Agriculture Reference
In-Depth Information
Source Cells Sink Cells Cereal Endosperm Cell
Fig. 34
Starch formation in grains.
activities correlated negatively with ethylene concentration.
It is concluded that seed weight of inferior spikelets can be
improved in rice panicle by increasing activities of starch
synthesizing enzymes through manipulation of ethylene
production, while genotypic difference in seed weight remains
beyond manipulation (Mohapatra et al. 2009).
Activities of AGPG, pyrophosphorylase, soluble starch
synthase and starch branching enzymes increased fi rst and
then fell down during grain development. Different varieties
had different enzymes activities at the same grain fi lling stage
and differed in the time when enzyme activity reached a peak
value. Activities of ADPG pyrophosphorylase and soluble
starch synthase respond dully to the temperature but starch
branching enzyme was more sensitive to the temperature and
its activity declined when temperature was too high or too low
(Zheng-xun et al. 2005).
Starch synthesis in amyloplast in developing grain of rice
may be given below. It suggests that sucrose transported is
the starting material in association with sucrose synthase (SS)
undergoes change to hexose phosphates and biphosphates.
