26 August 1988
Vol 241, Issue 4869

About The Cover

Wild-type seedlings and one ethylene-insensitive mutant of Arabidopsis thaliana grown in an atmosphere containing the plant growth regulator ethylene. The wild-type seedlings show a growth habit characteristic for plants treated with ethylene: reduced elongation, thickened hypocotyls, and pronounced apical hooks. The ethylene-insensitive mutant elongated normally just as wild-type seedlings would do in an atmosphere without ethylene. Such a screen was used to select three ethylene-insensitive mutants among 75,000 seedlings grown in petri dishes. [See page 1086. Photo by Kurt Stepnitz, Instructional Media Center, Michigan State University, East Lansing, MI 48824]