Comparative Study on the Influence of Organic Fertilizer and Soil Amendments on Evening Primrose ( Oenothera biennis L.)

摘要

Background: This study was done in the light of concept safety production of medicinal and aromatic plants. Materials and Methods: This study was conducted in open fields for two seasons continuously to compare the effects of organic fertilizer, soil amendments, a mixture of them and chemical NPK fertilizer (control) on growth parameters, floral characteristics and chemical constituents of Oenothera biennis L. (evening primrose) plants. Results: The outcome data pointed out that mixture of organic fertilizers (cattle manure and humic substances) and soil amendments (zeolite and magnetite) led to significant increment in morphological growth (plant height, number of branches, number of leaves, leaves area, leaves fresh weight and leaves dry weight), floral characteristics (number of flower, number of capsules, seed yield as well as health index) and chemical composition symbolized in plant pigments, total carbohydrates, net photosynthesis, stomatal conductance, water use efficiency, crude protein, total phenolics, N, P, K%, moreover indigenous hormones characterized in Indole Acetic Acid (IAA), gibberellic acid (GA3), cytokinins (CK) and abscisic acid (ABA), fixed oil content in seeds and oil yield per hectare in comparison with the recommended dose of chemical fertilizer NPK (control) under the same conditions. From an economic view, the feasibility study of experiment clearly indicated that mix of organic and natural fertilizers proven its value and potential to achieve maximum profitable returns. Conclusion: These results disclose that mixture organic and natural resources of fertilizers could reduce or replace the addition of chemical fertilizers, accordingly improve the quality and quantity of medicinal and aromatic plants, besides minimizing economic costs and pollution of the agricultural environment.