Methods used at West of Scotland Agricultural College for analyses of loamless composts and recommended levels for tomatoes grown under glass
1980
Wilson, G.C.S. (West of Scotland Agricultural Coll., Auchincruive, Scotland (UK). Chemistry Div.)
Analyses of loamless composts are carried out on three extracts at a 1:2 volume to volume, sample - extractant ratio - (1) distilled water; (2) saturated calcium sulphate; (3) m - ammonium acetate. pH and conductivity are determined on the water extract; nitrogen, phosphate and potash are determined on the filtered calcium sulphate extract and calcium and magnesium on the filtered ammonium acetate extract. The recommended levels of nutrients for tomatoes grown in a peat substrate are: nitrogen 50-100 ppm; phosphate 30-50 ppm (13-22 ppm P); potash 350-450 ppm (290-374 ppm K); calcium 1000 ppm; magnesium 200 ppm calcium/magnesium ratio 5:1; pH 5.5-6.0; pC 3.0-2.9 (conductivity 1000-1300 micro-mhos, 10-13CF)
Mostrar más [+] Menos [-]Información bibliográfica
Este registro bibliográfico ha sido proporcionado por European Union
