• First field study of Trichoderma effects on spilanthol in jambu in the Amazon. • Trichoderma increased shoot spilanthol in Jamb-17, with reduced biomass. • Inflorescence spilanthol in A. oleracea increased >20 % after inoculation. • Spilanthol responses depended on jambu variety and Trichoderma strain. The toothache plant ( Acmella spp.), commonly known as jambu, produces substantial amounts of spilanthol, a secondary metabolite with notable biological properties. This study aimed to evaluate the effects of biostimulation with Trichoderma spp. on spilanthol concentration in the shoots and inflorescences of different jambu varieties. Extracts from three varieties (Jamb-03, Jamb-16, and Jamb-17), with and without fungal inoculation, were analyzed for spilanthol content using ultra performance liquid chromatography (UPLC). Biostimulation with IBLF 1236 (B3) and a native strain mixture (MIX, B4) modulated spilanthol levels in Jamb-03 and Jamb-17. In shoots, Jamb-17 treated with B3 showed the highest spilanthol concentration (7.90 mg/g dry mass), whereas in inflorescences, Jamb03-B3 and Jamb17-B4 exhibited increases of 41.8 % and 24.02 %, respectively, compared to uninoculated controls. Although Jamb-16 showed no spilanthol modulation, increased shoot biomass resulted in higher total yield. These findings provide promising insights into spilanthol modulation in jambu varieties biostimulated with Trichoderma .
Andrade et al. (Thu,) studied this question.