BIOMETRIC PARAMETERS IN THE CHARACTERIZATION OF EARS IN A COLLECTION OF CORN GENOTYPES

Abstract

The study evaluated morphological parameters and yield elements in corn ears to compare a collection of corn genotypes. The research took place in ARDS Lovrin, Romania. 80 maize genotypes were analyzed, and certain representative parameters were determined: corn ear weight (CEW, kg), corn grain weight (CGW, kg), corn cob weight (CCW, kg). Based on the recorded values, the kernels in corn ears was calculated (KCE, %). Several ratios were also calculated, CEW/CGW, CEW/CCW, and CGW/CCW. The data series showed normal distribution and statistical confidence. Very strong positive correlation was recorded between CGW and CEW (r = 0.963), and between the ratios CGW/CCW and CEW/CCW (r = 0.996). Very strong negative correlation was registered between the ratio CEW/CGW and KCE(%), r = -0.992. According to PCA, PC1 explained 69.055% of variance, and PC2 explained 29.108% of variance. The close correlation of the Lv_47 hybrid with the KCE parameter (%) was observed. According to the cluster analysis, the dendrogram for the classification of genotypes based on similarity, in relation to the KCE parameter resulted (Coph.corr. – 0.813). The variation of the KCE parameter (%) in relation to the CEW, CGW, and CCW parameters was analyzed by regression analysis. Mathematical models described the variation of KCE in relation to the considered morphological parameters, under statistical safety conditions (R2 = 0.999 in relation to CEW and CGW; R2 = 0.757 in relation to CEW and CCW; R2 = 0.835 in relation to CGW and CCW; p <0.001 for all cases). Graphical models (3D, isoquants) represented the KCE variation (%) in relation to the considered morphological parameters. The divergent influence was recorded in the case of the CGW and CCW parameters on the KCE distribution.