Impact of Combined Biological and Chemical Fertilizers on Yield and Nutritional and Biochemical Characteristics of Potato Cultivars (Solanum tuberosum L.)

Potato cultivation, as one of the most extensively farmed tuberous crops, requires a substantial supply of fertilizers. However, improper fertilizer application can significantly disrupt the soil ecosystem and increase heavy metal contamination. This study aimed to investigate the interaction effects of fertilization type (chemical, biological, and their combination), seed tuber weight (small (<= 75 g), medium (70-140 g), large (>= 140 g)), and potato cultivars (Sante, Arinda, and Savalan) on various morphological, physiological, nutritional, and biochemical traits of potato. The methodology employed a split-split plot design in the form of a randomized complete block with three replications over 2 years, 2019 and 2020. The results indicated that all studied traits, except for plant height, were influenced by the experimental parameters. Biological fertilization generally improved plant growth parameters (height, shoot number, leaf area index), tuber yield, and nutrient content (nitrogen, phosphorus, potassium) compared to chemical or no fertilization. Starch content was highest in medium-sized tubers and was particularly enhanced by biological fertilization in the second year. Factor analysis results revealed that Savalan cultivar along with biological and combined fertilization was associated with P and K content, tuber yield, plant height, chlorophyll content, and starch percentage. Furthermore, tuber yield positively correlated with the same mentioned parameters. Overall, Savalan cultivar generally outperformed the Arinda and Sante cultivars in most characteristics. Furthermore, solanine content was lowest with biological fertilization, especially in the Savalan cultivar. In conclusion, our findings demonstrate that biological fertilization, particularly for the Savalan cultivar, can enhance potato performance while reducing undesirable solanine content.