I'm going to purchase a DSLR for the first time.need maintenance information?

I'm going to buy a nikon's DSLR for the first time and i don't have any idea of its prevention from dust and fungus etc. So much money i'm putting in it and now i'm scared?

Nikon DSLR cameras are best always. As needed maintenance I think you should first concentrate with its lens clarity. Clear lens always.

I'm a Canon owner and only recommend what I own and therefore know… Others use Nikon and swear by them as well… Both are fine cameras.

If you store the camera properly, in a bag or case, in a closet or drawer when not in use I don't think you'll have any problems. I have cameras that I've been using for years, never a problem such as you describe.

Major maintenance is generally as and when needed.

As for dust, always use the lens caps (both ends), and the camera body cap. When changing lenses, get the lens ready first by twisting the body mount cover to it's off position, but leave it in place. Point the camera toward the ground, remove the body cap and quickly mount the lens after tipping off it's cap. The quicker you are the less likely you are to have dust issues.

Fungus is awkward, if it's going to happen it's going to happen. The best that you can do is try to make sure that if your local climate has a high level of humidity, that you keep your equipment in a humidity controlled environment. In parts of India if you had a high investment that might mean a dry cabinet of some type (expensive). Mostly though you can use "rechargeable" silica gel water traps, which do a fine job if your equipment is kept in a bag, box, or trunk with a restricted air flow.

I have at least one of these in each camera bag:
http://www.ebay.co.uk/...1085023699
when they change color you simply microwave the water out of them and they are good to go again.

The above by the way is a generic product, I'm not recommending that particular seller - it's only used as an example.