i'm not sure what you mean by low income. do you mean welfare? as in the government gives him money for living expenses? if so, then he won't be eligible to sponsor you. sponsors can not be on welfare.
if you mean he earns a low income from other sources, not including welfare, then it doesn't matter. there is no income requirement for spousal sponsorship. In the application though, CIC will want to know how he plans to support you while you get on your feet. examples are money saved, support from family, etc. Welfare is not an option. they want to be sure you WONT be going on welfare when you get to canada.