Abstract:
During peak planting time in commercial tuberose cut flower production lack of
seed materials occasionally occur. Most producers also source planting materials
which have not been adequately stored resulting in poor performance of the crop.
For improved productivity in tuberose cut flower value chain, ways of increasing
the availability of planting materials and improving the growth performance need
attention. This study examined the effects of subsequent warm temperature
storage after low temperature treatment of tuberose bulbs on growth, sprouting
and flower quality. The experiment was laid in a split plot arrangement in a
completely randomized design. Tuberose bulbs were stored in a biotron at 5ºC or
10ºC for 3 months with subsequent temperature storage of 20ºC for 0, 2, 4 or 6
weeks. The main effects were pre‐treatment temperatures at 5 or 10ºC, whilst
subsequent temperature storage treatments constituted the sub‐effects. Days to
sprouting were significantly earlier ( 14.9) when tuberose bulbs were pretreated at
10ºC followed by 20ºC subsequent temperature storage for 6 weeks compared to
51.1 at 5ºC pretreatment with no subsequent temperature storage. The highest
percent sprouting (99.2%) was obtained with 10ºC pretreatment followed by 20ºC
thawing for 6 weeks. Pre‐treating tuberose bulbs at either 5ºC or 10ºC then
planting directly resulted in 69.3% and 88.3% sprouting, respectively, whilst similar
pretreatments resulted in 70.0% and 81.2% flowering. The number of days to
flowering were significantly (P<0.05 ) reduced (110.8) at 10ºC pre‐treatment
followed by 20ºC subsequent thawing for 6 weeks compared to 143.1 at 5ºC
pretreatment with no thawing respectively. Stem length of inflorescences
significantly (P<0.05) improved to 106.8 cm at 10ºC with thawing at 20ºC for 6
weeks compared to 98.2 cm at 5ºC pretreatment and no thawing respectively.
Number of florets per spike also significantly (P<0.05) increased to 42.4 compared
to 34.9 for similar treatments. Storage of tuberose bulbs at low temperatures
followed by warm subsequent storage for 2, 4 or 6 weeks besides improving
sprouting and quality of flowers could enhance the availability of planting materials
for crop production. The planting materials could be bulked with possibility of
commercial exploitation.
