When to pay tax on interest income?

Hello friends,

I have salary income and interest income from bonds/company deposits. TDS has been deducted on salary income.

I have not paid any tax till date on interest income. My  bonds are of more than 5 L value and hence are visible in last year's form 26AS under AIR Transactions. So I need to pay tax on its interest income to avoid getting notice.

My question is when and how do i have to pay tax - before 31-3-14(end of fin year in which i got interest)  or 31-7-14(last day of filing return)?

Also how do I pay tax online?

I have searched a bit and found that I have to pay tax before 31-3-14 and aschallan no 282 > 0024 Interest tax > 300 self asssesment tax. is this correct?

Pls confirm.

Thanks.