Agriculture Reference
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c) The anthers exert from the lemna and palea.
d) As the lemna and palea open further, the tips of the
feathery stigma become visible.
e) The fi laments elongate past the tips of lemna and palea.
f) The spikelet closes, leaving the anther outside. Anther
dehiscence (pollen shed) usually occurs just prior to or at
the time the lemna and palea open.
Pollen grains are visible for about five minutes after
emerging from the anther, whereas the stigma may be fertilized
for three to seven days. Rice is a self-pollinating plant, because
it is usually pollinated before the lemna and palea open to
release pollen into the air. Fertilization of the ovary by the
pollen grain is generally completed within fi ve to six hours after
pollination; at that point, the overy becomes brown rice. The
time interval for fl owering of an entire panicle is normally four
to seven days. A relationships between plant and soil factors
that control the availability and uptake of mineral nutrients is
that soil temperature affects nutrient uptake directly by altering
root growth, morphology, and uptake kinetics. Indirect effects
include altered rates of decomposition and ineral nutrient
mineralization, mineral weathering, and nutrient transport
processes (mass fl ow and diffusion) (Fig. 32).
It is noted that a fl ower-specifi c proline rich protein mainly
present in rice fl ower and accumulated abundantly during
the late stage of fl ower development which is associated with
cold tolerance in rice, a cell wall protein, playing a crucial role
in determining extracellular matrix structure of fl oral organs
(Gothandam et al. 2010).
In general the mechanism of cellular response to induce
cold stress in rice at the reproductive phase is similar to the
mechanism described earlier and is mediated via ABA synthesis
and the cascade of changes in metabolism to hinder the
