Tag Archive | orchid fungi

The Proper Relationship Between Orchids and Fungus

The orchid relies on its’ relationships with other organisms to assist in the overall health of the plant. One of these is fungi. They rely on them to assist in the germination of seeds and can form a partnership for the whole life of the plant.

The ones which grow on trees form a relationship not only with the host, but with the fungus they are reliant on. It makes you wonder what the implications would be for the plant if it didn’t form this marriage.

Where Does This Fungus Exist?

The fungus lives inside the root cells of the plant and this marriage of orchid and fungi results in a dual organism known as mycorrhiza. The roots provide an ideal growing environment for the fungus, as it is devoid of competition and it is thought that the flower provides the fungus with vitamins.

Parts of this fungi penetrate the root wall and has contact with the soil, which is rich in nutrients such as cellulose and other carbon compounds. This mixture is then broken down by many microbial guests into a soluble form which can be used by the flower.

How It Affects The Growth of Your Flowers

The millions of dust-like tiny seeds can begin to germinate without the presence of this specific fungus. However, the process is only complete once it has infected the embryo. The marriage between these plants and fungi is necessary at this point because the plant is unable to absorb nutrients from the soil and the tiny seed does not have any food reserves to sustain growth.

Once the flower matures, there is still a reliance on the fungi to maintain the partnership, as some species lack chlorophyll, so the dependency on each other can last throughout the lifetime of the plant.

The Phantom Orchid

One specific plant found in North America, in only four states in the United States and in the south western area of British Columbia, Canada, is called the Cephalanthera austiniae or Phantom. It’s found mainly in old growth forests and is known to associate with one fungal family only.

They form associations with several species of trees, but it is not presently known which species are connected to this particular tree partnership.

This flower is a totally white orchid and even though it has a flowering stem, it primarily lives below ground and only sends the flowering stems above ground when the conditions are suitable. The plant produces a low number of flowers which may occur primarily because of the climatic and pollinator limitations. If the growing conditions are severe then the species may be able to survive in a dormant state until the conditions improve.

In British Columbia, the Phantom plant occurs mainly in a coniferous forest, but it has also been found in forests dominated by the big leaf Maple Trees. This species has shown a tendency to live in sites with little or no competition.

Things To Keep In Mind When Cultivating These Plants

Recent studies have shown that even though some forest cover might be variable, there seems to be a preference for limestone sites. It has even been found adjacent to a limestone quarry in British Columbia, on heavily limed compost heaps and old shell middens. However some populations have no apparent association with limestone.

The partnership between the orchid fungus can last a lifetime, and divorce can be lethal to these plants. Scientists have tried to imitate the relationship between the two, without success, which is a reason why so many species are now endangered. No-one has been able to replicate this wonderful partnership and if the fungi should die during experimentation, no amount of watering or fertilizing could save a dependent flower.