from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun The state or process of becoming green, especially the abnormal development of green coloration in plant parts, such as flowers, that are normally not green.
from The Century Dictionary.
- noun Greenness; viridescence.
- noun In botany, the abnormal assumption of a green color by organs normally bright-colored, as when the petals of a flower retain their characteristic form, but become green.
from the GNU version of the Collaborative International Dictionary of English.
- (Bot.) The act or state of becoming green through the formation of chlorophyll.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun biology The
abnormaldevelopment of green pigmentationin plantsnormally not green, like flowers and shoots. Symptom may be characteristic of phytoplasmainfection in plants.
Sorry, no etymologies found.
= -- The petals also are frequently replaced by leaves, though in many of the recorded instances the change has been one of colour only; these latter are strictly cases of virescence.
Many of the cases recorded as reversions of the parts of the flower to leaves are simply instances of virescence; indeed, it is not in all cases easy to distinguish between the two states.
Frondescence of the petals has been observed most frequently in the following cases; some, perhaps, were cases merely of virescence, q. v.; see also under Chloranthy, Prolification.
Owing to the vagueness with which the word has been applied by various authors, it becomes very difficult to ascertain whether the recorded instances of chloranthy were really illustrations of what is here meant by that term, or whether they were cases of mere virescence (green colour, without other perceptible change), or of prolification (formation of adventitious buds).
Some flowers are more liable to virescence than others.
Some of the above are probably cases of mere virescence rather than of phyllody.
Indeed, virescence or chloranthy is very intimately connected with this aberration, as might have been anticipated, for if the parts of the flower assume more or less of the condition of stem-leaves or bracts, it is quite natural to expect that they will partake likewise of the attributes of leaves, even at the expense of their own peculiar functions.
= -- This change, spoken of by most authors as retrograde metamorphosis of the petals into sepals, or as a substitution of sepals for petals, is obviously a condition that is in most cases hardly distinguishable from virescence of the corolla, or from multiplication of the sepals.
It must be distinguished from virescence, or the mere green colour of the floral organs, and from chloranthy, in which all or the greater portion of the parts of the flower are replaced by leaves.
Gesneriana_, the change in question being generally attended by a partial virescence.