EFFECTS OF MACRONUTRIENTS OMISSION IN NUTRITIONAL SOLUTION ON MILLET GROWTH AND NUTRITION

Abstract

The objective of this research was to evaluate the effect of macronutrients omission on millet, cv. BRS 1501, development and nutrition. The experiment was carried out in a greenhouse, using an aerated nutritional solution. The experimental design was completely randomized, with seven treatments, corresponding to the Hoagland & Arnon's complete solution and the individual omission of N, P, K, Ca, Mg, and S, in three repetitions. Two weeks after sowing plants were transferred to pots (2,5 L) and the treatments applied. Four weeks later, plant height, leaf number, stem diameter, dry matter, and macronutrient contents accumulated on the aerial part of the plants were evaluated. The omissions of N, P, Ca, and K were the most limiting treatments for accumulation of these nutrients and dry matter production of millet. Plants in the complete treatment and under macronutrient omissions presented the following nutrient contents for the aerial part (g kg-1): N 35.5 and 16.1; P 3.3 and 0.4; K 37.4 and 7.2; Ca 4.2 and 0.7; Mg 1.7 and 0.6; and S 0.6 and 0.8, respectively. Besides decreasing its content for the aerial part, the omission of a nutrient also unbalanced other nutrients and, consequently, caused changes associated with the characteristic deficiency symptoms of each nutrient.

KEY-WORDS: Mineral deficiency; symptoms; Pennisetum thiphoideum.