutions have deposited duplicates of their germplasm in the Svalbard Global Seed Vault as part of the preservation of the world's edible plant species.

The National Plant Genetic Resources Center at Wufeng in Taichung stores "seeds of hope" for Taiwanese crop varieties. (Kent Chuang)

Preserving temperate-zone fruit trees

In Taiwan, with its abundance of farm produce and seafood, it is difficult for people to imagine food disappearing from their dining tables, but there is nonetheless an ongoing food crisis.

"Taiwan relies on imports for 70% of its food crops, and has quite a low level of self-sufficiency." Warren Kuo notes that in earlier times farmers in Taiwan grew broad beans (a.k.a. faba beans), speckled kidney beans, and mung beans, but these are not widely cultivated today, and the mung beans we love to eat in summer are imported from Indonesia and Myanmar.

After the destruction wrought by Typhoon Morakot in 2009, many indigenous communities stopped planting millet, and it became impossible to find seeds of their original local varieties. Fortunately the US National Plant Germplasm System had preserved 96 millet varieties from Taiwanese indigenous communities, and it was through the importation of seeds from the US that millet could once again be cultivated in these areas.

The NPGRC is part of the Taiwan Agricultural Research Institute (TARI) of the Council of Agriculture. It is tasked with preserving the germplasm of Taiwanese crops in order to provide "seeds of hope" to enable cultivation of these crops to be resumed following disasters.

Visiting the NPGRC in late March, we see ­workers operating cultivators to prepare the soil of several paddy fields, where they will transplant rice seedlings for field trials.

The center's clonal germplasm repository, which is two kilometers away from the seed storage facility, is also used for trial cultivation of various varieties of millet as well as peach, Japanese apricot, and cherry trees that have a low chilling requirement (the number of hours at low temperatures needed to trigger winter dormancy).

"In most people's minds, Japanese apricot trees need to be grown in the mountains, but the elevation here in Wufeng is only 89 meters above sea level, yet most of the trees are flowering well. There is one tree that hasn't blossomed so far, indicating that the winter here is not cold enough for it, making this variety unsuitable for lowland cultivation." Huang Chun-che, assistant researcher in TARI's Division of Plant Germplasm, leads us through the repository's fields and orchards as he explains how he and his colleagues assess the suitability of crop varieties for particular geographic and climatic conditions.

In another area there are peach and nectarine trees with low chilling requirements. Pointing out one of the trees, he explains, "This one has barely produced any buds, which shows that the conditions this year have not been right for it. But we will still take cuttings back to the lab for low-temperature experiments to determine its thermal tolerance," says Huang. In another area, peach cultivars imported from Florida are being grown. They have adapted well to conditions in Taiwan.

Taiwan's special characteristics

Senior agronomist Chen Shu, director of the Division of Plant Germplasm, notes that Taiwan straddles the Tropic of Cancer, placing it in both the tropical and subtropical zones. Thus not only can tropical fruit trees be grown here, but temperate-zone fruit trees are also being successfully cultivated, giving Taiwan a comprehensive range of fruit tree varieties. She says with confidence: "In the future we can become the southernmost center for the preservation of temperate-zone fruit tree germplasm."

In Chen's assessment, crops grown in Taiwan face the dual challenges of high temperatures and scarce water resources. When the supply of water for irrigation is unreliable, production of paddy rice, which requires large amounts of water, faces a crisis. Therefore, the goal of selective breeding is to develop crops that are resistant to drought, diseases, and pests.

The NPGRC collects Taiwan's upland dry rices and wild paddy rices, which have poor palatability, meaning that farmers are unlikely to continue growing them, but which are native varieties that are resistant to pests and diseases and can survive both drought and flood conditions. "They have many valuable characteristics, and through repeated crossbreeding and selection there is a chance that we can produce new germplasm that is adaptable to the environments of the future."

Currently the NPGRC is successfully preserving over 10,000 Taiwanese varieties of paddy rice, including the world's southernmost Japonica rices, flax (a crop that has been abandoned by Taiwanese farmers), and more than 100 varieties of millet (an essential element in the culture of Taiwan's indigenous peoples).

Paddy rice germplasm is also provided to other countries for cultivation; for example, the genetic material for many varieties of paddy rice grown in India has come from Taiwan. Taiwan has also sent paddy rice germplasm to the International Rice Research Institute in the Philippines for shuttle breeding.

The NPGRC building, a two-story-high marble-faced structure, holds germplasm for more than 100,000 varieties of grains, vegetables and other crops in short, medium, and long-term storage.

The powerful earthquake that struck Taiwan on September 21, 1999 did great damage in Wufeng District, but Chen Shu says that only a single storage rack in the gene­bank was bent out of shape, and "not a single seed was lost."

World Vegetable Center

The World Vegetable Center (WorldVeg), founded in 1971 as the Asian Vegetable Research and Development Center and renamed in 2008, is an international agricultural research institution that holds the most complete collection of vegetable crop germplasm in the world. World­Veg notes that it is located in Taiwan because the island spans both tropical and subtropical zones and has great biodiversity as well as advanced agricultural technology, with the Chiayi–Tainan Plain being especially suitable for farming. Researchers gather germplasm from around the world and deposit it in the genebank that is at the heart of WorldVeg's operations.

When we arrive at the 116-hectare WorldVeg site, some of the broad expanse of farmland outside the main gate is lying fallow while some is planted with vegetables including tomatoes, eggplants, and hyacinth beans. The colorful variety of crops from all the world's inhabited continents delights the eye.

In an open area in front of the genebank building, staff are in the process of separating the seeds of different varieties of eggplant from the flesh. Indoors, another team is preparing seeds for storage.

To date, WorldVeg has amassed a collection of 65,000 accessions of over 330 plant species from 157 countries. The institution supplies germplasm to research institutes and individuals free of charge, and has sent out over 700,000 germplasm samples to more than 204 countries and territories around the world. Of these, a large proportion have been for tomatoes, mung beans, and chili peppers, with tomatoes accounting for a third of all samples. One half of all the tomatoes grown in Tanzania can trace their origins back to WorldVeg.

Tomatoes, mung beans, and chili peppers

Chan Yan-kuang, principal research assistant for genetic resources and seed at WorldVeg, says that the tomato is one of the most commonly consumed vegetables in the world. Tanzania's native tomatoes unfortunately had a high rate of losses during transportation from production areas to consumer markets, so World­Veg, which has a regional base in Arusha, Tanzania, transferred tomatoes bred in Taiwan to the facility for trial cultivation. Ultimately varieties suited to local conditions were selected and their use was promoted to farmers. Today not only is Tanzania self-­sufficient in tomatoes, they have become an important cash crop for local farmers.

Another example is bhut jolokia, an especially hot chili pepper that is popular in Africa. The original bhut jolokia varieties have poor disease resistance, so breeders at World­Veg selectively crossbred them with disease-­resistant chilis and selected a bhut jolokia variety that is both very spicy and has good genetic resistance to disease. This new variety was brought back to Africa for cultivation.

In recent years agricultural technology has become widely used in S outheast Asia, and local varieties are rapidly being lost. In 2022 WorldVeg and the Ministry of Foreign Affairs launched the Taiwan–Southeast Asia Vegetable Germplasm Initiative, under which germplasm from 183 plant species from South and Southeast Asia that was previously collected and stored at WorldVeg is being recultivated in their countries of origin, to make this resource available to local plant breeders.

A report published by the United Nations’ Food and Agriculture Organization states that in the century from 1900 to 2000, biodiversity in food crops fell by 75%. Through variety preservation, germplasm banks offer a "tailor-made insurance policy" against crop failures and food crises. Nevertheless, if on this basis we continue to ignore the scale of the impacts of global warming, there will be no end to the threat of disaster for the human race.