EFFECT OF NPK FERTILIZER AND SOME NATURAL EXTRACT TREATMENTS ON THE VEGETATIVE GROWTH AND FLOWERING OF AFRICAN MARIGOLD (TAGETES ERECTA L. VAR. DWARF CHRYSANTHEMUM)

Abstract

A pot experiment was carried out during the two successive seasons of 2017 and 2018 at the Nursery of the Ornamental Plants Research Department, Horticultural Research Institute, Giza, Egypt, to investigate the effect of applying NPK fertilization at the rates of zero and 2 g/pot as a soil drench and natural extracts of seaweed, Moringa oleifera leaves and dry yeast thrice as a foliar application at concentrations of zero, 1 and 2 g/l individually or in combination with NPK fertilizer on vegetative growth and flowering characteristics of African marigold (Tagetes erecta L. var dwarf chrysanthemum). Results revealed that supplying plants with NPK at 2 g/pot in combination with seaweed extract at 2 g/l or applying such extract individually significantly stimulated vegetative growth parameters as well as the rooting parameters. Moreover, seaweed extract promoted some flower characteristics. However, the most effective treatments to achieve the significantly earliest flowering in both seasons was concomitant to plants supplied with NPK at 2 g/pot combined with yeast extract at 2 g/l, followed by those treated with the same extract alone when compared to control.