The method for the fast estimation of a plant nitrogen status: Possibility to use SPAD chlorophyll meter

Abstract

The main objective of this study was to test the possibility to use the SPAD-meter as an appropriate tool for the fast estimation of a nitrogen status in both, Italian ryegrass (Lolium italicum L.) and catch weed (Galium aparine L.) that occurred as a predominate Italian ryegrass weed species. The measurements of the SPAD-units were conducted four times (from the stage of the Italian ryegrass stem elongation to the seed ripening stage, in two-week intervals) during the growing season, followed by the chemical analyses of nitrogen in the same leaf material. The high correlation between the leaf nitrogen content (expressed as a percentage per dry weight basis) and SPAD-units, were found in all treatments (varying from 0.75 lt Rxy≤0.90 to 0.90 lt Rxy≤0.99). Obtained results showed that method based upon using a SPAD chlorophyll meter was suitable for a quick estimation of the nitrogen status in plants.

U ovom radu ispitivana je mogućnost korišćenja ručnog prenosnog SPAD (Spectral Plant Analysis Diagnostic) hlorofilmetra (SPAD-502) za brzo merenje sadržaja azota u usevu Lolium italicum L. i korovskoj vrsti Galium aparine L. Na osnovu korelacione analize utvrđeno je da postoji jaka do vrlo jaka pozitivna zavisnost (od 0,75 lt Rxy≤0,90 do 0,90 lt Rxy≤0,99) između sadržaja azota u biljkama određenog standardnom hemijskom (Kjeldahlovom) metodom i procene njegovog sadržaja dobijenog na osnovu SPAD očitavanja. Dobijeni rezultati ukazuju da je metoda zasnovana na korišćenju SPAD hlorofilmetra podesna za brzu procenu obezbeđenosti biljaka azotom.