Nearly 30 years ago the conditions for culturing immature cotton ovules wer
e established to serve as a working research tool for investigating the phy
siology and biochemistry of fibre development. Not only has this tissue cul
ture method been employed to characterize the biochemistry of plant cell ex
pansion and secondary cell wall synthesis, but ovule cultures have contribu
ted to numerous other aspects of plant cell physiology and development as w
ell. In addition to basic studies on fiber development, cotton ovule cultur
es have been used to examine plant-fungal interactions, to model low temper
ature stress responses, to elucidate the pathways responsible for pigment f
ormation in naturally pigmented fiber and to probe how cytoskeletal element
s regulate cell wall organization. Success in rescuing Gossypium interspeci
fic hybrids was dependent on ovule culture media formulations that could su
pport early embryo development in ovulo. As tissues produced in culture are
analyzed by increasingly more sophisticated techniques there appear to be
some differences between ovule growth in planta and ovule growth in vitro.
Discerning how ovule culture fiber development is different from fiber deve
lopment in field-grown plants can contribute valuable information for crop
improvement. Cotton ovule cultures are an especially attractive model syste
m for studying the effects of gravity on cell elongation, cellulose biosynt
hesis and embryo development and are excellent target for examining transie
nt expression of introduced gene constructs. With only minor modification,
the procedure originally described by C. A. Beasley; and I. P. Ting for gro
wing cotton ovules in vitro will continue to le a useful research tool for
the foreseeable future.