Application of 0.75 Ibs per acre ethephon to bell peppers (variety Keystone Resistant Giant) when 10% of the fruit were red or in the breaker stage resulted in highly significant increases in yield of red fruit at harvest 22 days after treatment. Ethephon treated plants produced almost twice as much red fruit as the untreated check. In a subsequent experiment, ethephon treatment at 40% field maturity resulted in no significant change from the untreated check. Results indicate fields should be treated early to obtain maximum ripening response. A concentrated fruit set with a majority of mature green fruit should give the best response. No detrimental effects on foliage or fruit quality were observed.

W. L. Sims, Extension Vegetable Specialist, and Keith Trammell of Rogers Brothers Co. reviewed the manuscript.