[9] "Breaking" symptomology was first described in 1576 by Carolus Clusius, a Flemish professor of Botany at Leiden, who noted the variegation, or "rectification", so termed because it was believed that with the offset production of an entirely new "broken" bloom the plant was distilling, or rectifying, itself into a pure life form.

"[12] It was not known that the virus was responsible for this effect, so for centuries breeders believed that it was environmental conditions that attenuated the bulb and caused single colour tulips to break and streak.

[13] At the end of the eighteenth century, the notion that "breaking" in tulips was a manifestation of some kind of chronic disorder or weakness in the bulb was certainly considered among botanists; but it was still more or less believed that adverse environmental conditions were to blame.

Since the prime characteristics of the tobacco mosaic virus are that it damages the leaves and flowers of the plant, stunts growth, and lowers quantity and quality of the crop, it is puzzling to many academics and scientists that twenty more years passed before "breaking" was even suspected of being virus-induced.

Eventually, it was a series of bulb manipulation experiments begun in 1928 by Dorothy Cayley at the John Innes Horticultural Institution in Merton, South London, England that led to the discovery of the virus.

The genetic code of TBV has now been sequenced and the virus is recognized as a member of the genus Potyvirus (family Potyviridae).

[1] In certain varieties STBV causes full breaking or light breaking, when due to a lack of anthocyanin, pigment present in the surface chromoplast cells fades and the lighter color (white or yellow) of the internal mesophyll is exposed, appearing as irregular streaks or fine featherings.

Its distribution is world-wide and had been reported in all temperate regions where tulips are grown; it is particularly common in southern Europe where the aphid vectors are abundant early in the growing season.

Virus transmission by aphids causes millions of dollars of damage in the flower bulb sector annually.

Apparently, the first aphids of the season had already contributed, in great extent, to the virus transmission, which was observed locally in the tulip plots.

These results should enable formulation of crop protection guidelines that are fine-tuned with the risk of virus transmission, which will help decrease environmental damage caused by pesticides.

[26] Modern tulip varieties infected with the virus are fragile, and are usually much smaller than normal healthy blooms, with a reduced stem length.

There are only a few varieties of older, truly "broken" tulips still in existence such as Zomerschoon, but only because the worst aspects of the virus have somehow remained benign.

One such example is the rare Absalon, which dates from 1780; a "bizarre" colored variety, it displays gold flames against a dark chocolate brown background.