Caracterização morfológica e fisiológica das sementes de paricarana (Bowdichia virgilioides Kunth.) e açaí (Euterpe oleracea Mart.)

Abstract

Researches with forest species has increased in recent years due to the benefits each species brings for human use. However, the propagation of these species by seed is a challenge due to a series of factors such as dormancy and drying of recalcitrant seeds, which can affect germination and storage. With this, the objective of this work was to evaluate the physical, physiological and isoenzymatic quality of paricarana and açaí seeds, with the intent of identifying the best seed quality for propagation and storage. For the paricarana species, we obtained seeds from 12 matrices, classified in colors orange and red for determining its quality by means of image analysis and verification of the efficiency of the treatment for overcoming dormancy by immersing the seeds in water at 100 o C for 10 seconds, plus 5 minutes of immersion in hypochlorite at 2%. With the results, we verified that the techniques used for physical and physiological characterization of orange and yellow seeds of the 12 paricarana matrices are efficient. The orange paricarana seeds present better physical and physiological quality. The treatment with water at 100 o C for 10 seconds plus 5 minutes of immersion in hypochlorite at 2% is efficient in overcoming dormancy and disinfecting the seeds of the 12 paricarana matrices. For the açaí seeds, three experiments were conducted: 1 st - evaluation of the storage environment (natural and cold chamber) x storage (zero, 60, 120, and 180 days) x water content (35, 30 and 20%); 2 nd - seed size (large and small) x storage (zero, 60, 120 and 180 days) water content (35, 30 and 20%); and fungicide (with and without) x storage (zero, 60, 120 and 180 days) x water content (35, 30 and 20%). Seed quality was determined by the physical, physiological and isoenzyme tests. With the results obtained, we verified that the açaí seeds with 35% and 30% of moisture have better physiological quality. The best storage environment is the natural. The large açaí seeds with 35% and 30% have better physiological quality and vigor. The drying of the açaí seeds to 20% of water content drastically reduces the physiological quality of the seeds of both sizes. Açaí seeds with 35% and 30% of water content, treated with fungicide have better physiological quality. The fungicide treatment is efficient for the entire storage period for açaí seeds with 30% and 20% of water content, and for seeds with 35% of water content, only up to 60 days. Storage for 180 days does not maintain the physiological quality of açaí seeds.