By Nathan Smith
Think of a word to describe disease. Any number of negative adjectives may come to mind: painful, sorrowful, terrifying. But can a disease be beautiful? Enter Tulip Breaking Virus (TBV), a disease of (unsurprisingly) tulips that causes colour-breaking in the plant’s flower. Colour-breaking is where the flower of the tulip displays more than one colour; for tulips, in a world free from disease, come only in solid colours.
In fact, TBV is one of five plant viruses that cause tulips to break this restriction, creating patterned petals in infinite combinations of streaks, stripes, feathers and flames. The cause of such wondrous symptoms is the irregular distribution of anthocyanin within the plant cells. Within TBV two strains are recognised, a severe and a moderate form. The severe form causes lack of anthocyanin leading to light breaking and the moderate form causing dark breaking due to excess anthocyanin.
The virus is historically important as being the cause of tulip mania, a period in Dutch history where tulip bulbs sold for increasingly high amounts. It was the rare bulbs affected by TBV that sold for the most, and at one point 12 acres of land were offered for one bulb of Semper Augustus, believed to be one of only two bulbs in existence at the time!
Infected tulips display other, less aesthetically pleasing symptoms too. Leaves become mottled and the bulb becomes increasingly stunted until it lacks the energy to flower and the bulb withers away or breaks apart. The unique beauty of these flowers is temporary, and after a brief flash of radiance their delicate splendour is lost to the annals of history. This is true for some of the most famous varieties, such as Semper Augustus or Viceroy, of which a single bulb sold for more than ten times the average craftsman’s annual earnings during the tulip mania.
Today, infected tulips still exist such as Absalon, which flowers a chocolate background with rich yellow swirls and has existed since at least 1780. However, to prevent spread of the virus many countries, including the UK, have placed a ban on the sale of “broken bulbs”. For those still desperate to get their hands on patterned tulips, stable variants do exist that are the result of breeding and not of viral infection, such as Rem’s Sensation, though to many they do not match the spellbinding beauty of a flower doomed to die.