| Summary: | 碩士 === 國立中興大學 === 植物學系 === 83 === Measurement of diurnal changes of stomatal movement indicated
that stomates opened at about half past seven in the morning
and apertures were increased rapidly . The maximum aperture
opening was around nine o'clock in the morning and maintained
opening until two o'clock in the afternoon .The stomatal began
to close about two o'clock in the afternoon and apertures were
decreased rapidly. The stomatal almost completely closed about
four o'clock in the afternoon and no night opened phenomenon
was observed . Both fertilization treatments have greater
degree of stomatal aperture than no fertilization ones. Both
fertilization treatments had greater total chlorophyll contents
than no fertilization. Because of this, Tainung 67 , Taikeng 2
and Woogen had greater oxygen evolution rates under
fertilization. So fertilization can increase total chlorophyll
contents and rise the rate of photosynthesis.However , Taiseng
1 had no differences in the oxygen evolution rate with
different nitrogen treatments. Fertilization increased the
photosynthesis rates as well as Rubisco activities resulted in
accelerating whole carbon metabolism . It's that achieves
carbon and nitrogen equilibration thereby accelerates nitrogen
metabolism . So increased nitrate reductase and nitrite
reductase activities were observed under fertilization. In
higher plants, ammonia is mainly assimilated by GS/GOGAT
pathway which produces glutamine and glutamate . Addition of
ammonium salts via fertilization should produce higher amount
of glutamate due to the increased enzyme activities in the GS/
GOGAT pathway . Our results showed that indeed glutamate had
the highest content among 20 amino acids of all four rice
varieties .
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