Multivariate characterization and canonical interrelations for the productive performance of open pollinated corn genotypes
Corn is considered one of the most important crops in the world agricultural scenario. In order to improve production, it is crucial to understand and quantify the genetic variation involved in the phenotypic manifestation of this species. We characterized corn genotypes using a multivariate approach and examined canonical interrelations between characters of agronomic importance. The study was carried out in the 2016/2017 crop year in the southernmost state of Brazil, in the northwest region of Rio Grande do Sul. The treatments were composed of six open-pollinated corn genotypes (PL 712, PL 725, PL 796, PL 804 and PL 861). The experimental design was a randomized block with four replications. Analysis of variance revealed a significant difference at 5% of probability by the F test for the attributes plant height, ear insertion height, stem diameter, ear length, number of seed rows per ear, number of seeds per row of ear, thousand seed weight, seed yield, percentage of germination, first germination count, emergency percentage and cold test. Genetic variability analysis showed genotype PL 712 to have superior seed productivity. The physiological quality of the seeds produced was variable among the genotypes, but it followed the trend of superiority for PL 712. Linear associations revealed a tendency for tall stature plants to increase seed yield of open pollinated corn. The most polymorphic characters were plant height and ear insertion, response to cold test, and thousand seed weight. The productivity and seed quality trends that were observed will allow us to plan further research on open pollinated varieties to allow selection and development of superior genotypes for seed productivity and quality in the extreme south of Brazil.