Which medicine i use for this

Dear Sonu I have not seen such a rice variety so far. Blackening of the seed coats of the grains looks to be varietal charecter. Please confirm. If you are a regular grower of this variety , you will know this factor.

If you have planted some kind of black grained spiky rice then its OK otherwise these plants are wild rice you can't even harvest them because their grains will detach from mother plant and fall down on soil soon. Plant specifications may vary according to variety of wild rice. Mostly their leaves specifies less wide than leaves of rice we plants and grain's color may black or much like farming rice grains. YOU SHOULD REMOVE THEM. They override our crops year over year. One of wild rice's survival skill is all of their grains on soil never germinates at ones or one session and remaining ungerminated grains not get damaged due to mud, rain, temperature fluctuation etc for many years and remains as backup for existence of their variety. Above I have pictures of normal rice like wild rice and I'll get photos of black variety of wild rice tomorrow. In our area we know all these varieties as KARGA.

As grains get matured it becomes black. Here are two varieties of wild rice.