YIELD AND YIELD ATTRIBUTES OF ONION (Allium cepa L.) AS INFUENCED BY NITROGEN FERTILIZER RATES AND PLANT POPULATION UNDER IRRIGATION.

Author(s): Issa, O. M., Hussaini, Y. and Ibrahim. U.
Volume/Issue: Volume 2 , Issue 1 (2022)

ABSTRACT:

Field trials were conducted during 2019/2020 dry season, at the Research farm of the Institute for Agricultural Research (IAR), Ahmadu Bello University, Zaria, Samaru (11º11’N, 07º38’ E) in the Northern Guinea Savanna zone of Nigeria and at the Irrigation Research Station (IRS), Kadawa (11°39ʹN, 08°02ʹE, 500 M above the sea level) in the Sudan Savanna ecological zone of Nigeria to study the yield and yield attributes of onion (Allium cepa L.) as influenced by nitrogen fertilizer rates and plant population under irrigation. Treatments consisted of a factorial combination of five rates of nitrogen (0, 40, 80, 120 and 160 kg N ha-1) and four levels of plant population (160,000; 250,000; 444,444 and 1,000,000 plants ha-1), laid out in a Randomized Complete Block Design (RCBD) with three replications. Bulb diameter, bulb fresh weight, bulb dry weight, and total bulb yield were higher at 120 kg N ha-1 at both locations, while plant population of 160,000 stands recorded the highest means values of the studied parameters except the total bulb yield which was significantly higher at 444,444 plants ha-1. Based on the obtained results, application of nitrogen at 120 kg N ha-1 combined with 444,444 plants ha-1 produced the maximum yield of onion bulb. However, for wider bulb and highest weight, nitrogen at 120 kg N ha-1 with 160,000 plants ha-1 could be suggested under irrigation.

KEYWORDS:

Nitrogen, Plant Population, Onion, Irrigation.