Cellular Forms in Cultivation in Suspension of Bougainvillea glabra Choisy Variety Surprise

Abstract

The objective of this work was to describe the predominant cell forms in the phases of growth kinetics in a suspension culture of the Bougainvillea glabra Choisy variety Surprise. Treatments in suspension with Murashige and Skoog (MS) basal culture medium were supplemented with six different concentrations and combinations of vegetable growth regulator (VGR) of type auxin (2,4-D and NAA) and cytokinin (BAP) (0.2-5.3 mg/L) and a control. Friable callus was obtained from leaf explants ex vitro to in vitro culture in solid MS medium using Phytagel as gelling agent to 2.2 g/L. A portion of callus (1.0 g) was used as cellular inoculum and grown under controlled conditions (50 mL, 120 rpm, 25 °C and luminous intensity of 48 μmol m/s). The best treatment with significant differences (p ≤ 0.05) were with a hormonal relation of 2:1 of BAP and NAA, respectively, with a fresh weight yield ranging from 1.7905 g to 5.8340 g, which represents around 70%. An adaptation phase was observed from day 0 to day 14 on the curve of fresh weight; an exponential phase at day 14 to day 19 and a declination phase at day 21. Cellular forms in the adaptation phase were elongated cells, a few globular and a few with kidney shape. In the exponential phase, these cells formed small aggregates of globular cells. In the death phase, brown, elongated, damaged and fragmented cells were found. Whit this data obtained it is possible to establish the subculture time in fresh medium.