What is the optimum number of directory submission per day?

Who says that? Where you have seen such?

Who said you that Google, Bing or Yahoo can monitor your directory submission procedure?

 

Fiction.

The two best pieces of advice from the OP (readezarchive's if you really need to submit to a directory that is).

And quality backlink doesn't mean on a pages with PR, but from authority sites (the page can be fresh and pr0, doesn't matter). (PR is a meaningless number that fluctuates a lot, especially with all these recent updates - a large knock-on effect to PR.)

 

Good information, if we do more than 30 submission then it will be spam for one site only..

 

Not true.
Search engine can't monitor your directory submission.

 

50 per day.

 

atleast 50 per day....

 

Well, according to me 10-20 directory submissions would keep you on the safe side. However the directories which you submit your links in should be legit and of high quality. No matter if you submit even lesser links, but just make sure the links are natural and of good quality

ATB!

 

Thanks you friends your replies. It really useful. I think less than 30 per day safe.