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University
of Hawaii
Horticulture Digest #91, March 1990
Dendrobium Susan Takahashi, UH999 --
A seed-propagated flowering potted plant cultivar
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A cross between a tetraploid Dendrobium Evelyn
Nakasato and an amphidiploid D. Jaquelyn Thomas was made in
May, 1981 with the objective of developing a winter flowering,
seed propagated, cut flower cultivar. The offspring flowered
throughout most of the year. However, the yield as not as
high as the Jaquelyn Thomas type cultivars released earlier
by the University of Hawaii, and the bud drop percentage was
relatively high. The purple flowers (Red-Purple RHSCC72A)
of this cross were slightly larger than those of UH503 and
UH507. Also the relatively short stature and year round flowering
were considered desirable features as flowering potted plants.
The cross was repeated in August, 1984 (K999)
and again in February, 1985 (K1071) to evaluate the offspring
as flowering potted plants. The monthly spray yields for both
crosses are shown in Tables 1 and 2 and in Figure 1. Flowering
was obtained throughout the year for both years of evaluation.
Plants with at least two sprays in any given month were obtained
for most of the individual offspring.
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Table 1. Monthly and annual spray yield and
number of saleable plants* of Dendrobium Susan Takahashi, K999 (based
on 24 plants).
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Month
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1987 - 1988
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1988-89
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No. of sprays
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No. saleable plants
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No. of sprays
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No. saleable plants
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September
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9
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2
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9
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3
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October
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4
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0
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8
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2
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November
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11
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4
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6
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1
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December
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0
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0
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7
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0
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January
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14
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5
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4
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1
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February
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5
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0
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11
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3
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March
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5
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2
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9
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2
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April
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3
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1
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12
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3
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May
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7
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1
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7
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1
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June
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6
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1
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21
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7
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July
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15
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3
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27
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9
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August
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16
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6
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26
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10
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TOTAL
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95
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25
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147
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42
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*Saleable plants are those with at least two
sprays per plant. The total number of saleable plants exceeds 24
because plants were saleable during more than one month.
| Flowers lasted remarkably well on the plants.
The half life of sprays recorded from September to December,
1989 averaged 64.4 days. The half life was determined as the
number of days from the opening of the first flower until half
of the flowers on the same spray wither or drop. The long lasting
purple flowers, wide seasonality, uniformity, and short stature
are attributes of UH999 as a seed-propagated, flowering potted
plant cultivar. |
Table 2. Monthly and annual spray yield and
number of saleable plants* of Dendrobium Susan Takahashi, K1071
(based on 24 plants)
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Month
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1987-88
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1988-89
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No. of sprays
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No. saleable plants
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No. of sprays
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No. Saleable plants
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September
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1
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0
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7
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1
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October
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9
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1
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12
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3
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November
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8
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0
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5
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1
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December
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2
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1
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5
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1
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January
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1
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0
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1
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0
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February
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10
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3
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3
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1
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March
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6
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1
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7
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2
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April
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6
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2
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4
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1
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May
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4
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1
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5
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1
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June
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10
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2
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12
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3
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July
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6
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2
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14
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4
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August
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10
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3
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24
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10
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TOTAL
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73
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16
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99
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28
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*Saleable plants are those with at least two
sprays per plant. The total number of saleable platns exceeds 24
because plants were saleable during more than one month.
The
characteristics of UH999 (=K999, K1071) are as follows:
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Natural spread of flowers
– height (inches)
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2.4 ± 0.1
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Natural spread of flowers
– width (inches)
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2.5 ± 0.2
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Pedicel length (inches)
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1.7 ± 0.2
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Scape length (inches)
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6.9 ± 1.3
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Spray length (inches)
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18.0 ± 4.3
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Number of flowers per spray
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11.9 ± 3.9
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Half life of sprays on plants
(days)
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64.4 ± 9.4
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Vase life – half life of
cut sprays (days)
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11.0 ± 5.3
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Plant height (inches)
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21.4 ± 3.1
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Percent bud drop
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5.9
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| The bud drop
percentage was 5.9 which is considered marginal for cut flower
purposes. The vase life (half life) was 11.0 days which is comparable
to that of UH cut flower cultivars. Thus, during the winter
months, besides its major use as potted plants, UH999 might
also be used for cut flowers or for leis.
This cross
between D. Evelyn Nakasato and D. Jaquelyn Thomas was registered
with the Royal Horticultural Society as D. Susan Takahashi.
The repeat cross is being released to dendrobium growers association
in Hawaii as D. Susan Takahashi, UH999.
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Fig. 1. Monthly spray yields of Dendrobium Susan
Takahahi, K999 and K1071.
H.
Kamemoto, T.D. Amore, and N C. Sugii
View
98-cell tray seedling price list
View
58-cell tray seedling price list
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