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Horticulture Group Newsletter March 2014

tomato slice

4 Mar 2014

Our first event for 2014 was the Professional Horticulture Group South West Conference held at Bridgwater College, Cannington on 12 February entitled 'Managing Green Space in a Time of Austerity'. Three excellent speakers had been assembled for this meeting and a brief report of their talks appears below.

Congratulations to Prof Geoff Dixon who has been made an Honorary Member of the International Society for Horticultural Research, one of only five UK members to be so honoured.

This month we may not be following the now established pattern of a Plant of the Month and a Medicinal Plant of the Month. Inspired (?) by the recent inundations, we have picked a terrestrial plant of the month and an aquatic plant of the month (with a twist….)

Editor

Managing Green Space in a Time of Austerity

The Cannington Conference held each February has now become a welcome fixture in the Professional Horticultural Growers South West (PHGSW) calendar. This year Prof Geoff Dixon had assembled three speakers to answer the challenge of 'Managing Green Space in a Time of Austerity'. The speakers were;

Nick Wray, Curator of the Bristol University Botanic Garden who has had the additional challenge of moving the garden to a new site. (see also Newsletter July 2011)

Iain Park, Director of Grounds at Exeter University who has to manage a university campus where building work is a regular feature of the landscape.

Chris Evans, Nursery manager at Bournemouth Parks who, after a career spanning art and design, the Royal Navy (including service in the Falklands) and a period as a computer programmer, finally retrained in horticulture.

Although all three had very different remits to fulfil a common theme emerged - the importance of selling - ensuring that the decision makers in the respective university or council appreciated the value of green space to the organisation. In Nick Wray's case his initial challenge was to ensure that the university felt the need for a Botanic Garden at all. This entailed not just convincing them of the need but also defining quite clearly its purpose and focus.

Exeter University photo by Derek Harper Exeter University (picture right) has for many years prided itself on the horticultural quality of its campus so Iain Park's challenge has been to ensure that this is enshrined in the university's policy and has become a 'selling point' in attracting both staff and students.

All three had met this aim by first and foremost providing good horticulture to argue with and then fostering relations with the managers above. In each case this argument was backed up by ensuring the profile of the horticulture was regularly publicised in ways that the managers could appreciate.

Equally important to convincing the paymasters is generating a sense of the gardens belonging to the town and its people. Chris Evans has used his art and design background to design award-winning displays at Chelsea, Hampton Court and Tatton Garden shows. These not only act as great publicity for the town but also a much appreciated photo opportunity for the administrators to be pictured with the trophy as well as something the townspeople can be proud of.

ballast seed project - photo by Bristol University While Nick Wray's approach is similar he utilises the groups, particularly overseas groups, that visit the garden in the same way. In addition he has an active outreach programme to foster links between the Garden and the City. An excellent example is the Garden's Ballast Seed Project. This is built around the many plants that now grow around the Bristol dock area and beyond which arrived from overseas in the ballast brought in the holds of the many sailing ships entering the port in times past. As well as planting these within the botanic garden they have also taken this into the city on a floating barge.

Iain Park has to be more subtle in his approach although university administrators do appreciate being able to greet visitors who have already been softened by the pleasant gardens they pass to reach the buildings. A particular problem he faces is the appearance of building sites within the campus. In addition to forward planning to mitigate the impact of such development, he has also created a 'Mitigation Squad' to immediately rectify any damage that may occur while the contractors and authorities argue fault and liability.

The result in all three examples is gardens that have the full support of their respective authorities as well as being appreciated by the townspeople.

Terrestrial Plant of the Month

Musa acuminata (AAA group) 'Gros Michel'

Cavendish Bananas photo by Arpingstone Chances are, you have never eaten a good banana. The banana that occupies the shelves of European and American grocery stores is an inferior replacement for its predecessor. Here's the story:

In the late 19th century, a few entrepreneurs began to export bananas from the tropics to the United States and Europe. Though an astounding number of banana varieties exist in the world, the export industry centred on one cultivar: Gros Michel. Very few of the world's banana varieties are hardy and consistent enough to withstand the rigours of international shipping; the Gros Michel had the necessary characteristics, and furthermore, it was delicious.

Soon after bananas caught on in the United States and Europe, a mysterious malady began to devastate plantations in Panama. Dubbed Panama disease or mal de Panamá in Spanish, the pathology was caused by the fungus Fusarium oxysporum f.sp. cubense. It was virulent and relentless; for the entire first half of the 20th century, producers played a cat-and-mouse game with the fungus, and the cat won.

As a desperate last-minute solution, growers switched from the Gros Michel to the only trade-ready variety known to be resistant to Panama disease: the Cavendish (pictured). Though the resistance of Cavendish was common knowledge in the banana world, producers were reluctant to switch to this banana due to its relative lack of flavour. By 1960, substitution was complete, and to this day, we are still eating the bland Cavendish.

Though commercial production of the Gros Michel was wiped out, the banana is not extinct. It is still grown for small-scale local consumption in parts of the tropical world. Supported by a Wallace Watson Award from St Catherine's College, Oxford, I undertook a five-week expedition to Costa Rica and Panama to learn about bananas, work with banana researchers and farmers, locate a disease-free Gros Michel plant, and send a cutting back to England to be planted ultimately in the display collections at Oxford Botanic Garden.

I acquired the plant from the germplasm bank of an agronomy institution called CATIE (Centro Agronómico Tropical de Investigación y Enseñanza) in Turrialba, Costa Rica. It is the product of in vitro meristem propagation, a method that ensures disease-free plant tissue. The material from which it was propagated was collected from farmers in the mountainous Turrialba area, where locals still eat Gros Michel bananas regularly. They grow Cavendish bananas primarily to feed pigs.

It's hoped that the exhibition of this plant will educate visitors about an event that nearly wiped out the world's favourite fruit, unbeknownst to most of its consumers; perhaps it will also inspire them to give more thought to the food they eat. For most residents of developed countries, food seems to simply appear in grocery stores, conveniently packaged and reliable.

There is more at stake, though, than the relation of an interesting narrative. A new strain of Panama disease has appeared recently in Asia, and not even the Cavendish is resistant this time. However, awareness of the impending threat and funding for initiatives against it are both startlingly scant.

The banana is the world's fourth most important staple crop, behind wheat, rice, and maize. A banana crisis could have catastrophic implications for the economic and nutritional security of millions worldwide. If history repeats itself, it is likely to do so with more force than in the first epidemic. Awareness is an important prophylactic.

Appreciate your bananas, not only because of work that goes into getting them across the ocean, but also because they may not be around forever.

Myles Karp, (MSc Cognitive and Evolutionary Anthropology) St Catherine's College, Oxford University

Aquatic Plant of the Month

Villarsia capensis, Menyanthaceae, Cape Bogbean

Bowiea volubilis photo by Citron March is the time of year when many gardeners and horticulturists are obtaining seeds ready for the new growing season ahead. Botanic Gardens generate seed lists (Index Seminum) each year, and distribute these to other institutions across the world. From these, Botanic Gardens can request seed each winter and at this time of year it's a bit like Christmas as seed packets arrive each day. This is a good way of increasing and diversifying your collection, but sometimes you get an unexpected surprise.

A few years ago, seed of the plant Bowiea volubilis (pictured ) was requested from a particular Index Seminum. This interesting plant in the Hyacinthaceae (now Asparagaceae) is a bulbous, succulent, scrambling plant from the deserts of South Africa.

The seeds arrived, were sown, and germinated very successfully. They were grown on, planted out in specialist xerophyte compost and nurtured by the glasshouse horticultural team. One day, the team were asked to plant the plants out into the arid house as they were flowering and of sufficient size for display. A chance remark by one of the horticultural team, 'They're very thirsty for arid house plants' led to the team looking at the flowering plants more closely.

Villasia capensis cape bogbean photo by Andrew Massyn Now when you are looking after a collection of over 5000 different taxa, you can be forgiven for not knowing exactly what each plant should look like, especially when you consider there are in the region of 350,000 different species of flowering plants out there.

On closer inspection, the flowers (pictured right) clearly belonged to a typical 'dicot' rather than a typical 'monocot' - there were five petals rather than three, the leaves had reticulate veins rather than parallel veins and so on.

The next stage was to 'key' out the plant, but this did not result in a new identity - mainly as we discovered later because we were answering the key question incorrectly. The crucial piece of information we had wrong? This was an aquatic plant, not a terrestrial one! What we actually had was Villarsia capensis, an aquatic plant from South Africa, rather than Bowiea volubilis, a succulent from South Africa (pictured right).

Villarsia capensis bush photo by Andrew Massyn It's a testament to the individual care that the plants received in the nursery house that these aquatic plants managed to survive and thrive in very free draining compost! The story had a happy ending anyway after the adventure along the way - the plants were displayed in a marginal position in the Lily House pond in the Botanic Garden glasshouses.

Alison Foster
Oxford Botanic Garden

Horticulture Industry News

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We've all been taught that DNA is the physical foundation of heredity. The fact that the functioning of our genes is also affected by epigenetic marks has been known for decades. What is now clear is that in plants these non-genetic characters can be inherited through many generations. More

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In a field experiment, intercropping reduced the reproductive efficiency of the leafhopper. Nabis was more effective at reducing leafhopper abundance, and protecting alfalfa from hopper-burn, in the polyculture than in the monoculture of alfalfa. The orchardgrass, a nonhost for leafhoppers, increased leafhopper movement, and Nabis captured leafhoppers more efficiently when the herbivores were more mobile. More

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The BBSRC SUREROOT project builds on earlier BBSRC-funded research where it was reported that a forage grass hybrid known as Festulolium and designed originally for livestock agriculture, also held a hidden underground and previously unknown property. The large well developed root systems of Festulolium combat flooding, reduce soil erosion and compaction and offer opportunities for significant carbon capture and storage at depth in soils.

Their grass root-soil interactions instigated a change in soil structure leading to increased water retention with a prolonged and significant 51% reduction in rainfall run-off compared with equivalent grasses that were grown alongside and that are currently used extensively throughout the UK. More

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Nitric oxide gas is one such signal. In plants, NO regulates many different processes throughout the plant's lifetime from seeds to flowering and responses to the environment. Although the effect of NO on plants has been known for many years, a general mechanism for the initial sensing of this important molecule has remained elusive. We have identified a small number of key proteins, called transcription factors, which act as 'master sensors' to control NO responses throughout the plant life cycle.

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Events Calendar

SCI Horticulture Group events are listed here

Other Events of Interest

Precision Irrigation Conference
6 Mar, UK Irrigation Association
Peterborough, UK

Vegetable Grafting
17 - 19 Mar, International Society for Horticultural Science
Wuhan, China

From Concept to Exit - 'Good Business Planning'
19 Mar, InCrops
Harpenden, UK

New Ag International
26 - 28 Mar, New Ag International
Warsaw, Poland

Physiological Principles and Their Application to Fruit Production
26 - 28 Mar
Geneva, USA

UK PlantSci 2014
31 Mar - 1 Apr, UK Plant Science Federation
York, UK

Pollinators in Agriculture
1 - 3 Apr, Association of Applied Biologists
Brussels, Belgium

The Genus Lilium
1 - 3 Apr, International Society for Horticultural Science
Zhangzhou, China

Trees, People and the Built Environment
2 - 3 Apr, Chartered Institute of Foresters
Birmingham, UK

Global Berry Congress
7 - 9 Apr, Eurofruit
Amsterdam, The Netherlands

Wild Relatives of Subtropical and Temperate Fruit and Nut Crops
7 - 12 Apr, Wild Relatives of Subtropical and Temperate Fruit and Nut Crops
Baku, Azerbaijan

Investment for business growth - the legal side explained
11 Apr, InCrops
Harpenden, UK

Natural & Organic Products Europe
13 - 14 Apr, Diversified Communication
London, UK

Sulfur Metabolism in Plants
14 Apr, Institut für Forstwissenschaften
Freiburg, Germany

Advances in Cider Technology
16 Apr, Association of Applied Biologists
Pershore, UK

Plant Genomics Conference
12 - 13 May, Global Engage
London, UK

Brassica Conference
15 May, UK Brassica Research Community
Wellesbourne, UK

Loquat Symposium
12 - 15 May, International Society for Horticultural Science
Palermo, Italy

Society of Biology AGM
15 May
London, UK

Plant Chemical Biology
16 May, Agrinet
Jealotts Hill, UK

If you would like to advertise a forthcoming event please contact. ester.monfort@soci.org

Horticulture Group Contact Details

For submitting ideas or to volunteer to be part of a committee or a group, please contact:

Chairman - Peter Grimbly
Meetings Secretary - Alison Foster
Minutes Secretary - Margaret Waddy
Newsletter co-ordinator - Sue Grimbly scihortigroup@btinternet.com
Group Contact - Ester Monfort Martinez, E: ester.monfort@soci.org T: +44(0)20 7598 1584

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