Question
can i usehot water for irrigation in green house where i am growing cut flowers like lily and carnation idia is to increase soil temperature during winters   
   thanks

Answer
Thanks for your question.
The plastics used in the manufacture of irrigation products and pipe can withstand the temperatures of household hot water. I would be more concerned with the effect on the plants. Warm water would be fine, however hot water could burn/shock the foliage or roots.
I would use a temperature mixing valve which prevents scalding. Most modern shower valves are this type, they only allow water to pass up to a certain temp. I'm sure you local plumbing supply shop could help with the selection.
Good luck, Matt