Dear Geetha ji, I believe this to be Ipomoea eriocarpa, a tiny morning glory.
I too had put this for ID here in this Indiatreepix group about a month back; the mail thread with subject line: ¿ Tiny Convolvulaceae member ?
Nayan ji had helped identify it.
Creating Awareness about Indian Flora & Fauna:http://en.wikipedia.org/wiki/User:Jmgarg1
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