1.  Virus
Leaves are mottled with yellow blotches. Or they have yellow streaks or flecks that later turn dark brown or black. Leaves may have partial, complete, or concentric rings of dark-colored tissue. New leaves may be stunted and cupped. Flowers may be mottled and the colors broken. They may be moderately or severely distorted, and may have brown flecks or streaks in them. Affected flowers do not last long.