Usually it's just בקר, but both are correct. Most people say בקר (backar) because it's shorter.
Morning will be written בוקר (bocker) most of the time, בקר (still bocker) is a bit more formal way to write it.
Fun fact: the word בוקר also means a cowboy.
Imho, it's no good to use this word and yet in such context here because it may sound disgusting to the ear of Hindu, and maybe, some Hindu guys study Hebrew here. Btw, I am not Hindu, I just share my thoughts.