Effect of biochar use as a substrate on granadilla (Passiflora ligularis Juss.) growth parameters

The impact of biochar on soils has been demonstrated, including its improvements of physical, chemical, and biological properties that promote agricultural production. This study aims to evaluate the effect of biochar on the growth of granadilla (Passiflora ligularis Juss.) seedlings. For this research, biochar was obtained from the pyrolysis of agricultural waste in a conical flame curtain reactor at temperatures between 400ºC and 500ºC for 90 min. The different biomasses used consisted of cholupa (Passiflora maliformis L.) fruit shells, residues of guamo (Inga spuria) wood, coffee (Coffea arabica L.) husks, and rice (Oryza sativa L.) husks. The biochar produced was mixed with Jiffy® brand peat in doses of 5%, 10%, and 20% (v/v) for each of the four types of biochar, with a control of 100% peat. For each treatment, 100 seedlings were planted, taking 12 random samples of each at 43, 57, and 71 d after sowing. Data were analyzed using the Kolmogorov-Smirnov and Levene test, followed by a factorial analysis of variance, evaluating variables such as dry weight, root length, leaf number, stem diameter, and chlorophyll index. The biochar obtained from the coffee husk promoted further growth, but its effectiveness decreased at a concentration of 20%.