Open AccessArtificial light and growth regulators on the in vitro etiolation of Cattleya labiata
Author(s) -
Antonio Anderson de Jesus Rodrigues,
Emanuele Santos,
Roberto Jun Takane,
A. C. P. P. de Carvalho
Publication year - 2017
Publication title -
ciência agronômica/revista ciência agronômica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.424
H-Index - 26
eISSN - 1806-6690
pISSN - 0045-6888
DOI - 10.5935/1806-6690.20170034
Subject(s) - etiolation , shoot , seedling , photoperiodism , biology , micropropagation , botany , dry weight , horticulture , darkness , hypocotyl , in vitro , tissue culture , biochemistry , enzyme
The technique of etiolation is widely used in the micropropagation of various plant species. The aim of this study was to evaluate growth and development in shoots of Cattleya labiata grown in vitro, as a function of growth regulators and the presence and absence of light. Stem segments, approximately ± 1.0 cm in height, were inoculated in test tubes containing 15.0 mL of MS culture medium supplemented with different concentrations of BAP (0.0, 2.0 and 4.0 mg L-1) and NAA (0.0, 1.0 and 2.0 mg L-1), and in different growth environments (growth room, darkness and a photoperiod of 16 hours) in a completely randomised design. At 150 days, the following were evaluated: a) number of etiolated shoots; b) number of nodes per etiolated shoot; c) length of stem segment (cm); d) number of roots; and e) total seedling dry weight (g). The highest mean values were achieved with the use of 4.0 mg L-1 BAP and 1.0 mg L-1 NAA for the number of etiolated shoots, and 2.0 mg L-1 NAA for the number of nodes per etiolated shoot in the absence of light. The length of stem segment was greater in the absence of light; in contrast, the number of roots and the total seedling dry weight were greater in a bright environment, irrespective of the growth regulator added to the culture medium. The etiolation of stem segments is a viable technique, as it provides features that are advantageous in the in vitro multiplication stage of the species