REIS, L. G. L.; REIS, Luiz Gonzaga Luna.
Resumo:
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.