Use of Nutrient Balance for Improving Fruit Yield and Quality of Tangerine (<I>Citrus reticulata</I> Blanco) cv. Sainampueng: III. Effect of Fruit Development on Leaf Nutrient Concentration

Abstract

The experiment aimed to study the effect of fruit development on leaf nutrient concentration of tangerine (Citrus reticulata Blanco) cv. Sainampueng. Leaves were sampled from the farmer’s orchard in Fang district of Chiang Mai province. For taking leaf sample, the four treatments were arranged in completely randomized design, consisted of taking time in 1) non bearing twig, 2) bearing twig with two–month-old fruits 3) bearing twig with five–month-old fruits and 4) bearing twig with eight–month-old fruits. Subsequently, the concentrations of N, P, K, Ca, Mg, Fe, Mn, Cu, Zn and B of sampled leaves were analyzed. The results indicated that concentration of N, P, K, Mg, Cu and B were decreased in bearing twigs with 2- and 5–month-old fruits but its were increased in bearing twigs with 8–month-old fruits. But Ca was opposite. The concentration of Fe, Mn and Zn were increased in bearing twigs with 2–month-old fruits but its were decreased in bearing twigs with 5- and 8–month-old fruits.