Psychotria nuda (Cham. & Schltdl.) Wawra: Rooting of stock plants in different phenophases and environments
Psychotria nuda (Cham. & Schltdl.) Wawra (Rubiaceae) is a native species from the Dense Ombrophylous Forest (dense tropical rain forest), typical in the low altitude areas of the forest, with occurrence in the states of Minas Gerais, Rio de Janeiro, São Paulo, Paraná and Santa Catarina. Due to the presence of yellow flowers with red receptacle and anise colored fruits, the plant has an ornamental potential, such as a pharmaceutical potential, thanks to the variety of alkaloids that have already
... been isolated demonstrating structural diversity of its active components. This work aimed to verify the effect on stem cuttings rooting of different collection environments and of different phenophases of Psychotria nuda stock plants at the time of collection, and to verify what is the correlation between variables defined as percentage of rooted cuttings, number of roots per cutting and average length of the three longest roots per each cutting (cm) with permanence of two half leaves and formation of callus. Phenophases are intended as different times of the year in which stock plants presented distinct phenological characteristics. In the two phenophases studied (phenophases 1 and 2) canopy sprouts were collected in Antonina, Paraná state, from two different environments (plain and hillside) of the Dense Ombrophylous Forest (dense tropical rain forest). Cuttings were prepared with 10 to 13 cm length and two halved leaves. After 60 days in a greenhouse, the percentage of cuttings with roots, with callus, alive, dead, the number of roots per cutting and the length of the three longer roots per each rooted cutting were evaluated. The collection environments and the phenophases at the time of collection influenced the percentage of rooting, such that the phenophase 1 and the hillside environment were the conditions that resulted in the best rooting percentage (90%). The permanence of leaves during rooting period helped, in most cases, the formation of adventitious roots. Anticipated formation of callus supported rooting in phenophase 2, while in phenophase 1 the formation of adventitious roots was independent from callus formation.