Germination of Kielmeyera grandiflora (Wawara) Saddi (Callophyllaceae) seeds in different substrates and temperatures

Abstract

Kielmeyera grandiflora is a forest species from the cerrado, popularly known as pau-santo, with large flowers, pink petals and fruit measuring around 20 cm in length. The objective of this work was to evaluate seed germination, in different substrates and temperatures, under laboratory conditions, to be adopted in the germination test. The seeds were placed to germinate with 4 repetitions of 16 seeds in the substrate between 3 sheets of paper roll + 50 mL of water; in gerbox-type plastic boxes on and between the substrate of 3 sheets of blotting paper + 17 mL of water; between and on the sand substrate (150 g) + 25 mL of water and between and on the vermiculite substrate (20 g) + 50 mL of water, at temperatures of 15, 20, 25, 30 and 35ºC, in germinators BOD type, with 8-hour photo period. The experimental design was completely randomized, in a 5 x 7 factorial scheme (five temperatures and seven substrates). The total percentage and seed germination speed index were evaluated. The results obtained showed high germination at 25ºC, regardless of the substrates tested. The highest germination values were also obtained between sand at 20ºC (91%) and 30ºC (96%) and between vermiculite at 30ºC (99%). For the germination speed index, the highest values were obtained at 20ºC between sand (1.19), at 25ºC between blotting paper (1.99) and between vermiculite (1.93). For the germination test, a temperature of 20ºC is recommended in a substrate between sand; at 25ºC between and on blotting paper, sand, vermiculite and roll paper substrates and at 30ºC between sand and vermiculite.