There aren't any growth-rate influencing race picks. You could argue indirect affects for Environmental (cheaper terraforming), Creative (better chance of getting pop techs), and Research (faster to research those techs) picks, but none of them do anything directly.
Excess Bio doesn't do anything for pop growth; it's just turned in to AUs. But not having enough food will, of course, lower growth rates drastically; IIRC, it won't go negative till the planet drops under 50% of needed food, though your people will get unhappy anyway before you get that low.
Some factors that affect any region's pop growth is the ratio of pop to max pop, plus the planet's overall density level (the max pop displayed is actually the maximum tolerable amount of people on the planet; what your citizens consider desirable is actually lower. You can find the two turning points in density on the demographics tab). Terraforming zone may have an affect too (beyond the indirect affect of changing max pop, that is); I'm not sure.
There aren't any race picks that affect pop growth, but races do have hardcoded multipliers. The Silicoids and Psilon are slower (85% and 90% normal respectively, IIRC). Some races are faster; the Grendarl have 125% normal growth, the other two Saurians have 110%, and both Insecta get bonuses too (With Tachidi being ultra-fast; 135% of normal!).
Also, remember that not all growth stays in its own region, or even its own planet. People love to migrate to other regions, or other planets in the same system. Inter-system migration is also possible if there's a desirable planet.
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