Quality analysis of seed lots of Handroanthus chrysotrichus (Mart. Ex DC.) Mattos through electrical conductivity tests

Abstract

The lack of knowledge of techniques and difficulties in acquiring seeds and seedlings of native forest species makes it difficult to implement silvicultural experiments despite their great economic importance. The objective of this study was to evaluate the effects of combinations of factors for vigor analysis by means of electric conductivity test, adapting protocols for seeds of Handroanthus chrysotrichus (Mart. Ex DC.) Mattos. Three batches of H. chrysotrichus seeds with different storage periods (lot I = 24 months, lot II = 11 months, III = three weeks) were used in the electrical conductivity test, and different combinations were tested between water volume (40 and 80 mL), seed (20 and 40 seeds), temperature (25 and 35 C °), and seed imbibition time (12 and 24 hours). The germination test was performed with the purpose of validation of the vigor test where the parameters of final germination and germination speed index were evaluated. All the evaluated combinations were efficient for the analysis of the lots, with lots I and II, always presenting higher values of conductivity, and lower percentage of germination and Ivg. Thus, for the electrical conductivity test on H. chrysotrichus seeds, it is recommended to use 20 seeds in a volume of 40 mL during 12 hours of soaking under 35ºC.