Green-striped Trilliums

While working with the Shepherd fifth graders at Audubon Woods Preserve earlier this week I noticed dozens of Large-Flowered Trillium blooms.  Most of these were the standard white variety.

But, there were a few flowers with a green stripe down the center of each white petal.

The green stripe is a sign of mycoplasma infection

These flowers have been infected by something called a mycoplasma.  A mycoplasma is a form of bacteria that lacks a cell wall.  This infection will first be noted as a green stripe near the center of each petal.  As the infection spreads in successive years the stripe widens until the whole petal may be green.  This infection can also cause deformed petals or even double blooms (so each flower would have six instead of three petals).  This infection eventually impairs the reproductive ability of the infected plant and prevents successful seed production.

This Trillium bloom is almost entirely green and its leaves also show signs of infection.

A mycoplasma infected Trillium