Chitosan is a natural biopolymer which stimulates growth and increases yield of plants as well as
induces the immune system of plants. The objectives of this study were to determine appropriate
applications for increasing of the rice yield. The experiment was performed with randomized complete
block design ( RCBD) with four replications. Four treatments were done as follows : no chitosan
application, seed soaking with chitosan solution, seed soaking and soil application with chitosan solution
and seed soaking and foliar spraying with chitosan solution. The results showed that application of chitosan
by seed soaking and soil application four times throughout cropping season significantly increased rice yield
over the other treatments whereas application by seed soaking and spraying the foliar four times tended to
show an ability on disease control. However, it did not show statistically significant differences when
compared with the control.