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In vitro corm formation and flowering and ex vitro acclimatization
watering regime at the time during which these experiments where conducted and
plants were watered every second day with 500 ml of water.
Corms of R. minutiflora and R. sabulosa were planted in plastic planting trays with a
1:1 ratio of potting soil and sand. For each species, 6 corms were placed in 6 trays.
The trays were placed in the mist-house for 24 h, after which they were moved to the
greenhouse. The trays were only placed in the mist-house for this short period of
time because all corms were necrotic after only two weeks in an initial experiment
were 2 trays with 6 corms each where placed in the mist-house, suggesting that
these conditions are too moist.
In another experiment corms of R. sabulosa were planted in clay pots with a 1:1 ratio
of potting soil and sand. Because of the limited number of pots, 4 corms were placed
in each pot and 30 pots were used. These pots were placed in a growth chamber
with high light (190.1 µmol m –2 s –1 ) maintained at 20°C.
Healthy rooted plantlets of R. minutiflora and R. sabulosa that did not produce corms
during corm formation experiments were planted in plastic planting trays with a 1:1
ratio of potting soil and sand. For each species, 6 plantlets were placed in 5 trays.
The trays were placed in the mist-house for 24 h, after which they were moved to the
greenhouse.
A small experiment was conducted with the remaining corms formed in vitro at 10 °C.
Four corms were placed in a clean plastic container with autoclaved vermiculite
moistened with 50% Hoagland’s nutrient solution. The containers were placed in a
growth chamber set at 20°C with a 16 h photoperiod of 12.5 µmol m –2 s –1 irradiance
for two months. The rest of the corms were used for a viability study. The viability of
ten corms larger than 5 mm in diameter were tested according to the method of
WAGNER (1984).
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