(I play in Portuguese language so the translation can't be very good! XD) very well, I'm in doubt about the 2nd status of the construction (+3 Food on Original Empire Population), because only the effect per level appears, the second status would it be a "hidden status" (not visible or am I not getting the benefit)?

I'm playing with the united empire, should I have in my home solar system only pops from the empire for the 2nd effect to be applied or is the effect already being active?

The first effect is based on System level. Level 1 System = +25 Food. Each upgrade to the system adds 25 Food Production for a total of +100 at level 4. The secondary effect basically adds a +3 Food buff to your Population, in this case United Empire, on the planet. So if you have a system that is level 2 with one colonized Terran planet(8 base Food) and 3 Imperial population, your Food Production ought to be 50 + 33(3 x 11) = 83. This doesnt factor in other Food buffs. If you're not getting the second buff, its likely due to the fact you dont have any Imperials on the system that has that unique improvement.

thanks! The bonus system by level I understood, I just wanted to know if the secondary bonus is visible or not, because even if you put the main pop in the production / consumption summary, there is no effect, of +3 for each pop, I noticed that this is not the first pop-based effect that is not counted.