Abstract: Disclosed herein are transgenic plants comprising heterologous molecular chaperone genes and insecticidal Bacillus thuringiensis (Bt) genes capable of conferring enhanced Bt insecticidal activity to insects. The disclosure further relates to methods of producing transgenic plants, enhancing efficacy of a Bt toxin and controlling insect populations in areas of cultivation using transgenic plants co-expressing a heterologous molecular chaperone gene and a Bt gene.