Ethylene Production by Albedo Tissue of Satsuma Mandarin (Citrus unshiu Marc.) Fruit

Abstract

Isolated albedo tissue of Satsuma mandarin (C. unshiu Marcovitch ev. Owari) fruit produced a large quantity of ethylene during incubation at 26.degree. C in the dark. When sliced, albedo tissue began producing ethylene at an increasing rate until a maximum was reached after incubation for about 30 h. Aged albedo discs which were capable of producing ethylene actively converted L-[U-14C]methionine into ethylene and CO2. In fresh tissue almost no measurable conversion of radioactive methionine into ethylene took place. Conversion of labeled L-methionine into ethylene was totally inhibited by the addition of nonradioactive L-methionine or L-ethionine. It appears possible that methionine is a precursor of ethylene in the aged albedo discs. Ethylene synthesis in the aged albedo tissue was markedly reduced in the presence of cycloheximide, suggesting that there may be a rapid turnover of the ethylene-producing system and that its formation involves protein synthesis. Actinomycin D exerted no effect.