When is a mushroom not a mushroom? When it is a Maltese mushroom, of course!

Photo by Hans Hillewaert licensed under CC BY-ND 2.0.

Meet Cynomorium coccineum aka the Maltese mushroom. Despite the common name and overall appearance, this is not a fungus. It is indeed a plant. Cynomorium coccineum is a holoparasite. It produces no chlorophyl of its own and relies solely on a host plant for all of its water and nutrient needs. It is said to parasitize the roots of halophytes or salt-loving plants and thus, is most commonly found growing in salt marshes in addition to dry, sandy habitats in coastal areas.

Native to the Mediterranian region and extending into parts of Afghanistan, Saudi Arabia, Iran, and Central Asia, this species is really only ever found during the rainy season. Most of its life is spent underground, emerging only to display its flowers. Only when enough energy has been garnished from the host will this plant throw up these strange flower spikes. As you can tell from the picture, the spikes are jam packed with highly reduced flowers. The flowers give off a scent that has been likened to cabbage. It is thought that flies take up the bulk of the pollination of these blooms.

Photo by Alastair Rae licensed under CC BY-ND 2.0.

Photo by Hans Hillewaert licensed under CC BY-ND 2.0.

As you can probably guess by its strange appearance, the taxonomic affinity of this strange parasite has been the subject of much debate. For a long time, many botanists placed it in the family Balanophoraceae but more recent genetic work suggests it belongs in its own family, Cynomoriaceae. It is the only genus within that family but interestingly enough, Cynomoriaceae is located within the order Saxifragales, somewhere near Crassulaceae, making it a distant relative of stonecrops like sedum. No matter where its located on the tree of life, Cynomorium coccineum is surely one of the strangest plants on Earth.

Photo Credits: [1] [2]

Further Reading: [1] [2]

Meet the Fire Lily

Photo by Callan Cohen licensed under CC BY-SA 3.0

The flora of the South African fynbos region is no stranger to fire. Many species have adapted to cope with and even rely on fire to complete their lifecycles. There is one species, however, that takes this to the extreme. It is a tiny member of the Amaryllidaceae aptly named the fire lily (Cyrtanthus ventricosus).

The fire lily is not a big plant by any means. Mature individuals can top out around 9 inches (250 mm) and for most of the year consist of a nothing more than a small cluster of narrow, linear leaves. As the dry months of summer approach, the leaves senesce and the plant more or less disappears until its time to flower. However, unlike other plants in this region that flower more regularly, the fire lily lies in wait for a very specific flowering cue - smoke.

It has been noted that fire lilies only seem to want to reproduce after a fire. No other environmental factor seems to trigger flowering. This has made them quite frustrating for bulb aficionados. Only after a fire burns over the landscape will a scape emerge topped with anywhere from 1 to 12 tubular red flowers.

This dependence on fire for flowering has garnered the attention of a few botanists concerned with conservation of pyrophytic geophytes. Obviously if we care about conserving species like the fire lily, it is extremely important that we understand their reproductive ecology. The question of fire lily blooming is one of triggers. What part of the burning process triggers these plants to bloom?

By experimenting with various burn and smoke treatments, researchers were able to deduce that it wasn’t heat that triggered flowering but rather something in the smoke itself. Though researchers were not able to isolate the exact chemical(s) responsible, at least we now know that fire lilies can be coaxed into flowering using smoke alone. This is a real boon to growers and conservationists alike.

Photo by Callan Cohen licensed under CC BY-SA 3.0

Seeing a population of fire lilies in full bloom must be an incredible sight. Within only a few days of a fire, huge patches of bright red flowers decorate the charred landscape. They are borne on hollow stalks which provide lots of structural integrity while being cheap to produce. The flowers themselves are not scented but they do produce a fair amount of nectar. The bright red inflorescence mainly attracts the Table Mountain pride butterfly as well as sunbirds.

Once flowering is complete, seeds are produced and the plants return to their dormant bulbous state until winter when leaves emerge again. Flowering will not happen again until fire returns to clear the landscape. This strategy may seem inefficient on the part of the plant. Why not attempt to reproduce every year? The answer is competition. By waiting for fire, this tiny plant is able to make a big impact despite being so small. It would be impossible to miss their enticing floral display when all other vegetation has been burned away.

Photo Credits: [1] [2] [3]

Further Reading: [1] [2] [3]

The Giant Genomes of Geophytes

Canopy plant (Paris japonica) Photo by Radek Szuban licensed under CC BY-NC 2.0

A geophyte is any plant with a short, seasonal lifestyle and some form of underground storage organ ( bulb, tuber, thick rhizome, etc.). Plants hailing from a variety of families fall into this category. However, they share more than just a similar life history. A disproportionate amount of geophytic plants also possess massive genomes. 

As we have discussed in previous posts, life isn't easy for geophytes. Cold temperatures, a short growing season, and plenty of hungry herbivores represent countless hurdles that must be overcome. That is why many geophytes opt for rapid growth as soon as conditions are right. However, they don't do this via rapid cell division. 

Dutchman's breeches (Dicentra cucullaria) emerging with preformed buds.

Instead, geophytes spend the "dormant" months pre-growing all of their organs. What's more, the cells that make up their leaves and flowers are generally much larger than cells found in non-geophytes. This is where that large genome comes into plant. If they had to wait until the first few weeks of spring to start their development, a large genome would only get in the way. Their dormant season growth means that these plants don't have to worry about streamlining the process of cellular division. They can take their time. 

As such, an accumulation of genetic material isn't detrimental. Instead, it may actually be quite beneficial for geophytes. Associated with large genomes are things like larger stomata, which helps these plants better regulate their water needs. The large genomes may very well be the reason that many geophytic plants are so good at taking advantage of such ephemeral growing conditions. 

When the right conditions present themselves, geophytes don't waste time. Pre-formed organs like leaves and flowers simply have to fill with water instead of having to wait for tissues to divide and differentiate. Water is plentiful during the spring so geophytes can rely on turgor pressure within their large cells for stability rather than investing in thick cell walls. That is why so many spring blooming plants feel so fleshy to the touch. 

Taken together, we can see how large genomes and a unique growth strategy have allowed these plants to exploit seasonally available habitats. It is worth noting, however, that this is far from the complete picture. With such a wide variety of plant species adopting a geophytic lifestyle, we still have a lot to learn about the secret lives of these plants.

Photo Credits: [1] [2]

Further Reading: [1]