It’s always been my understanding that orchids are not parasites. However, I came across an article this morning that declares (among other things) just the opposite. I thought it was interesting enough to share:
Petals with a purpose from The Star Online, Malaysia:
…For all their diversity, orchids share one common trait: they rely solely on other organisms, particularly fungi, to survive – a characteristic which Jutta says is quite distinctive and serves as a source of confusion to scientists.
“Fungi play a crucial role in the biology of many plants because they convert oxygen to compounds that plants can use to grow, but orchids depend on fungi well into maturity.” Beneath their good looks, orchids are parasites, says Jutta. “This conclusion was established only at the beginning of the last century, and after much debate, it has finally been accepted and scientifically proven.
“Orchids use fungi as a means of nutrient transport. The plant even produces sugary matter for the fungi, which feed on carbohydrates, to attract them.”
Once the fungus penetrates a certain point within the plant’s cells, says Jutta, the cells will secrete an enzyme that breaks down the fungal tissues, keeping the fungus in check and preventing it from invading the plant further.
The dissolved fungal tissue is then broken down into vitamins, fatty acids and carbohydrates which the plant uses for its own growth.
“This cycle is repeated over and over, and each cell is re-colonised several times.” This process, she adds, begins as soon as an orchid seed germinates.
“When a seed’s outer shell is broken, it is ‘invaded’ by a fungus, but the seed contains the enzyme that keeps it in check, not allowing the fungus to destroy it.”
Once this happens, the fungus is not killedbut it simply becomes a vessel through which the orchid derives nutrients for its own development, says Jutta.
But while orchids are not prized for their parasitic characteristics, they are certainly appreciated for their incredible beauty.