Faris Banding in Panicoid Grasses

Abstract

Transverse chlorotic lesions (Faris bands) develop on the leaves of some panicoid grasses after exposure to low night temperatures. Generally, the higher the day temperature and the lower the night temperature, the greater the number and intensity of the bands which are formed. Most plants, when maintained continuously under conditions which initially produced bands, ceased producing them after only a few days, which suggests that some adaptation process occurs.

Amongst the panicoid grasses there was a wide between-plant, between-species and between-genus variation in banding sensitivity; plants which produced fewest bands or required the lowest temperatures to produce bands frequently showed better growth at low temperatures. However, as there are some wide departures from this general rule, banding sensitivity would appear to be a poor selection criterion for low-temperature hardiness.