Qualidade fisiológica de sementes e desenvolvimento inicial de plântulas de açaizeiro em função de embalagens e tempos de armazenamento

Abstract

The cultivation of the açaí palm (Euterpe oleracea) aiming for the production of high agronomic standard seedlings is predominantly done through seeds, which are characterized as recalcitrant, which can be a difficulty for seedling production. The study aimed to evaluate the effect of packaging and storage times on the physiological quality of açaí seeds. The experiment was conducted from June 2022 to February 2023 at the Seed and Seedling Technology Laboratory, at the State University of West Paraná, Campus Marechal Cândido Rondon. Samples from a batch of seeds obtained in the Municipality of Santa Helena, Paraná, were stored at 20 °C ±2 and subjected to vigor tests every 20 days. The experimental design adopted was completely randomized (CRD) in a 4x5 factorial scheme, with four replications and 80 experimental plots. The factors were: four types of packaging (plastic bag, kraft paper bag, bleached cloth bag, and raffia bag) and five storage times (0, 20, 40, 60, and 80 days), totaling 20 treatments. There was a decrease in seed moisture content over the storage time and variations in moisture content due to the packaging. Seeds stored in plastic bags showed the lowest moisture loss over the storage time. There was a significant difference in electrical conductivity of seeds stored for 40 days in the bleached cloth bag packaging, with the highest value (12,03 µS cm-1 g-1)). With superiority, 100 and 50% of the embryonic axes of the stored seeds, respectively for 0 and 20 days in plastic bags, presented the uniformly colored distal portion by the tetrazolium test. Seeds stored in plastic packaging also showed superior results in the first count, emergency speed index, and average germination percentage. Additionally, this same condition resulted in the formation of a higher number of seedlings with a pair of leaves, seedlings with a higher number of roots, larger seedlings, and higher levels of dry mass, compared to the other storage conditions, at the end of the count. The plastic packaging was the most suitable for storing acai seeds under controlled environmental conditions.