Effect of Nitrogen (N) Concentration on the Morphology of Teak (Tectona grandis) Seedlings

Abstract

Teak (Tectona grandis) is a timber tree species which is commonly grown by farmers due to its high quality and commercial value. One of nutrient that affects the physiological processes of teak plants is nitrogen (N). This study aims to determine the morphological symptoms of teak seedlings affected by several concentration levels of N and to determine the optimal concentration of N for the best teak seedling growth. This study was conducted using Completely Randomized Design (CRD), which consisted of five treatments, namely minus N nutrient solution (N0), half strength N nutrient solution (N1), full strength N nutrient solution (N2), 1.5 full strength N nutrient solution, 2 full strength N nutrient solution (N4), and aquadest as control (C). Each treatment was replicated 3 times. This research was conducted at the Laboratory of Intensive Silviculture Klebengan from June to November 2016. Parameter observed included height, diameter, nodal distance, and morphological symptoms of leaf. The results showed that variation of N concentration affected teak growth (height, diameter, and nodal distance). They also affected morphology and color of the leaves. Symptoms of N deficiency were the yellowing (chlorosis) and drying of the leaf tips and the presence of yellow spots in the leaf inter veins. N concentration of 995 ppm resulted the best growth, but it caused necrotic in the interveinal area. However this was suspected due to deficiency in Magnesium (Mg). Without N (N0 and Control) caused the lowest seedling growth. The greatest N concentration of 1335 ppm did not give the best growth for teak seedling.