Application of nitrogen and 2,4-D as growth regulator in corn. I. Dry matter accumulation and grain yield

Abstract

A field trial was conducted with com at the Estação Experimental Agronômica da UFRS, Guaíba-RS, Brazil, to verify the effects of nitrogen and 2,4-D applications on the dry matter accumulation in the different organs of the plant, length of period from silking to physiological maturity of the grains and grain yield. The treatments were two levels of nitrogen (40 and 120 kg N/ha) and four levels of 2,4-D (0,80, 160 and 240 g a.e./ha). Dry matter in the different organs of the plant was determined each six days from silking to 72 days after. The application of 2,4-D did not affect significanty the determinations evaluated. The high level of nitrogen increased dry matter of leaves and husks, cob, grain, grain yield, number of grains per ear and weight of 1,000 grains. The length of period from silking to grain physiological maturity were not affected by 2,4-D and nitrogen applications.