Influence of Plant Age on Nutrient Absorption for Marigold Seedlings

Abstract

Seedlings of 30-, 35, 40-, -45, and 50-day-old marigold (Tagetes erecta Big. `Inca Gold') in 500-ml plastic pots containing a 1 peat: 1 perlite (v/v) medium were treated with several fertilizer levels (N at 20, 50, 80, and 110 mg·liter -1 ); solution nutrient levels in the medium were determined 6 hours later. Older/larger container-grown plants absorbed more N, P, and K from the medium solution than younger/smaller plants. Also, older plants (>40 days) absorbed at least 88% of the solution N regardless of N treatment. Nitrogen absorption, regardless of plant age, increased as N application rates increased. The latter result implies that even though total N absorption increases with plant age/size, nutrient levels in the medium solution for optimal growth and nutrient uptake may be similar regardless of plant size.