Yield and Yield Components
Grain Yield
The maximum yield has achieved by applying
chitosan by seed soaking and soil application ; the average yield was 427.78 g/Tr, whereas the
control was 364.83 g/Tr. The statistically significant
differences were detected among treatments,
Figure 3(F). This result could explain that application
of chitosan by incorporation in soil showed the
maximum grain yield since chitosan- availability
periods in soil were longer than those of foliar
spraying. Moreover, chitosan had a positive ionic
charge which chemically bind with plant nutrients
that showed a negative ionic charge resulting in a
slowly released action in rice plants which closely
contributed to yield increasing. There were many
reports supporting this result such as the report of(8)
who found that panicle numbers and yield of wheat
(Triticum aestivum L.) were increased after
application of polymeric or oligomeric chitosan.
Boonlertnirun, et al. 2006 reported that rice yield
cultivar Suphan Buri 1 was significantly increased
over the control (no chitosan) after application of
polymeric chitosan at the concentration of 20 ppm.
Panicle Numbers Per Plant
The issue of panicle numbers is one of the
important yield components which directly affected
rice yield. No statistically significant differences
were found among chitosan application with different
methods including the control. The maximum
number of panicles has obtained from treatment
with seed soaking before planting and soil
application later, whereas the treatment with seed
soaking in chitosan solution showed the minimum
number of panicles, Figure3(F). Lu, et al. 2002
found that the panicle numbers of rice were
increased after watering with chitosan at the rate of
0.4 g /50 cm3
(chitosan: water )