Karyomorphological and Morphometric Studies of Ploidy Levels in Some Wheat (Triticum aestivum L.) Genotypes

Karyomorphological Studies of Wheat

Abstract

Karyomorphological and morphometric investigations of different ploidy levels of 14 genotypes of Triticum aestivum L. and one genotype of Triticum durum Desf. showed that, total chromosomal length (TCL) varied between genotypes. The highest value (56.21 mm) was recorded with mean chromosomal length of 8.03 ± 0.81 mm, while the lowest value of TCL (31.65 mm) was found with mean chromosomal length (MCL) of 4.52 ± 0.41 mm. Simple Pearson correlation coefficient (r) between TCL and MCL was the highest (r = 1.0 and P = 0.000). While the correlation coefficients between mean arm ratio (MAR) and parameters: total form (TF), intrachromosomal asymmetry index (A1) and m (karyotype; metacentric region chromosome) as well as the coefficients between TF and m and between A1 and m were the only significant (P<0.01) ones. Intrachromosomal asymmetry had a significant (P = 0.000) effect of total form percent than interchomosomal index. TCL and MCL were the most important karyological features influencing the principal component analysis and had 81.7 % variation, while in combination with MAR revealed 94% variation. Cluster dendrogram revealed close association and adjacent phylogenetic relatedness of tri- and hexaploid and also tetra- and hexaploid genotypes.