Abstract
This experiment was held at the nursery of Hort. Res. Inst., ARC, Giza, in 2018 and 2019 seasons to clarify the consequence of fertilization with NPK mixture (2:1:2) at the rates of 2 and 4 g/plant, osmocote slow-release fertilizer at the rates of 10 and 20 g/plant and humic acid (HA) liquid fertilizer at the rates of 10 and 20 cm3/l of water on growth and chemical composition of Foxtail palm cultured in 20-cm-diameter polyethylene bags. NPK mixture and HA fertilizers were applied as a soil drench, five times with one-month interval, while osmocote was incorporated into the soil, once at commencement of the season. The results indicated that means of various vegetative and root growth parameters were significantly increased in response to the different fertilization treatments used in this study over control in most cases of the two seasons. However, the dominance was for both NPK mixture and osmocote treatments, but the upper hand was for the high rates of both (4 g NPK and 10 g osmocote per plant). On the other hand, the least improvement was achieved by HA treatments, especially when applied at a low level (10 cm3/l). A similar effect was also obtained regarding chlorophyll a, b, carotenoids, N, P and K concentrations in the leaves, with few exceptions. Thus, to obtain a picturesque pot plant of Foxtail palm (Wodyetia bifurcata), it is recommended to fertilize with osmocote (the slow-release fertilizer active for 10 months) at 10 g/plant/season as one batch applied at beginning of the season.