Enhancing the Quality and Yield of European Borage (Borago officinalis) by Simultaneous Application of Granulated Compost, Vermicompost and Mycorrhiza

The application of organic fertilizers alone or in combination with bio-fertilizers is important for sustainable agriculture, healthy agricultural production and restoring soil quality. Compost, vermicompost and mycorrhiza amendments could improve soil quality and plant yield. However, little is known about their impact on yield and quality of European borage (Borago officinalis L.). To evaluate the effects of vermicompost, granulated compost, and mycorrhiza on qualitative and quantitative traits of B. officinalis an experiment was carried out based on a randomized complete block design arranged in a factorial experiment with three replications. Organic fertilizers in five levels (0, 5 and 10 t/ha vermicompost and 3 and 6 t/ha granulated compost) and mycorrhiza (Glomus mosseae) in two levels (with and without) were considered. It was shown that the effects of organic fertilizer and mycorrhiza application on nitrogen content were significant in such a way that the maximum nitrogen content was obtained by 10 t/ha vermicompost and mycorrhiza inoculation treatment. The main effects of organic fertilizer and mycorrhiza on phosphorus and potassium contents were also significant. The maximum values were obtained when 10 t/ha vermicompost and mycorrhiza were applied together. Total chlorophyll content, flower-bearing branches, mucilage, and phenol were measured in all three harvests. The results indicated that the interaction effect of harvesting time, organic fertilizer, and mycorrhiza was only significant on chlorophyll content. The maximum chlorophyll content (0.958 mg g-1 fresh weight) was detected in the third harvest when 10 t/ha vermicompost and mycorrhiza were applied. Maximum mucilage content (4.23%), phenol content (5.07%) and flower-bearing branches (57.45 g m-2) were obtained by 10 t/ha vermicompost treatment. The results suggested that chemical fertilizers could be replaced by organic fertilizer and mycorrhiza to reduce soil and water contamination in the agroecosystems.