Photosynthetic activity of olive leaves before and after treatment with an experimental mixture of pesticides

The article presents the results of evaluation of chlorophyll fluorescence of leaf blades for cultivars of olive (Olea europaea L.) before and after pesticide treatment. Five cultivars were compared, namely ‘Bidza’, ‘Kaliniot’, ‘Kokermadh I Berat’, ‘Nisiot’, and ‘Pulyazekin’. The photosynthetic activity of the leaves was studied under native conditions (control), as well as after 24 (Variant 1) and 72 (Variant 2) hours exposure to an experimental mixture of chemicals consisting of the “Fufanon” insecto-acaricide (manufacturer and registrant – “Cheminova A/S”, Denmark), a fungicide with an additional bactericidal action of “Fitolavin” (manufacturer and registrant – “Pharmbiomedservice”, Russia.), and the “Falcon” fungicide (manufacturer and registrant – “Bayer” Germany). Under cultivation in open ground (ex situ) in the collection plantings of the Nikita Botanical Gardens, most active production processes were found in the ‘Kaliniot’ and ‘Kokermadh I Berat’ cultivars, as evidenced by the high coefficients of the maximum (0.80 and 0.74 relative units) and effective (0.47 and 0.41) photochemical quantum yield of PSII, photosynthetic activity (0.65 and 0.73), and fluorescence decay coefficient (1.86 and 2.55). After exposure to an experimental mixture of chemicals, no significant changes in the maximum and effective photochemical quantum yield of PSII, photosynthetic activity, and fluorescence decay coefficient were observed. This indicates the absence of a negative effect of chemicals on the activity of photosynthetic apparatus of the leaf in the olive cultivars used in the study.