The impact of genotype, ploidy and environmental factors on morphological and productive traits of maize

Maize is an essential crop for global food security, providing vital nutrients to billions of people. Its adaptation to climate challenges requires the development of productive and resilient varieties using both conventional and molecular breeding methods. Polyploidy significantly contributes to genetic diversity, with effects such as increasing plant organ size, reducing the impact of harmful mutations, and enhancing heterosis. The aim of this research was to evaluate the morphological and productive characteristics of diploid and tetraploid maize lines under polyfactorial experimental conditions. The study was conducted during the 2023-2024 period on the experimental field of the Faculty of Agricultural, Forestry, and Environmental Sciences at the Technical University of Moldova, on a typical chernozem soil under irrigated conditions. The biological material included three maize lines at both diploid and tetraploid levels. The analyzed parameters were plant height, ear insertion height, leaf size, panicle length, number of branches, and yield. The data obtained were statistically analyzed using the Fisher polyfactorial test. The factors investigated were year of research, ploidy, genotype, and replication. The experimental results showed that genotype and ploidy are the main determinants of morphological and agronomic trait variation, significantly influencing (p less than 0.05) plant height, leaf size, and panicle architecture. Environmental factors, especially the year of the experiment, had a variable impact, mainly affecting leaf and panicle size, but with a limited effect on yield. The interactions between genotype, ploidy, and the year of the experiment highlight the complexity of these influences on plant development. Their significance suggests that breeding strategies should consider optimal genotype-ploidy combinations to obtain stable and high-yielding varieties.