EFFECT OF DIFFERENT SOURCES OF FERTILIZERS ON GROWTH, FLOWERING, AND CHEMICAL COMPOSITION OF SOME Hibiscus rosa-sinensis CULTIVARS.

Abstract

The experimental trail was performed throughout two successive seasons (2013 and 2014) with the aim of improving growth and quality of three Hibiscus rosa-sinensis cultivars (red flowers “San Diego”, yellow flowers “Butterfly” and orange flower “Peach Schnapps”). Thus, the effect of three types of fertilization with different levels and some combinations with them, Kristalon (NPK 19:19:19 and micro-elements), Diatoms (Algae-fertilizer) and Lithovit (Nano-fertilizer) on the three cultivars were investigated in both seasons. The results emphasized that Hibiscus cv. San Diego was the best cultivar used for its superiority in producing the tallest plant, number of flowers/plant, the heaviest fresh weight of leaves and stem, dry weight of leaves and stem, the heaviest fresh weight of roots, dry weight of roots and total carbohydrates in leaves. Meanwhile Peach Schnapps cv. gave the highest number of leaves/plant, stem diameter and high content of N %, whereas, Butterfly cv. produced the highest number of branches/plant, chlorophyl a, b, carotenoids, P % and K %. On the other side, supplying plants with the combination of Diatoms at 100 cm3 /pot + Kristalon at 2 g/pot gave the highest values in plant hieght, number of branches/plant, stem diameter, number of flowers/plant, the heaviest fresh weight of leaves and stem, dry weight of leaves and stem, the heaviest fresh weight of roots, N %, P %, carotenoids and total carbohydrates in leaves. Meanwhile kristalon at 2 g/plant gave the highest values in number of leaves/plant, chlorophyll a and b. Treating plants with diatoms at 200 cm3 /pot gave the highest values in dry weight of roots. The present study recommends using Lithovit “nano” fertilizer for its highest blade thickness. Moreover, palisade spongy tissues had their highest thickness in plants, in addition to the least changes in case of Hibiscus protein characteristics bands in case of Lithovit “nano” fertilizer. The extract of flowers of H. rosa-sinensis plant species showed better antioxidant potential by DPPH radical scavenging method when compare to IC 50 value . "San Diego" cv. gave the highest antioxidant activity. Among the treatments, the untreated plants and plants which received Lithovit gave highest antioxidant activity.