Ancymidol drenches, reversed greenhouse temperatures, postgreenhouse cold storage, and hormone sprays affect postharvest leaf chlorosis in Easter lily

The interactions of ancymidol drenches, postgreenhouse cold storage, and ho rmone sprays on postharvest leaf chlorosis and flower Longevity of 'Nellie White' Easter lilies (Lilium longiflorum Thunb,) were investigated, Ancymid ol drenches (0.5 mg/plant twice) during early growth resulted in leaf chlor osis In the greenhouse which intensified further during postharvest, Cold s torage (4 degrees C) of puffy bud stage plants for 2 weeks also accelerated leaf chlorosis, The combination of ancymidol treatment with cold storage r esulted in the most severe leaf chlorosis, Promalin (GA(4+7) and BA each at 100 mg.L-1) sprays completely prevented postharvest leaf chlorosis, wherea s ProGibb (GA(3) at 1000 mg.L-1) was ineffective. Cold storage reduced flow er longevity and increased bad abortion, however, the degree of bud abortio n varied among experiments in different years. Both ProGibb and Promalin sp rays increased flower longevity. Compared to positive DIF (difference betwe en day and night temperature) grown plants, forcing under negative DIF (-8 degrees C) increased the severity of postharvest leaf chlorosis, Leaves wer e sampled from basal, middle, and upper sections of the stem after 4 and 12 days in a postharvest evaluation room, and analyzed for soluble carbohydra tes and N, Total leaf soluble carbohydrates and N concentrations were less in basal and middle sections of negative DIF-grown plants than in positive DIF-grown plants. Leaf chlorosis was associated with depletion of soluble c arbohydrates and N in the leaves. Chemical names used: alpha-cyclopropyl-al pha-(p-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); gibberellic acid (G A(3),); gibberellins A(4)A(7) (GA(4+7)); N-(phenylmethyl)-1H-purine 6-amine (benzyladenine).