Impact of Propolis Extract as Foliar Spray On Growth, Yield and Some Chemical Composition of Spinach (Spinacia Oleracea L.) Plants Grown Under Calcareous Saline Soil

Abstract

This experiment was suggested to study the beneficial effects of foliar application with propolis extract at the rates 0, 6000, 7000, 8000 and 9000 mg/L solution used as foliar application to spinach seedlings on growth, yield and some chemical constituents of spinach plants (Spinacia oleracea L.) grown under calcareous saline soil conditions. All experiments were achieved during the two successive seasons of 2016 and 2017. Results showed that increasing the rates of propolis extract as foliar application increased the growth parameters of the treated plants. The best result was obtained by the rate (8000 mg/L) as a foliar application in both seasons of the study. The same trend was also observed regarding all studied chemical constituents, i.e. chlorophyll a, b and total carotenoids concentration, anthocyanine, total carbohydrates, total and reducing sugars, total free amino acid, free proline, crude protein, total indoles, total phenols, N, P and K in leaves. Thus, the coincident application of propolis extract at (8000 mg/L) as foliar application ingredient is recommended for improving growth, yield and chemical composition of spinach plants and for overcoming the adverse effect of saline conditions.