Effect of Biochar Amendment and Organic Fertilization on the Yield and Nutritional Quality of Artichoke (Cynara cardunculus L.)

Organic fertilization is gaining importance as an alternative to chemical fertilization. However, the effects of organic products on crop quality need to be characterized, especially in biochar and derived products. Therefore, the effect of enriched biochar supplied with an organic fertilizer (biochar) on the yield and nutritional compounds of artichoke (Cynara cardunculus var. Scolymus) heads was analyzed and compared to inorganic conventional fertilization (control). For this purpose, the number of fruits and their weights were determined, along with the nutritional properties of artichoke heads, such as mineral content, fatty acids, phenolic compounds, and flavonoids. The results showed that biochar increased crop yield, as registered by the higher number of marketable or commercial artichokes compared to the control. Additionally, biochar-treated plants exhibited significantly higher contents of Ca, Mg, and S in the artichoke heads, but they had a decreased content of Co, Cu, and Zn. The fatty acid content in the biochar-treated artichokes was also significantly higher, primarily due to the presence of palmitic acid. Conversely, the contents of phenolic compounds (e.g., flavonoids) were negatively and significantly affected by the application of biochar. In conclusion, the application of biochar as a soil amendment in combination with organic matter for growing artichokes in the semiarid Mediterranean area (e.g., Murcia Region) favored an increase in yield without compromising its nutritional composition. Further developments to establish protocols for the extended use of biochar in this agri-food production area are guaranteed.