Rice (Oryza sativa L.) is the most important crop of south east Asia
popularly referred to as the rice bowl of the world. India has the
largest area under rice in the world it ranks second in production
falling far behind China, which has production of about 200 m tons.The
reason for very low productivity in Bihar centres round the fact that
rice cultivation in Bihar is mostly rain dependent. Both raising nursery
and transplanting seedlings are on the mercy of monsoon, which is
extremely erratic in onset, distribution, intensity and cessation.
Invariably the seedlings overgrow in the nursery awaiting for rains
adequate to perform puddling operations. As a result of use of overgrown
seedlings, at times, the crop starts flowering soon after flowering
reducing the yield tremendously. Some of the times it becomes even
difficult to raise seedlings due to very delayed and erratic monsoon.A
very large number of herbicides are there which have been observed to
have effective control of weeds in direct seeded rice. However,
selecting a particular herbicide or its combination with mechanical weed
management require thorough probe.