Effects of nitrogen levels and harvest ferquency on the growth and leaf quality of moringa (Moringa oleifera Lam) in Sudan Savanna of nigeria

Abstract

Field experiment was conducted under irrigation at teaching and research farm of Faculty of Agriculture, Bayero University Kano, during 2011/2012 dry season to investigate the effects of different nitrogen levels and harvest frequency on growth and leaf quality of Moringa (Moringa oleifera (Lam)). The treatments consisted of four levels of nitrogen (0, 50, 100 and 150 kg N ha^-1) and three times of harvest frequency (2, 3, and 4 weeks). These were arranged in a split plot design with the nitrogen levels allocated to the main plots while the harvest frequency allocated to the sub plots and replicated four times. The data collected were subjected to analysis of variance (ANOVA) using GenStat and significant different means were separated using DMRT. The result shows that application of nitrogen significantly (P<0.05) increase plant height, number of leaflets plant^-1, plant stem diameter, number of branches plant^-1, fresh and dry weights plant^-1. Generally, the growth characters assessed gave maximum value with 150 kg N ha^-1 treatment. At first harvest highest protein content of the leaf was also obtained with the higher Nitrogen level (150 kg N ha^-1), highest Magnesium was obtained with 100 kg N ha^-1 while highest quantity of phosphorus and potassium were obtained with 50 kg N ha^-1. The increase in harvest frequency significantly (P<0.05) increased dry leaf quality of Moringa with the highest protein quality obtained from 4 weeks harvest frequency. Nitrogen and harvest frequency interaction was found to be significant (P<0.05) on dry leaf quality of Moringa.

Keywords: Moringa, nitrogen, harvest frequency and leaf quality