Use of canonical variate analysis to differentiate onion cultivars by mineralcontent as measured by ICP-AES

摘要

Three onion cultivars viz. Renate, Ailsa Craig and SS1 were characterisedaccording to their mineral content. The concentrations of the macronutrientsphosphorus, potassium, calcium, manganese and sulphur and the micronutrientsiron, boron, manganese, copper and zinc were analysed in freshly harvested andstored onion bulbs using ICP-AES (Inductively coupled plasma-atomic emissionspectroscopy). Onions were treated pre-harvest with additional sulphur (100 kgha−1) and/or calcium (300 kg ha−1) applied in four combinations at the time ofseed drilling, however these treatments did not affect the total concentrationsof sulphur or calcium in the harvested bulbs. The data were subjected tocanonical variate analysis in order to determine the most appropriate variate todiscriminate between cultivars. Two canonical variates were sufficient todifferentiate between the three cultivars, with the first canonical variatedescribing differences in micronutrients between the genotypes and the secondseparating the cultivars by differences in sulphur concentrat