The occurrence of patches or streaks of different coloured tissues in a plant organ, usually a leaf or petal. It may be due to infection, particularly viral infection, mineral deficiency, or physiological or genetic differences between the cells. The variegated petals of certain tulip varieties (e.g. Rembrandt tulips) are due to a virus infection. The variegated leaves of Coleus are caused by groups of cells developing different pigment combinations. This is a form of somatic variegation and heritable differences between different coloured parts of the leaf are not evident. In contrast the variegated leaves of, for example, Pelargonium are due to genetic variation arising from mutation (see periclinal chimaera). |
