ASSESSMENT OF NUCLEAR DNA CONTENTS VARIATION AND THEIR RELATIONSHIP WITH FLOWERING IN CORN GENOTYPES

Genome size variations are very helpful to provide an understanding of the diversification, evolution and ploidy screening of germplasm and investigate the aneuploidy, cell cycle kinetics, and reproductive pathways for the plants. It is observed that variation in the DNA content has a direct effect on the phenotype of a plant. Flowering time is considered one of the critical adaptation parameters for maize (Zea mays L.), and this study aimed to investigate the DNA content and its relationship with the flowering time in this crop. A total of 19 inbred lines and three hybrids adapted to temperate and tropical regions with early, late and very late flowering were used as plant material. Their DNA content was determined using flow cytometry, and Vicia sativa as standard for the comparison of DNA content. The DNA content of the studied material of corn ranged from 5.508 pg to 6.285 pg, with an average value of 5.817 pg. The Highest DNA content was determined in the Tzi8 inbred line belonging to a group of very late flowering. A highly significant and positive correlation was found between DNA content and flowering time, which was confirmed with a regression analysis. The results of the study revealed that increasing the DNA content resulted in delayed flowering, and inbred lines adapted to tropical regions had a higher DNA content.