Lc. Cushman et al., CULTIVAR, FLOWER STAGE, SILVER THIOSULFATE, AND BA INTERACTIONS AFFECT PERFORMANCE OF POTTED MINIATURE ROSES, HortScience, 29(7), 1994, pp. 805-808
Experiments were conducted to study the interaction of cultivar, flowe
r stage, silver thiosulfate (STS), and BA on flower senescence and lea
f abscission in greenhouse grown potted miniature roses. plants of Ros
a L. 'Meijikatar' (Orange Sunblaze) and 'Meirutral' (Red Sunblaze) wer
e sprayed with several concentrations of STS and BA in factorial combi
nation. In winter, plants were sprayed with STS at 0 or 2 mM and BA at
0, 0.02, 0.04, 0.11, 0.22, or 0.44 mM. In spring, flowers at three st
ages of development were sprayed with STS at 0, 2, or 3 mM, and BA at
0, 0.02, 0.04, 0.22, or 0.44 mM. One day after treatment in both exper
iments, plants were placed in darkness at 16C for 4 days to simulate s
hipping, and then they were evaluated in a controlled environment at 2
1C. Poststorage floral longevity (PSFL) was longer far 'Meirutral' tha
n for 'Meijikatar' plants, regardless of chemical treatment or flower
stage. Flowers that were in the bud stage (stage 1) before simulated s
hipping lasted longer than flowers showing color (stages 2 and 3), reg
ardless of cultivar or chemical treatment. Combinations of STS and BA
did not increase PSFL compared to STS alone. Plants treated with 2 or
3 mM STS exhibited longer PSFL than nontreated plants; however, 2 and
3 mM were about equally effective. STS at 4 mM was phytotoxic in a pre
liminary experiment. Applying BA alone did not affect PSFL, but did im
prove postharvest flower opening on 'Meijikatar' plants about the same
as STS applied alone. The large flowering cultivars represented by 'M
eijikatar' and 'Meirutral' appear to be nonresponsive to BA. A star-sh
aped malformation was induced on 'Meijikatar' and 'Meirutral' plants b
y simulated shipping and was not prevented by STS or BA. Chemical name
used: N-(phenylmethyl)-1H-purin-6-amine (BA).