In Gr59c^Δ homozygous labellar I-a sensilla, the novel electrophysiological responses to Theophylline and Umbelliferone are enhanced by the Scer\GAL4^Gr89a.2-driven expression of Gr28a^Scer\UAS.cDa, but not Gr36a^Scer\UAS.cDa or Gr28b^{Scer\UAS.A.cDa}, and by the Scer\GAL4^Gr66a.1.8-driven expression of Gr22b^Scer\UAS.cDa, whereas the increased response to Caffeine is enhanced upon Scer\GAL4^Gr89a.2-driven expression of Gr28a^Scer\UAS.cDa, suppressed upon Scer\GAL4^Gr89a.2-driven expression of Gr36a^Scer\UAS.cDa and unchanged upon Scer\GAL4^Gr89a.2-driven expression of Gr28b^{Scer\UAS.A.cDa} or Scer\GAL4^Gr66a.1.8-driven expression of Gr22b^Scer\UAS.cDa; the Scer\GAL4^Gr89a.2-driven expression of Gr28a^Scer\UAS.cDa in these mutant sensilla also leads to novel responses to Azadirachtin and Coumarin, and leads to significantly increased responses to Aristolochic acid, Saponin and Strychnine nitrate salt; the Scer\GAL4^Gr89a.2-driven expression of Gr36a^Scer\UAS.cDa in these mutant sensilla leads to novel responses to D-(+)-sucrose octaacetate, Sparteine sulfate salt, coumarin and Azadirachtin, leads to significantly increased responses to Saponin and Aristolochic acid, and leads to significantly decreased responses to Berberine chloride and Caffeine; the Scer\GAL4^Gr89a.2-driven expression of Gr28b^{Scer\UAS.A.cDa} in these mutant sensilla leads to a significantly increased response to Aristolochic acid; the Scer\GAL4^Gr66a.1.8-driven expression of Gr22b^Scer\UAS.cDa in these mutant sensilla leads to novel electrophysiological responses to Azadirachtin, Sparteine sulfate salt, Escin and D-(+)-sucrose octaacetate and to the virtual elimination of the responses to Aristolochic acid, Saponin, Berberine chloride and Strychnine nitrate salt.