The effect of soil biostimulant Agriful on the selected quantitative and qualitative parameters of carrot (Daucus carota subsp. sativus (Hoffm.) Arcang.)

The research task was focused on an important type of root vegetable – carrot (Daucus carota L.), cultivar ´Romance F1´ (family: Apiaceae). The main goal was to verify the application of soil biostimulant Agriful (based on humic and fulvic acids) and its impact on the yield potential and quality of carrot roots. Nowadays, it is the common need to intensify and increase crop production because of the growing human population and look for environmentally friendly cultivation methods. In general, biostimulants are biologically based products and their purpose is to stimulate the natural nutritional processes in cultivated crops. In the realized experiment, Agriful (treatment of 5 L/300 L water/ha) was applied twice per vegetation period by spraying over the pivot. The increase of average root weight after the application of Agriful was found, concretely about +4.47% compared to the control variant. The higher root weight after Agriful application resulted in a higher total yield of carrot about +2.84% compared to the control variant. The quality of consumable parts of carrots were evaluated based on the classification of roots into quality classes according to the valid standard for fresh carrot marketing (UNECE FFV-10). In the ´Extra class´, there was an increase in the average yield after the application of Agriful about +5.4%; The average carrot yield in ´Class I´ was decreased about -1.0% and the root ratio in the ´Class II´ decreased about -1.9%. The ratio of ´Non-standard´ carrot roots was lower about -2.5%. Based on evaluating qualitative substance content (total carotenoids, refractometric dry matter), the positive influence of the effect of Agriful application was found. The content of total carotenoids was higher about +8.7% compared to the control variant. The refractometric dry matter was higher about +4.1% compared to the control variant. The obtained results can be used in further research on biostimulants and it is possible to create clear recommendations for using Agriful for small growers. It should be useful to verify these results in another vegetation period for recommendation to large-scale producers of carrots.