The effect of nitrogen fertilization level on growth, yield and nodulation of Indigofera zollingeriana at early nursery stage

The objective of this study was to determine the effect of nitrogen fertilizer level on growth, dry matter yield and nodulation of Indigofera zollingeriana plant at during the nursery. The experiments were arranged in a complete randomized design consisting of four treatments and four replications. The utilized four levels of the nitrogen fertilizer were 0 (P0), 100 (P1), 150 (P2) and 200 kg N/ha (P3) equivalent to 0, 0.15, 0.23 and 0.30 g N/polybag respectively. The variables in this study included the plant height, stem diameter, number of petioles per plant, length of petiole, number of leaves per plant, root length for each plant and dry matter yield. The results showed that the fertilizer doses increased the plant height, stem diameter, number of leaves per plant, and dry matter yield of leaf, leaf petiole, stem, root and nodule. It could be concluded that nitrogen fertilization was effective in stimulating growth, production and nodulation at early nursery stage, yet higher nitrogen doses (200 Kg N/ha) are ineffective and have inhibitory effects of growth and production. Therefore, high-dose nitrogen fertilizers in legume plants should be avoided because Indigofera zollingeriana is able to fix nitrogen from the atmosphere as in other legumes.