BIOSTIMULANT POTENTIAL OF Trichoderma spp. IN THE CULTURE OF JAMBU
Acmella oleracea (L.) R. K. Jansen; Acmella ciliata (Kunth) Cass.; toothache plant; cropping system; biostimulation; secondary metabolism; Amazon.
Jambu is a leafy vegetable with enormous versatility of use, showing potential both for fresh food and for industrial exploitation, due to the biosynthesis of metabolites. However, its productivity varies according to the type of management adopted in the cultivation environment. Thus, the objective of this research was to evaluate the biostimulant potential of Trichoderma spp. in promoting growth, productivity and spilanthol concentration in local varieties of jambu. For this purpose, an experiment was carried out divided into two trials, where in trial I the characterization of biostimulated and non-biostimulated seedlings was performed. In the second trial, the seedlings were transplanted in a greenhouse, adopting a randomized block design, in a 3x4+3 factorial scheme, with four replicates, the first factor being composed of the jambu varieties and the second by the biostimulants, with three additional ones, without inoculation. In the seedling phase, we evaluated plant height, stem diameter and number of leaves. In the field, the days to flowering, physiological parameters, vegetative development, biomass production and spilanthol concentration were evaluated. The Jamb03-MIX treatment was grouped separately, due to the responses for height and diameter of the seedling collar. The physiological parameters were higher in Jamb-16, and the stomatal opening in this variety was influenced by the inoculation. There was precocity of flowering in Jamb-17 plants biostimulated with MIX. The growth characteristics and biomass production of the aerial part were higher in the Jamb16-IBLF006 and Jamb16-MIX treatments, influencing the grouping. The principal component analysis separated Jamb-03 based on inflorescence productivity and internal CO2 concentration. Jamb03-MIX had higher inflorescence production than the other varieties biostimulated with MIX. The spilanthol concentration in the inflorescences of Jamb17-MIX was higher than the additional. On the other hand, the responses of spilanthol in Jamb-03 and Jamb-16 were regulated by intrinsic factors of the variety. Therefore, we found that the inoculation of Trichoderma spp. in jambu can promote the development of more vigorous seedlings, with early flowering in the field, biomass accumulation, and modulation in spilanthol biosynthesis. However, the results are conditioned by the specificity of the interaction.