Resumo

MALAVOLTA, E. et al. Studies on the mineral nutrition of the rice plant: XVIII. effects of the deficiencies of macro and micronutrients and of the toxicity of aluminum, chlorine and manganese on morphology, growth, yield, and mineral composition of the varieties IAC -164 and IAC-165 grown in nutrient solution. An. Esc. Super. Agric. Luiz de Queiroz [online]. 1982, vol.39, n.2, pp. 815-850. ISSN 0071-1276.  http://dx.doi.org/10.1590/S0071-12761982000200014.

Rice, varieties IAC-165 and IAC-165, both upland, were grown in nutrient solution (Hoagland's nº 2) complete, with deficiency of N, P, K, Ca, Mg, S, B, Cu and Zn, and with excess of Al, CI, and Mn. Symptoms od feficiency and toxicity were observed according to the treatments. Dry matter production by var. IAC-164 was affected by the treatments in the following order: - N, -K, -P, -Mg, -B, -Ca = -Zn, -S, and -Cu; in the case of var. IAC-165, the sequence was -B, -N, -P, -K, -Mg, -Ca, -Cu, -S, and -Zn. There was no grain yield in treatments -Ca and -B. The toxicity of Al, CI, and Mn significantly decreased dry matter formation; Mn was more detrimental than Al. Variety IAC-164 was more sensitive to the toxic levels of Al and CI. At full tillering the following tissue levels in the freshly mature leaves are considered as adequate, respectivelr the varieties IAC-164 and IAC-165. N - 2.32-2.70%, P - 0.28-0,49, K - 2.83-4,21, Ca - 0.94-0,94, Mg - 0.73-0.88, S - O.13-0.16%.