Emergência e vigor de Handroanthus impetiginosus (Mart. ex DC.) Mattos e Tabebuia aurea (Silva Manso) Benth. & Hook.f ex S.Moore em função de diferentes tempos de imersão em água.

Abstract

Considering the strategies for recover degraded areas and the need for studies related to the plant production technology, the objective of this research was to assess the influence of different times of water immersion on the emergence and vigor of seedlings of Handroanthus impetiginosus (Mart. Ex DC.) Mattos and Tabebuia aurea (Silva Manso) Benth. & Hook.f. ex S.Moore. The seeds of the species were submitted to 11 treatments each: Control (T1), periods of immersion in water for 6, 12, 18, 24, 30, 36, 42, 48, 54 and 60 h (T2, T3, T4, T5, T6, T7, T8, T9, T10 and T11, respectively). Four replicates of 25 seeds were used in each treatment. emergence (%) and emergency speed index (ESI) were evaluated 30 days after sowing and were also analyzed: seedling length, diameter, fresh mass and dry mass. The data were subjected to analysis of variance and the means were compared by the Tukey test. In relation to H. impetiginosus, the greatest emergence was found in T7 (90%) and T5 (89%), the highest ESI in T1 (2.61), the largest seedling length and diameter was found in T3, with 11.81 cm and 2.01 mm, respectively, the largest fresh mass was recorded in T7 (0.4518 g) and dry mass in T2 (0.1153 g). Related to T. aurea, there was no significant effect of treatments in the emergency and ESI, the largest seedling length occurred in T9 (18.5 cm), the most representative diameter occurred in T2 (2.34 mm), the largest quantity of fresh mass occurred in T7 (1.2786 g), whereas T9 expressed the highest dry mass value, with 0.3678 g. Therefore, soaking for 12 h (T3) is recommended for H. impetiginosus and 48 h (T9) for T. aurea, in order to obtain more vigorous seedlings of the species.