Millennium Seed Bank building at Wakehurst
RSS Feed for the blog Millennium Seed Bank blog

Millennium Seed Bank blog

Welcome to the Millennium Seed Bank blog. There is a lot going on behind the scenes at Kew's Millennium Seed Bank (MSB) - not only here at Wakehurst but also with our partners all over the globe. We will be blogging about our seed collecting trips, local events, research projects and discoveries as well as everyday goings on.

We currently have seeds from more than 30,000 species of wild plants in long term storage and continue to receive seed collections from all over the world. It is an amazing place to work and we hope to share our passion for seed conservation with you via our blogs. 

Find out more about Kew's MSB | Adopt a seed for £25 or save a species outright

Seed collecting workshop in Vietnam

By: Elinor Breman - 10 Feb 2014
Elinor Breman, Species Collections Support Officer at Kew’s Millennium Seed Bank (MSB), reports on a training workshop in Vietnam that brought partners from across Asia together to learn about collecting, handling and banking the seeds of their crop wild relatives.
  • Close

Global food security

Global food security is of growing concern in the light of population expansion and climate change predictions. There are around 7,000 plant species used as food crops globally, but just 12 of these account for roughly 80% of global consumption.

Conserving the genetic diversity of the most important food plants is vital for breeding crop plants that are able to face future environmental challenges. The Millennium Seed Bank of the Royal Botanic Gardens, Kew and the Global Crop Diversity Trust have joined forces in a project to collect, conserve and make available for use the genetic diversity in the wild species related to major food crops.

This project - Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Crop Wild Relatives (CWR Project) - supports national institutes around the world in collecting and safeguarding priority crop wild relatives. Seed Collecting Guides have been developed to provide collectors in the field with as much information as possible about these wild plants, so that they are able to find them and collect their seeds.

The Vietnam Seed Collecting Guide contains information on 17 different crop wild relatives, including distant cousins of banana, apple, pigeonpea, aubergine, rice and sweet potato. The collecting guide contains a description of what the target plants look like, when they are going to have ripe seeds, where they are found, and also has photos to help identification.

Vietnam Seed Collecting Guide: page for banana relative Musa itinerans.

Vietnam Seed Collecting Guide: page for banana relative Musa itinerans.

This wild relative of banana is found in evergreen forests and ravines. Unlike cultivated bananas, it has large seeds (up to 7 mm) and the skin of the fruit is pink rather than yellow.

Training in Vietnam 

Members of RGB Kew’s Seed Conservation Department headed to Hanoi in Vietnam to lead a training course for delegates from Indonesia, Malaysia, Nepal and Vietnam.

The week-long training course on collecting, handling and long-term conservation of seeds of wild species related to crops was hosted by the Vietnamese Plant Resources Center and funded through the Sfumato Foundation. It provided a thoroughly enjoyable and educational introduction to the world of wild species seed conservation, highlighting the difference between this approach (wild species, long-term conservation) and that of agricultural genebanks (cultivated species, short-term conservation).

In the lecture room, the science behind long-term seed conservation was explained, enabling participants to understand how factors such as temperature, seed moisture and seed development would affect the longevity of seeds in storage. Fieldwork planning was outlined, detailing how to target species and areas for collection, the genetic basis of sampling strategies, and how to use seed collecting guides. 

In the field 

We then moved from the lecture room to the field to put the theory into practice. In the Ba Vi Mountains National Park, to the west of Hanoi, participants were able to:

  • assess the quality of potential seed collections
  • choose appropriate sampling strategies
  • make collections of seeds, herbarium specimens and associated data
  • choose appropriate post-harvest seed handling methods 

Putting theory into practice - fieldwork in the Ba Vi Mountains National Park: negotiating the terrain; making a herbarium voucher; collecting target species.

Putting theory into practice - fieldwork in the Ba Vi Mountains National Park: negotiating the terrain; making a herbarium voucher; collecting target species.

The many challenges facing seed collectors in the field soon became apparent. Finding a target species when it is growing in inhospitable terrain or is widely dispersed is not always that easy. When you have found it, a plant may have many fruits on it, but how many seeds are in that fruit, and how many of those seeds are fully developed and likely to germinate? The importance of checking seed viability using a seed cut test was demonstrated, together with seed number calculations which determine whether an adequate sample can be collected from the target population without impacting on the wild population’s survival.

The practical session continued the following day when the material collected in the field was cleaned and counted at the Plant Resources Center. Here a variety of species requiring different cleaning techniques were used, and different winnowing methods were shared by participants.

Photo of seed cleaning at the Plant Resources Center, Hanoi

Seed cleaning at the Plant Resources Center, Hanoi

Local culture

While in Vietnam our hosts from the Plant Resources Center ensured that the course ran smoothly, that everyone was looked after and that we sampled Vietnamese culture. This included introducing participants to the wonders of Vietnamese cuisine, and organising an optional excursion after the course had finished to the World Heritage site, Halong Bay.

Meal times and the excursion proved an invaluable time for networking among participants. At the end of the week, they left not only with their newly-acquired knowledge of seed collecting, handling and long-term conservation of wild species, but also with new friendships and an air of excitement about participating in the Crop Wild Relatives Project.

Photo of participants and trainers at the Vietnam conference

Participants and trainers on the training course, Hanoi, Vietnam (Photo: Plant Resources Centre, Vietnam)

Testimonials from course participants

  • 'For me, this course is really beneficial and gives me such an unforgettable experience. It deepens my understanding of managing and maintaining our genebank.'
  • 'Many thanks for your lectures, your experiences and your hospitality.'
  • 'I express all my admiration for Kew who organised this course.'

- Elinor Breman -


Related links

0 comments on 'Seed collecting workshop in Vietnam'

Seed Collecting in the Northern Cape

By: Paul Smith - 30 Jan 2014
Read the diary of Dr Paul Smith, Head of Kew's Millennium Seed Bank, as he and colleagues undertake a seed collecting expedition in the Northern Cape region of South Africa.
  • Close

Day 1: January 20 - Tswalu Game Reserve

We arrived here yesterday after two days driving from Cape Town (1,400 km). A beautiful place but dry and very hot. The temperature was expected to climb to the mid-forties today. We therefore planned do our seed collecting in the early morning and late afternoon/evening, avoiding the hottest part of the day.

The seed collecting team is made up of Livhu, Sarah and Zoleka from the South African National Biodiversity Institute (SANBI), and Jonathan and myself from Kew. Today we were joined by Corne, our local guide.

Livhu had already checked our seed list against the plant checklist for the Reserve, and found around 50 species that we don’t have in the Millennium Seed Bank. The trick, however, is to find the plants in seed.

Our first stop was the rocky hills that are found in the east of the Reserve. The dominant vegetation type in this part of the Kalahari is Acacia wooded grassland – mainly Acacia mellifera, A. erioloba and A. hebeclada. Rhigozum trichotomum is another important woody species. The grass layer is largely made up of Stipagrostis, Eragrostis, Anthephora, and Enneapogon desvauxii in the calcareous areas.

View of Tswalu Game Reserve, Northern Cape

View of Tswalu Game Reserve, Northern Cape

Here in the hills we were able to make a large collection of Andropogon gayanus, a grass that is used in C4 photosynthesis research, and which was on our hit list. An unexpected treat was seeing mountain zebra galloping past as we made our collection.

From the hills we went down on to the plain where we were able to collect three other species, including Ehretia rigida, a shrub used for medicinal purposes. By this time it was midday, and we were pretty dehydrated so we headed back to camp for lunch.

After lunch we were joined by Sam and Zandri, two local researchers who had offered to show us the major habitats in the park. We climbed aboard their 4 x 4 to tackle the Kalahari dunes, and drove from east to west – a full transect of the park – stopping in each habitat to look for seeding species. We found a number of plants that we are after but, unfortunately, none was in seed. Their localities were noted for future visits however. Thus ends our day in Tswalu. It’s a lovely place that the team will come back to. We left a few collecting bags with our friends there.

Day 2: January 21

A very long drive today (1,100 km) in which we traversed the Northern Cape pretty much from top to bottom. Our route took us past towns with evocative names such as Hotazel and Pofadder. Sarah and I shared the driving. Spectacular scenery and empty roads made it a pleasurable experience. Our destination was Nieuwoudtville, the bulb capital of South Africa, and home to SANBI’s newest botanic garden, 'Hantam'.

Photo of sign to the charmingly named town of ‘Hotazel’ in the Northern Cape

Sign to the charmingly named town of ‘Hotazel’ in the Northern Cape.

We arrived in Nieuwoudtville at about 7pm, found our B&B, and had an early night.

Day 3: January 22

We teamed up with Hantam staff first thing this morning, led by Eugene, the curator here. Also joining us were Arika, Raymond, Gershwin and Mercia. Hantam Botanic Garden is an 8,000 hectare nature reserve comprising parcels of richtersveld, karoo and fynbos vegetation. This morning we headed out to the Hantam fynbos, our main target being the endangered species Leucadendron remotum. We were delighted to find it in fruit, but found that most of the cones were infested with insects. Fortunately, Eugene’s team had noticed that some of the seeds on the ground under the shrubs were intact. We spent about three hours at this site collecting the Leucadendron and several other species.

Photo of the endangered Leucadendron remotum

The endangered Leucadendron remotum: most of the fruits were infested with insects

After lunch, we moved to a different part of the fynbos, looking for the wild ‘rooibos’ (Aspalathus linearis) from which the famous tea is made. Unfortunately, the plants were still in flower, and there were no seeds to be seen.

Photo of Sarah and Eugene with the wild ‘rooibos’ tea plant, Aspalathus salignum

Sarah and Eugene with the wild ‘rooibos’ tea plant, Aspalathus linearis

Further on we found a vlei and stream where we were able to make five good collections that included two Crassula species and a Juncus (rush). By this time it was 6.30pm, and time to head for home.

Day 4: January 23

Today we went out to one of the areas of Hantam Karoo vegetation. We were amused to see our Hantam colleagues in the car ahead suddenly screech to a halt then all climb out on to the car looking in one direction like a family of meerkats. They had spotted a spitting cobra in the road.

At our first collecting site, we collected several succulent species from the family Mesembryanthemaceae (Aizoaceae). Many of these plants produce anthocyanins – red pigments – to protect them against the strong sun. They reminded me of the most intricate of Turkish rugs. These plants are difficult to identify to species, and our collections will go to specialists who will be able to name them for us. They are easy to collect, however, with each capsule containing up to 40 seeds.

Photo of a carpet of succulent plants from the family Mesembryanthemaceae (Aizoaceae)

A carpet of succulent plants from the family Mesembryanthemaceae (Aizoaceae)

In the afternoon, we walked down into a nearby gorge where there is a seasonal stream (dry at this time of year). Here we were keen to collect seeds from two tree species – the Namaqua fig (Ficus cordata) and the silky wing pea, Wiborgia sericea, the latter being a Cape endemic. We were able to collect lots of seeds from the wing pea but our initial investigation of the fig revealed no fruit on the tree. However, when we looked on the rocks below, we found large drifts of seed in the rock crevices, and were able to collect these. We made several other collections in the gorge, including Galium tomentosa (a climber) and a white flowered Salvia species.

Day 5: January 24

The last day of our trip, sadly. We headed back to Cape Town via the Bottekloof Pass, the Cedarberg mountains and Clanwilliam. Awe-inspiring scenery, particularly the Cedarberg with its towering sandstone cliffs and buttes, looking like something out of a cowboy movie. The Cedarberg is home to the highly threatened Clanwilliam cedar, Widdringtonia cedarbergensis, a species we will have to come back for.

View from Bottekloof Pass

View from Bottekloof Pass

We got back to Cape Town by about 6.30pm. Our total tally over the past five days was 44 high quality seed collections, including both rare and threatened species. This is a tribute to the SANBI teams at both Kirstenbosch and Hantam, and I am extremely grateful for their hospitality and dedication.

- Paul -


Related links

1 comment on 'Seed Collecting in the Northern Cape'

Collecting for the National Tree Seed Project

By: Simon Kallow - 04 Dec 2013
As autumn turns to winter, Project Officer Simon Kallow looks back on the first season of seed collecting for the UK National Tree Seed Project.
  • Close

Prioritising ash seeds

The priority this year has been collecting ash seeds. This is mainly because of high profile threats to ash trees in the UK caused by the pathogenic fungi, Chalara fraxinea, including its sexual stage Hymenoscyphus pseudoalbidus - more commonly known as 'ash dieback'.

Ash is an important tree in the UK. It is the third most commonly recorded broadleaved species in the most recent Census of Woodlands and Trees, and the second most widely planted broadleaved tree. The area covered by ash in the UK, including hedgerows and small woodlands, is 180,000 ha. Furthermore, the value of ash trees for commercial use is £22 million per annum, though this is dwarfed by the social and environmental benefits estimated at £150 million per annum!

Ash trees also have high conservation value. They create a relatively open woodland canopy, allowing light to penetrate to the forest floor. This creates perfect conditions for a rich and varied ground flora to develop.

The leaf litter can also have a positive effect on the biodiversity of soil ecosystems by reducing soil acidity. Additionally, the long-lived nature of ash trees, especially when coppiced, provides niches for a rich diversity of animal, plant and fungal life. Many such species depend on ash trees for their survival.

Photo of open ash and oak canopy

Sunlight breaking through an ash and oak woodland canopy, Crab Wood, Winchester. (Photo: S.Kallow)

Genetic diversity of ash trees

Survival of ash trees in the UK also relies on the existing genetic diversity of ash trees. Resistance to ash dieback is thought to be present in a number of genes within the existing population. Therefore, preserving the genetic diversity of ash trees is the best way of supporting their overall survival: seed conservation is an excellent way of doing this.

So far we have collected roughly 160,000 ash seeds. The hope is that these seeds will provide an important resource for researchers and conservationists working to overcome these ecological threats.

Photo of ash seed in drying room

Seeds collected in the autumn are damp, so the seeds are currently being dried before being put into storage in the Millennium Seed Bank at -20°C. (Photo: S.Kallow)

Working with the Forestry Commission and Woodland Trust

It was clear from the outset that building a national tree seed collection was an ambitious commitment and was going to take more than a few workers from Kew so we enlisted the help of the Forestry Commission and the Woodland Trust. The Millennium Seed Bank is a partnership, working collaboratively across 80 countries to conserve and improve the use of seeds, so we have a good framework for working in this way.

The Forestry Commission has so far carried out 10 ash seed collections, focused in the east of England, central Scotland and in North Wales. It has also collected juniper seed in 19 sites in England and Scotland.

The Woodland Trust has recruited a team of devoted volunteers and collected hornbean and rowan seed at two of their ancient woodland sites. We have also been working closely with the Wakehurst Place Woodland Conservation team and together, so far, we have carried out ash seed collections at seven locations across the south and west of England.

Collecting seed in the field

How did we go about collecting ash seed? Firstly, we chose autochthonous populations, woodlands where trees have had a substantial history at a site over several generations. The theory is that in competitive ecosystems the trees we find are selectively adapted to local environmental conditions.

After choosing woodlands which are ancient or semi-natural, it was important that we gained the consent both of the landowner and also of Natural England, Natural Resources Wales or Scottish Natural Heritage who oversee the protection of these ecologically important sites.

When we got to a site, we checked the quality of seed to see if they were full and ripe. Then we aimed to collect seed from around 20 randomly selected trees.

Photo of a collector checking ash seed with a hand lens
Carrying out a cut test, whereby we cut and examined a sample of seed to work out the proportion of full, empty and infested seeds. Crab Wood, Winchester. (Photo: S,Kallow)

Lassooing seeds

The best method was to shake the high-up branches using a rope thrown up into the canopy. This released the seed which spun down onto a well-placed tarpaulin. When it worked this was a beautifully hypnotic sight, being surrounded by the twisting seed glistening in the low autumn sun.

Photo of ash seed being shaken free for collection

Shaking a branch to release ash keys during seed collecting. Highbury Wood, Gloucestershire. (Photo: S.Kallow)

Tagging trees

As you can imagine, things didn’t always work out like that. There were a number of challenges including steep slopes, dense woodland and, of course, the much anticipated October storm. So we used other techniques, such as using pole saws to prune-off reachable branches and remove the seeds.

We tagged the trees we collected from so that we can return to them if necessary. So if you see one of these tags on a tree – you’ll know that the tree is a parent of seed in the national collection.

Photo of tree tags used by the UK National Tree Seed Project

UK National Tree Seed Project tree tags (Photo S.Kallow)

Infested seeds

As a matter of course sub-samples are X-rayed to find the proportion of seed that is infested or dead, even after considerable effort to remove these seed. As you can see from these X-rays, ash seed play an important role in someone’s lifecycle - you can clearly see seed infested with invertebrate larvae. 

X-ray of ash seed
X-ray of ash seed (Photo: RBG Kew)

We’ve learned a lot over the course of these collections and it’s been great working with other organisations in order to make a real and lasting legacy for the UK treescape.

- Simon -



Related links

0 comments on 'Collecting for the National Tree Seed Project'

Orchid seeds – Nature’s tiny treasures

By: Wolfgang Stuppy - 28 Nov 2013
Orchids have the smallest seeds in the world and they produce millions of them, but why? Kew's seed morphologist Wolfgang Stuppy explains the clever survival plan that lies behind this seemingly wasteful strategy.
  • Close


Montage of many colourful orchids
Breathtakingly beautiful and vast in number - with more than 26,000 species, orchids are the largest family of flowering plants, not to mention the more than 100,000 hybrids humans have created. (Photos: Wolfgang Stuppy) 

The biggest seed in the world

Seeds come in all shapes and sizes. Famed for both its volume and suggestive shape, the seed (actually a single-seeded stone) of the Seychelles nut or double coconut (Lodoicea maldivica, Arecaceae) holds the unbeaten record for the world’s largest seed. It can weigh up to 18 kg and resembles something that, while bobbing in the waves of the Indian Ocean, gave sailors in the Middle Ages all kinds of, well, “seedy” ideas.

Photo of a man holding a big Seychelles Nut

Keith Manger, Lab Manager at the Millennium Seed Bank, proudly demonstrating the physical attributes of a Seychelles nut (Photo: Wolfgang Stuppy) 

Seeds like dust

At the other extreme of the spectrum we find the seeds of orchids. Famed for their beautiful and fascinating flowers, with over 26,000 species worldwide, orchids are the largest of all flowering plant families. What’s more, they also hold the world record for having the smallest seeds of all flowering plants. A typical orchid seed is merely the size of a speck of dust. 

Photo montage of orchid flowers and seeds
Top: Flower of Stanhopea Assidensis [= S. tigrina x S. wardii] and seeds of Stanhopea tigrina (0.66 mm long); below: flower and seeds (0.6-0.8 mm long) of the common spotted orchid (Dactylorhiza fuchsii) [Images from SEEDS – Time Capsules of Life by Rob Kesseler & Wolfgang Stuppy; Copyright Papadakis Publisher, Newbury, UK] 

Photo of seeds of the Wild Coco orchid (Eulophia alta)

Top: seeds of the Wild Coco (Eulophia alta), on a British one penny coin. Below: two seeds of the same species in the SEM (the scale bar shows half a millimetre; Photos: Wolfgang Stuppy) 

Tiny ones and not so tiny ones

To give an impression of the dimensions involved: a single capsule of the tropical American orchid Cycnoches chlorochilon produces almost four million seeds, and one gram of seeds of the southeast Asian species Aerides odorata contains 3.4 million seeds. At around 0.2 mm in length, Aerides odorata has the smallest seeds I have ever come across at Kew’s Millennium Seed Bank. According to the literature [Arditti, J. & Abdul Karim Abdul Ghani (2000) Numerical and physical properties of orchid seeds and their biological implications (Tansley Review No. 110). New Phytologist 145: 367-421], there are orchids with even smaller seeds. Those of the New Caledonian species Anoectochilus imitans are said to be the smallest of all, measuring just 0.05 mm in length. At a ‘gigantic’ 6 mm, the seeds of the lopsided star orchid (Epidendrum secundum) are allegedly the longest of any orchid. 

Photo of Acanthephippium splendidum and Aerides odorata seeds  

Top: two seeds of Acanthephippium splendidum measuring c. 3 mm in length. Below left: three seeds of Aerides odorata measuring c. 0.2 mm in length (the scale bar shows half a millimetre; Photos: Wolfgang Stuppy)


Photo of the flower of the bee orchid and seeds of early spider orchid
Left: flower of bee orchid (Ophrys apifera). Right: the seeds of early spider orchid (Ophrys sphegodes) measure a bit more than half a millimetre (c. 0.6 mm) [Images from The Bizarre and Incredible World of Plants by Wolfgang Stuppy, Rob Kesseler & Madeline Harley; Copyright Papadakis Publisher, Newbury, UK] 

Balloon travellers

The reduction in seed size and weight is mainly achieved at the expense of embryo and endosperm, the latter failing to develop in orchids. At the time of dispersal, orchid seeds consist of a spindle-shaped, wafer-thin seed coat that encloses an extremely small and simplified embryo in the shape of a spherical cluster of cells. Just one single cell layer thick, the seed coat (also called testa) forms a balloon around the embryo, a clear adaptation to wind dispersal.

Photo of Clowesia russelliana seed
A seed of Clowesia russelliana, an epiphytic orchid from tropical America, showing the thin, transparent seed coat enclosing a tiny spherical embryo (Photo: Wolfgang Stuppy) 

With a little help from their friends

Because orchid seeds lack a food reserve in the form of an endosperm or a large embryo, most of them, especially terrestrial ones, are generally unable to germinate on their own. They first have to engage in a mycorrhizal relationship with a fungus that helps to feed the emerging seedling. Some orchids are able to join up with many different species of fungi whilst others only accept a very specific fungus to enter their lives (or rather roots). Few orchids don’t need any fungus at all for their germination, such as certain species of Disa from South Africa, a remarkable exception among terrestrial orchids. 

Image of germinated seeds of Encyclia chloroleuca
Seedlings of the neotropical orchid Encyclia chloroleuca growing in a Petri dish. Placed on a nutrient medium under sterile conditions most epiphytic orchids can germinate without their fungal partner. (Photos: Suzie Wood) 

Why so many?

Their dependence on certain fungal partners is most probably the reason why orchids produce vast numbers of tiny seeds. With their small size, low weight and balloon-testa, orchid seeds are perfectly adapted to wind-dispersal. However, their strategy is not to travel long distances. Scattering large numbers of seeds with the wind merely heightens the chances that at least some end up in a place where they are lucky enough to meet their specific fungal partner without which they cannot germinate.

Long-distance dispersal would mean that the same amount of seed is distributed over a larger area which could actually lower the odds of encountering a compatible host in a suitable location. The fact that many orchid species are endemics with very limited distributions supports this theory. This does not mean, however, that their seeds are not able to cover long distances. Orchids managed to reach isolated islands far away from the mainland. As famously documented, they were among the first pioneers to resettle on the islets of Krakatoa after the catastrophic volcanic eruption of 27 August 1883. 

Images of open fruit and seeds of Asian tiger orchid
An open fruit of the Asian tiger orchid (Grammatophyllum speciosum) showing the placenta with some remaining seeds. Top right: close-up of the seeds (scale bar shows 1 mm; photos: Wolfgang Stuppy)

Why so small?

Shedding millions of seeds most of which go to waste, seems very wasteful. However, evolution shows no mercy with wasters and given the orchids’ success, their seed dispersal strategy must pay off. In fact, producing lots of very small seeds with literally no food reserve (apart from some oil droplets and starch grains in the embryo) is energetically inexpensive and doesn’t take up that much of a plant’s energy at all.

The survival benefits of producing millions of tiny seeds clearly outweigh the costs of producing them. Not only orchids prove this point. Other families, like the Orobanchaceae (broomrape family), pursue the same strategy. As parasites, they have a similar problem to orchids: they need to get their seeds to meet the right host partner in order to grow into a new plant. 

Photos of Ivy broomrape and seeds

Left: Ivy broomrape (Orobanche hederae, Orobanchaceae) growing outside the School of Horticulture at Kew Gardens. Right: just under 0.4 mm long, the tiny seeds of this parasite look similar to those of certain orchids but they lack the balloon-like seed coat (Photos: Wolfgang Stuppy) 

Vanilla ice cream and seed morphology

Since we are talking orchids here and most of us love ice cream, here’s a seed morphological nugget for you. Next time you treat yourself to some good quality vanilla ice cream you can discover that the tiny black spots in it are actually real vanilla seeds (in cheap ice cream they might be fake!). Vanilla is made from the fermented fruits (‘pods’) of the vanilla orchid (Vanilla planifolia). That’s how all those seeds end up in your ice cream. Sadly, though, the seeds of vanilla are nowhere near as exciting as those of other orchids. They are just very simple, unexciting looking, tiny black discs. Lacking the transparent balloon-like seed coat so typical of other orchids, their seeds are obviously not wind-dispersed.

In fact, the seed dispersal strategies of vanilla orchids are still enigmatic. The fruits of many Vanilla species, including the ones of V. planifolia, open when ripe to expose their tiny seeds covered in an extremely sticky layer of oil. The oil might serve as an adhesive to attach the seeds to visiting animals, which could either be insects or vertebrates. For example, it has been observed that euglossine bees are attracted by the fragrance of vanilla fruits and act as seed collectors and potential dispersers. 

Montage of Vanilla ice cream and vanilla seed

 Top: Vanilla ice cream (exciting!). Below: scanning electron micrograph of a vanilla seed (not very exciting!) (Photos: Wolfgang Stuppy) 

Orchid seed research at the Millennium Seed Bank

At this point I asked my colleague, Tim Marks, to tell us something about the research into orchid seeds he is involved in at the Millennium Seed Bank and he writes:

'Being wind-dispersed, orchid seeds are naturally dry at release and appear to be desiccation tolerant. The latter is essential for us to be able to preserve them under very dry and very cold (freezing!) conditions, as we do with other seeds in the Millennium Seed Bank.

'Unfortunately, orchid seeds have the reputation to be short-lived under seed banking conditions. Our research is engaged in finding out why this is and how we can extend their survival.

'A basic concept in understanding their specific requirements for storage is to test the relationship between temperature and moisture content upon viability and germination. By running long-term storage experiments with temperatures between -196°C (liquid nitrogen) and +20° (ambient), and a variety of moisture contents, it is possible to identify species-specific requirements.

'Some orchid species prove tolerant to a range of conditions, while others store better in liquid nitrogen. However, to prevent repeating this on all species, we are looking at a number of seed characteristics that could affect this response. One of these is lipid content of the seed, the physical properties of which could affect seed physiology as they go through the freeze and thaw cycles that stored seeds are subjected to. It is possible to produce thermal fingerprints describing the phase transitions between liquid and solid states that these go through, with the intention of developing a predictive model that will describe the observed responses to storage and during germination.' 

Photo of the cryo-storage facility at the Millennium Seed Bank
Our cryo-storage facility at the Millennium Seed Bank where we keep orchid seeds at -196°C (Photo: Wolfgang Stuppy)



Related Links

3 comments on 'Orchid seeds – Nature’s tiny treasures'

Orchids in the mist

By: Sarah Cody - 13 Nov 2013
Sarah Cody explores the valuable contribution that visiting researchers to the Millennium Seed Bank make to our understanding of seed behaviour, through the experiences of Ceci and Nelson, two visitors from Brazil who are helping us unravel the mysteries of orchid seeds.
  • Close

The joys of rural living

Having always worked in the city I have never made learning to drive a priority in my life. So, when I started at the Millennium Seed Bank last June, I was forced to rely on country buses to get into work every day. They are rickety and infrequent but on the plus side, the drivers are always very friendly and each morning I am greeted by the birds, rabbits, squirrels, deer and all the farmyard animals against the stunning backdrop of the Sussex countryside – feeling much like Julie Andrews in the Sound of Music, albeit on a bus. There are two others who make the journey with me every day: Nelson Barbosa Nachado-Netoand and Ceci Castilho Custódio, a Brazilian couple who took a sabbatical from their busy professorships and moved to the UK with their two children to carry out some of their own research, away from the demands of their students.

Photo of Nelson and Ceci

Nelson and Ceci on a misty morning in front of the UK Native Seed Hub, Wakehurst Place (Photo: Sarah Cody)

Seed collections in action

Being a world class organisation dedicated to conserving the seeds of wild plant species, the Millennium Seed Bank attracts many visiting researchers each year who draw on the knowledge, expertise and technological resources of the seed bank to further their own research objectives and, in so doing, contribute to a greater understanding of seed behaviour. The seeds of the 31,000 or so species that the Millennium Seed Bank Partnership has collected and banked so far are not just lying in a cold room collecting dust. Oh no - these seeds are destined for great things! The collections are being used to restore populations of threatened species in the wild, to provide options for the sustainable use of plants by communities, and for research.

Photo of seeds germinating

 Germination testing (Image: RBG Kew)

A project close to my heart is the Adapting Agriculture to Climate Change project which is involved in collecting seeds of the wild relatives of crop plants and making them available to breeders so that the useful traits they contain, such as disease resistance and high yield, can be bred into our crops, thereby improving agricultural efficiency and safeguarding our food security. To make sure these seeds live up to their great expectations, a crucially important part of the work done here at the seed bank is research into the viability of the seed collections, their germination and propagation. In other words, if these valuable seed collections are to remain useful for generations to come, we need to know what conditions the seeds need to stay viable long into the future and, when their moment of glory comes, we need to be able to grow them into living plants.

The commonest orchid in Britain

It wasn’t long before I discovered the reasons why Ceci and Nelson had left their tropical paradise to come and spend 8 months in the decidedly chillier South of England. Each morning, while walking down from the bus stop, Nelson would stop and check on these exquisitely beautiful wild orchids that lined the path to the Millennium Seed Bank building.

Photo of common spotted orchids

A wild population of Dactylorhiza fuchsii, the common spotted orchid (Photo: Nelson Neto) 

Their name is Dactylorhiza fuchsii or common spotted orchid - a white to purple-flecked terrestrial orchid which occurs throughout Europe and as far afield as Mongolia. As the commonest orchid in Britain, they are widespread, growing from alkaline marshes to chalk down-land, even gracing wasteland with their beauty. Like other orchids, the common spotted orchid produces tiny, dust-like seeds which rely on fungal relationships in order to germinate.   

Photos of Dactylorhiza fuchsii, the common spotted orchidPhotos of Dactylorhiza fuchsii, the common spotted orchid

A closer look at the common spotted orchid (Photo: Nelson Neto)

Ceci and Nelson's project

Supported by the Orchid Seed Science for Sustainable Use group, Ceci and Nelson, in their quest to unravel the mysteries of orchid seed behaviour, chose as their subject populations of common spotted orchid dotted throughout Wakehurst Place. Only a couple of flowers per inflorescence were pollinated, after which the rest of the flowers were pulled off. This was done so that the plant’s resources were maximally allocated towards seed production.  

Photo of the pollination of the common spotted orchid

Pollination of the common spotted orchid (Photo: Nelson Neto)

Within a few weeks, the flowers withered and a brown seed capsule developed. Ceci and Nelson then harvested the matured seeds, kept some in storage and brought some to the lab for their research. Their project currently focuses on how the oils present in orchid seeds influence the length of time they remain viable in cold storage. 

Photo of the seed capsules of Dactylorhiza fuchsii

Seed capsules of Dactylorhiza fuchsii (Photo: Nelson Neto)

There is a saying in Brazil...

Many a misty morning at the seed bank, Nelson and Ceci would say to me, 'Neblina baixa, sol que racha,' which is Portuguese and translates as, 'Low fog, sun that splits'. It means that if the day starts off foggy you can expect it to be so sunny and hot later on that the fruits of the castor bean plant (Ricinus communis) split open releasing their seeds. I didn't have any castor bean fruits on me to put their theory to the test, but this much I can say: A foggy morning always ended in a gloriously sunny day!

Ceci and Nelson leave the seed bank in December and I will miss them when they go. I hope our paths cross again.

- Sarah -


Related links


0 comments on 'Orchids in the mist'

Page  1  | 2 | 3 | 4 | 5 | 6 | 7  of 7  
Displaying 1 to 5 of 35 posts  

Follow Kew

Keep up to date with events and news from Kew

Sign up to Kew News

About us

Staff at the MSB

The Millennium Seed Bank Partnership works with over 80 countries worldwide as we work towards our current goal of collecting and storing seeds from 25% of the world's wild plant species. To complete such a target requires a wide range of skills and expertise including training, research, seed processing, database management and fundraising.

There are five teams based at Kew's Millennium Seed Bank at Wakehurst in West Sussex. You will hear from all of us at some point through this blog.

  • If you would like to publish material from this blog in a separate publication, please get in touch with Kew’s Press Office at See our full Terms & Conditions here.

Follow Kew on twitter

Sourced from @KewGardens

View this blog
See your favourite reasons to visit