Factor analysis for yield contributing traits in maize (Zea mays L.)

Data collected on 17 traits from 144 inbred lines derived using 4 different base populations of unknown pedigree were subjected to factor analysis. Sixteen factors were extracted using principal component analysis as extraction method. Out of 16, only 5 factors had eigen value greater than one and these factors alone accounted for 78.3% of total variance. The loadings of each variable onto each factor was analysed from the rotated factor matrix obtained through varimax rotation. First factor accounted for 22.93% of the total variation and showed significant associations of traits related to duration namely days to 50% tasseling, days to 50% silking, anthesis silking interval and days to maturity. Second factor with 19.22% of total variation had higher loadings of plant height and ear height which are the important growth traits in maize. Factor 3 with a contribution of 17.91% to total variation was found to be significantly associated with the important yield traits viz. cob yield/plant, grain yield/plant and ear girth. Factor 4 (9.99% variance) and factor 5 (8.33% variance) were loaded mainly with hundred seed weight and grain setting length respectively.