Abstract:
In vitro
pollen germination of three tropical tree species,
viz.
Spathodea campanulata,
Bauhinia purperia
and
B. racemosa
was done to know the effect of growth regulators a
nd
time on pollen germination. Three concentrations, i
.e. 100, 200 and 300 ppm of four
growth hormones (IAA, IBA, GA
3
and Kinetin) and sucrose (5 and 10%) alone were use
d
as germination medium. The results revealed that po
llen germination under control
condition is very low and oscillating between 4.6±1
.2 and 17.8±3.2%. The growth
hormones and sucrose was found effective inducing p
ollen germination. IAA and IBA
were found effective for both species of
Bauhinia
whereas GA
3
and kinetin were found
suitable for
Spathodea campanulata
. Maximum germination was recorded in the initial
24h of setting experiment, which further declined i
n 48h and was recorded very less and
even 0.0% after 72 hours of treatment. There was si
gnificant (< 0.0001) effect of time,
hormone and species on pollen germination. Sucrose
has shown good response (43 to
64%) in all selected tropical tree species. All the
three tree species are cross pollinated,
which depend on the variety services of pollinators
. Low %
in vitro
pollen germination in
control condition in
Spathoda campanulata
and
Bauhinia purpurea
reflects that both
species are prone to pollination and fertilization
failure if appropriate pollinators and
receptive stigmas are unavailable to them early aft
er anther dehiscence.
Keywords:
Gibberellic Acid, Pollen Production, Pollen viabil
ity,
Spathodea
,
Bauhinia
.
