Abstract

A field trial was established in 2015 at the Research Farm of the Institute for Agricultural Research, Ahmadu Bello University, Samaru, Zaria (11011’N; 7038’ E and 686 m above sea level). The trial was maintained and data were subsequently collected from the crop in 2016 and 2017. The treatments consisted of four nitrogen rates (0, 50, 100 and 150 N kg/ha) and three intra-row spacings (20, 30 and 40 cm). Factorial combinations of the treatment were laid out in a randomized complete block design and replicated three times. The results showed that in 2015 application of 150 kg N/ha resulted in significantly taller plants, thicker stems, higher leaf nitrogen content and uptake and higher fresh leaf yield compared with 50 kg N/ha and the control. Number of leaves per plant was not significantly affected by nitrogen application. Similarly, the effect of intrarow spacing on plant height, stem diameter and number of leaves was not significant. However, N uptake and leaf fresh yield were significantly increased by spacing plants at 30 cm compared with 20 cm, while 20 cm resulted in significantly higher nitrogen content in leaves compared with 30 cm. Application of 100 and 150 kg N/ha was comparable statistically and higher than 50 kg N/ha and the control which were significantly at par in fruit yield and number of fruits per plant. Fresh leaf yield, fruit and seed yields were significantly increased by 20 cm compared with other spacings. Number of fruits/plant and number seeds per fruit were maximized by 30 cm in 2017. Application of N at 150 kg/ha and intra-row spacing of 20 cm were, therefore, recommended for maximum yield of moringa leaves, fruits and seeds.