142 • Impacts of Applied Genetics — Micro-Organisms, Plants, and Animals 
Photo credits: Flow Laboratories 
Transfer of plantlets grown on agar to soil 
cies basis. However, several conimereial uses ol' 
tissue culture already exist. (See table 2(t.) 
Storage of Germplasm.— lissue culture 
can be used in the long-term storagtt of special- 
ized germplasm, which in\ol\(ts tret'zing c(*lls 
and types of shoots. The culturt? pro\ idtts stable 
genetic material, reduces storage? space, and 
decreases maintenance costs. 
Carrot tissues ha\e been frozen in litiuid ni- 
trogen, thawed 2 years later, and [(‘generated 
into normal plants. Ibis techni(|ue has also 
proved successful with morning glories, syca- 
mores, potatoes, and carnations. Cc’nerally. the 
technique is most useful for plant material that 
is vegetatively propagated, although if it can h(> 
generally applied it could become important for 
other agriculturally imj)oi’tant crops. 
Production of Phaniiacciilicals and 
Other Chemicals From l*Ianl Cells.— be- 
cause plant cells in culture? are similai- to micro- 
organisms in fermentation systems, they can he 
engineered to work as "factories " to produce 
First stage in plant tissue culturing; inoculation 
of plant tissue 
list of some plants propagated through tissue 
culture.) 
Each of the four stages of the complete 
cycle— establishment in culture, organogenesis, 
plantlet amplification, and reestablishment in 
soil— requires precise biological environments 
that have to be determined on a species-by-spe- 
Shows the gradual development of the plant tissue 
on an agar medium 
