Key Code: C1

Symptoms noted are evident on the underleaf surface and involve discoloration or damage to tissue:

Key Code: c1a

Rust colored tissue may result from drying of tissue as a result of the application of soap or oil type pesticides.

Key Code: c1b

Rust colored lower leaf surface may be in reaction to low fertility becoming evident sooner than chlorosis of upper tissue.

Key Code: c1c

Environmental stress, particularly constant air flow, may result in small, wing-like leaves that originate along veins called enations. Most likely to occur on plants located near sources of constant air movement along fan walls, near doors or vents, etc. where leaves are continually subject to air flow. Protect plants from the exposure to help minimize the development of enations.

Key Code: C2

Symptoms of abnormality are expressed in the rate or timing of bract color development. No other serious problems are noted. Delayed color may be the result of:

Key Code: c2a

low light intensities

Key Code: c2b

low greenhouse temperatures (below 68º F average) during finishing may result in slow development and reduced bract size.

Key Code: c2c

night lights entering the greenhouse preventing normal flowering.

Key Code: c2d

heat delay from high night temperatures (72º F+) in September and October.

Key Code: c2e

application of plant growth regulators in excessive quantities or too late for the specific chemical and method of application.