Azolla is used to supplement the N demand of the
rice crop. The present study indicated that dual cropping
of Azolla reduced CH4 flux and yet increased
grain yield similar to that of urea application. The decrease
in CH4 efflux in plots with dual crop of Azolla
could be related to the release of oxygen in the standing
water by the growing Azolla leading to less reduced
conditions in the soil. This suggests the possibility of
practicing Azolla dual cropping for sustaining higher
yields and protecting the environment by minimizing
the CH4 flux from flooded rice paddies.