- ORCHID BIOTECHNOLOGY 181
huegelii,Cyanicula gemmata,Diuris magnifica,Elythranthera bruno-
nis,Ericksonella saccharata,Eriochilus dilatatus,Microtis media,Phe-
ladenia deformis,Spiculaea ciliata,andThelymitra benthamiana.Pro-
tocols forin vitroseed germination of severalCypripediumspecies have
also been reported by Zeng et al. (2014).In vitroseed germination of
Spathoglottis plicatahas been investigated and germinated seeds were
used forin vitroregeneration systems, providing a fast and suitable pro-
tocol for the species (Stella et al. 2015). Teixeira da Silva et al. (2015)
provides a thorough review of studies involving asymbioticin vitroger-
mination for severalDendrobiumorchids. A number of techniques and
applications ofin vitroorchid seed germination are described by Kauth
et al. (2008b).
In vitroseed germination continues to be a necessary technology for
orchid breeders, who rely on this technique for the development of
new hybrids for the market. New hybrids using this technology have
received awards and recognition during special events, such as the
World Orchid Conference, held every 3 years in different countries
around the world.
C. Micropropagation
Micropropagation of orchids has allowed the rapid, large-scale multipli-
cation of new selections and hybrids, revolutionizing the orchid indus-
try.In vitroclonal propagated orchids are genetically identical and can
be produced year round (Chugh et al. 2009). In addition,in vitrocul-
ture allowed the production of pathogen-free orchids, germplasm stor-
age, and is indispensable to breeding and genetic improvement pro-
grams (Thorpe 2012). A number of protocols have been developed for
the micropropagation of orchids (Griesbach 1986; Jones and Tisserat
1990; Arditti and Ernst 1993; Kyte and Kleyn 1996; Pierik 1997; Tis-
serat and Jones 1999; Chugh et al. 2009; Neumann et al. 2009; Alam
et al. 2010; Khoddamzadeh et al. 2011; Paek et al. 2011; Panwar et al.
2012; Divakaran et al. 2015; Teixeira da Silva et al. 2015; Rodrigues et al.
2015; Zeng et al. 2015). Such methods include the use of shoot tips, leaf
segments, inflorescence axis and flower buds, and rhizome and root seg-
ments (Chugh et al. 2009). Some of the methods of micropropagation
reported include the use of leaf segments through direct organogenesis
(Chen and Chang 2004b; Shiau et al. 2005), which eventually developed
into plantlets, PLBs regenerated from shoot tips, root tips and stem seg-
ments through direct embryogenesis (Chen and Chang 2000a, 2000b;
Zhang and Fang 2005) and culture systems established using transverse
thin cell layers (TCL) of stem nodes (Zhao et al. 2008; Chugh et al. 2009).