Pot growing Media Amendment with Calcium Cyanamide and Weed Control Relationships
M. Leytur
Faculty of Agronomy, University of Buenos Aires, Avenida San Martín 4453 (C1417DSE), Buenos Aires, Argentina
A. C. Duarte Vera
Faculty of Agronomy, University of Buenos Aires, Avenida San Martín 4453 (C1417DSE), Buenos Aires, Argentina and IFEVA-CONICET, San Martín Av. 4453 (C1417DSE), Buenos Aires, Argentina
A. Sala
Evonik Degussa Argentina S.A., Argentina
B. Giardina
Faculty of Agronomy, University of Buenos Aires, Avenida San Martín 4453 (C1417DSE), Buenos Aires, Argentina
A. Di Benedetto *
Faculty of Agronomy, University of Buenos Aires, Avenida San Martín 4453 (C1417DSE), Buenos Aires, Argentina and Faculty of Agricultural Sciences, National University of Mar del Plata, Route 226, km. 73.5 (B7620ZAA), Balcarce, Province of Buenos Aires, Argentina
*Author to whom correspondence should be addressed.
Abstract
The aim of this research was to characterize the effect of a pre-transplant calcium cyanamide fertilization on weed control in the potted bedding ornamental plant Impatiens wallerana and to describe the physiological mechanisms involved. The positive effect of a calcium cyanamide amendment included both ammonium toxicity on weed seed germination and a decrease of weed rates growth such as relative leaf expansion rate (RLAE) and relative growth rate (RGR). Data showed RGR-NAR (net assimilation rate), RLAE-RGR, RLAE-NAR and RGR-root dry weight relationships, which would explain ammonium toxicity to roots and weed growth responses. These effects probably could be explained by a change in hormonal root synthesis. Our results showed that a pre-transplant calcium cyanamide amendment combining with a transplant routine optimize both I. wallerana growth and weed control.
Keywords: Growing media, ammonium toxicity, transplants, weeds