Olive oil quality influenced by biostimulant foliar fertilizers

Autor: Meriem Tekaya, Amel Mguidiche, Mouna Aïachi Mezghani, Faouzi Attia, Khouloud Annabi, Imed Cheraief, Beligh Mechri, Olfa Dabbaghi, Imen Zouari, Foued Laabidi, Mohamed Hammami
Rok vydání: 2020
Předmět:
Zdroj: Brazilian Journal of Biological Sciences. 7:3-18
ISSN: 2358-2731
DOI: 10.21472/bjbs(2020)071501
Popis: Foliar fertilization has been used as an important tool to meet the tree nutrient demand and to be an environmental beneficial with the use of little quantities. Actually modern fruit trees physiology is focused on the stimulation of plant cell development and fruit production using biostimulants. In olive trees, few products have been used for improving oil quality. For this purpose, two biostimulants products have been tested and used simple or combined with a third product rich in nitrogen. The treatments were classified to: T1 (rich in nitrogen) and biostimulants treatments as following T2 (combination of boron, magnesium, sulfur and manganese associated with seaweed) TNi (biostimulant combining a protein extract with a calcium base), T12 (combined application of T1 and T2) and finally T12Ni (combined application of T1, T2 and TNi) with a control treatment CON (without foliar fertilization). All these foliar nutrients were sprayed during two successive years on trees issued of Chemlali cultivar cultivated in rain-fed conditions of central Tunisia. Biochemical parameters of the olive oil, like physiochemical characteristics, fatty acid profile total polyphenols, ortho-diphenols, chlorophyllic and carotenoids pigments were analyzed annually after the application of these foliar compounds. All the olive oils issued from the treatments were classified as extra virgin and the physiochemical parameters were sensitive to foliar fertilization except for some parameters. Quantitative changes were observed in the pool of the fatty acids composition and the treatment TNi (rich in calcium) increased significantly the percentage of the monounsaturated fatty acid (MUFA) C18:1 as well as the ratios C18:1/C18:2 and MUFA/polyunsaturated fatty acids (PUFA) during the first year of experimentation. This treatment induced also an increase in the total polyphenols concentration. An annual variation between treatments has been observed according the polyphenols concentration and othodiphenols which can be influenced by climatic conditions principally in rain-fed conditions. This study highlighted the effect of the nutrient availability cumulated after two years of foliar application on the olive oil quality.
Databáze: OpenAIRE