Effect of nitrogen, potassium and media on the growth and flowering of marigold (<i>Tagetes erecta </i> L.)

Abstract

A greenhouse experiment was carried out to evaluate the effect of nitrogen, potassium and media on the growth and flowering of marigold ( Tagetes erecta L.). The experiment was conducted as a 4 x 4 x 2 factorial laid out in Completely Randomized Design (CRD) with five replications. The treatments comprised four rates of nitrogen (0, 50, 100 and 150ppm N), four rates of potassium (0, 50, 100 and 150ppm K) and two media (9:1 ricehull: river sand and 3:2 topsoil : riversand). Topsoil medium produced a higher shoot dry weight and a wider plant canopy than the ricehull medium. In the topsoil medium, at all nitrogen levels, 50ppm K that produced the highest shoot and root dry weight also produced the highest flower diameter. Shoot dry weight, root dry weight and number of flowers were highest at 100ppm K for all nitrogen levels in the ricehull medium. The number of days to 50% flower bud initiation and anthesis was shorter in ricehull medium than topsoil medium. The results showed that with the availability of 150ppm nitrogen in the media, 50ppm K and 100ppm K in topsoil and ricehull media, respectively was sufficient for the production of pot marigold. Keywords : Nitrogen, potassium, growth media, marigold, Tagetes erecta > Agro-Science Vol. 6 (1) 2007: pp. 46-55