In the US, strongly recommended PGRE means you should explain in your application (in your Statement of Purpose, most likely, unless they have a special place in the application to explain it) why you didn't include it. Being an international student, where sometimes the PGRE test center is hard to get to, can be a good excuse. If you don't have a good excuse, you should send it. It won't hurt you anymore than not sending it in will; your score is not exactly terrible.
Elsewhere, there's no need for the PGRE at all, it's a test predominantly (exlusively?) used in the United States.
Source: UC Davis admissions chair, an institution who does not require the PGRE, though "strongly recommends" it.