Analysis of effects of nitrogen and magnesium fertilization combinations of phenotypic traits of two maize (Zea mays L.) cultivars using multivariate methods

Abstract

The paper presents results of multivariate analysesassessing variation in quantitative traits after the applicationof nitrogen and magnesium rates in cultivation of two types ofmaize (Zea mays L.) cultivars, i.e. ES Palazzo and the stay-greenES Paroli. The purpose of this study was to assess the multivari-ate phenotypic variation of 16 objects which are a combinationof four nitrogen doses, two doses of magnesium and two varie-ties characterized by varying the rate of aging. Observations wereconducted for eight traits: plant height, ear height, ear length, eardiameter, ear volume, the number of plants after emergence, thenumber of plants before harvest, plant loss rates in the vegetationperiod, observed in the course of three years (2009-2011). Sta-tistical analysis of results was performed using the multivariatemethods. Analysis of canonical variables proved to be a reliabletool providing a comprehensive assessment of variation in the ef-fect of urea and magnesium fertilisation combinations on manytraits simultaneously. The most variable treatments were A2B2C2(50 kg N ha-1, 25 kg MgO ha-1 for ES Paroli SG) and A4B2C1(150 kg N ha-1, 25 kg MgO ha-1 for ES Palazzo). The most simi-lar treatments (in terms of eight traits treated jointly) includedA2B2C2 (50 kg N ha-1, 25 kg MgO ha-1 for ES Paroli SG) andA3B2C2 (100 kg N ha-1, 25 kg MgO ha-1 for ES Paroli SG). Ma-halanobis distances between individual treatments in individualyears of observations were positive and correlated statisticallysignificantly.