Influência de micronutrientes em combinação com macronutrientes no crescimento, produção e absorção de nutrientes na cultura do arroz (Oryza sativa L.) irrigado.

Abstract

The objective of this work was to study the influence of two doses of macronutrients (NPK) in combination with each of the micronutrients (Zn, Cu, Mo, B and Mn), in order to obtain knowledge about the absorption of macronutrients (NPK) , growth and yield of irrigated rice (Oryza sativa L.). The work was developed under greenhouse conditions during the period from March to August 1981, using the "IR-8 Mejorada" rice cultivar and a clayey alluvial soil from the Irrigated Perimeter of São Gonçalo-Pb. , (Sector of the EMEPA Experimental Station). The factorial scheme 2 (5x2 + 1) was adopted in a completely randomized with three replicates. The treatments consisted of two levels of macronutrients (NPK), 5 micronutrients (Zn, Cu, Mo, B and Mn) each in two levels plus the control. The doses of macronutrients were equivalent to 250-120-120 and 500-240-240 kg / ha of NPK, respectively, while the micronutrients were applied at the levels of 5-5-1,5-2-5 and 25- 25-7.5-10-25 kg / ha Zn, Cu, Mo, B and Mn, respectively, plus one control corresponding to each dose of NPK. The results showed that the micronutrients significantly influenced the percentage of full grains / panicle, grain yield and N, P and K grains. There was no significant effect of these elements on the parameters: plant height, tillering, foliar area, number of panicles, weight of 100 grains and dry matter weight of shoot and root. As for the macronutrient doses, NPK 2 content was observed in N, P and K content in grains, plant height, leaf area, number of panicles, percentage of full grains / panicle, grain yield, dry matter weight of the aerial part and root. No influence of these elements was observed on tillering and weight of 100 grains.