Effect of vermicompost application strategies on field strawberry healthiness, yield and fruit quality

It is recommended to use vermicompost as an organic fertilizer to supply nutrients and bioactive compounds for plant growth and to improve soil quality, while the best strategy of application is still unclear. The effects of vermicompost, implementing different application strategies, on strawberry healthiness, yield, fruit size and chemical properties, were studied in this investigation. The research was performed at the Institute of Horticulture, Latvia from 2016 to 2017. Several treatments were evaluated: 1) only inorganic mineral fertilization was applied (control); 2) vermicompost was applied at planting in holes with a dose of 100 mL plant^‑1 and mineral fertilization was applied during growth; 3) vermicompost was applied at planting in holes with a dose of 100 mL plant^‑1, no mineral fertilization was applied; 4) vermicompost was spread two times per season around plants with dose of 50 mL plant^‑1, no mineral fertilization was applied. Strawberry was grown on open field in rows with application of straw mulch between rows. No chemical plant protection products were used. The evaluated vermicompost application strategies had similar impact on strawberry productivity and fruit size to application of mineral fertilizers. Results showed reduced amount of rotted fruits and decreased common leaf spot disease severity in treatments with vermicompost application. Significant differences in fruit chemical content were observed among the treatments. Application of vermicompost promoted the increase of soluble solid content in fruits and reduced titrable acidity.