Fiziološki i biohemijski aspekti regeneracije košutice (Fritillaria meleagris L.) in vitro
Physiological and biochemical aspects of regeneration snake's head fritillary (Fritillaria meleargis L.) in vitro
Abstract:
We have investigated in vitro regeneration of snake’head fritillary (Fritillaria
meleagris L.), a perennial bulbous geophyte. The induction of morphogenesis in vitro of
snake’head fritillary was achieved in mature zygotic embryo culture, scale segment and leaf
base culture of in vitro formed bulbs. Plant regeneration via somatic embryogenesis and
organogenesis was obtained in mature zygotic embryo culture on a growth regulator-free
medium or on medium supplemented with TDZ. The induction of morphogenesis in vitro
was achieved in scale segment culture of the in vitro formed bulbs on media supplemented
with 2,4-D or TDZ, grown either on light or in darkness, with more efficient regeneration
on media supplementned with TDZ. Somatic embryogenesis was induced in leaf base
culture of the in vitro formed plants on media with 2,4-D, KIN or 2,4-D and KIN.
Anatomical studies revealed that the somatic embryogenesis was direct, with somatic
embryos of multicellular origin formed from epidermal and subepidermal leaf base cells .
The effect of low temperature (4 and 15 °C), higher concentration of sucrose in the
nutritional media and GA3 pretreatment on growth, differentiation and dormancy breaking
of the in vitro formed bulbs was investigated. It was shown that pre-cultivation of the in
vitro regenerated bulbs at lower temperatures and higher concentration of sucrose in the
nutrition media (4,5 %) have stimulatory effect on growth and multiplication of the bulbs.
Also, GA3 pretretment followed by cultivation at low temperature (4 °C) had a stimulatory
effect on multiplication and germination of the bulbs. Cultivation at low temperature breaks
dormancy of the bulbs and causees changes in the sugar content (sucrose, glucose and
fructose), photosinthetic pigments and poliols. Activity of antioxidative enzymes (SOD,
CAT, GR i POX) during dormancy breaking was investigated. It was shown that these
enyzmes are actively involved in dormancy breaking of the in vitro formed bulbs, and in
the process of acclimatization of the bulbs to ex vitro conditions. Antioxidative enzymes
were active during the induction of morphogenesis in vitro in bulb segment culture and
their activity depended on the nutritional media and the pretreatment to which the bulbs
were exposed. During morphogenesis in vitro in the scale segment culture of snake’s head
fritillary, up to 6 esterase isoforms have been detected, depending on the pretreatment and
media composition. The content of arabinogalactan proteins (AGPs) in explants during the
induction of morphogenesis in vitro in leaf base and scale segment cultures at media
supplemented either with 2,4-D and KIN or with TDZ was determined. Concentration of
AGPs increased after seven days of cultivation of explants on media with growth regulators
in the leaf base culture and 21 days in the scale segment culture. In the leaf base culture,
concentration of AGPs in explants was higher on a medium with 2,4-D and KIN than on a
medium with TDZ. The AGP profile obtained by crossed electroforesis reveiled the
presence of one AGP type during induction of morphogenesis in vitro of F. meleagris.
Keywords:
Fritillaria meleagris; Morphogenesis in vitro; Bulb dormancy; Organogenesis; Oxidative stress; Somatic embryogenesis; Antioxidative enzymes; Esterases; Arabinogalactan proteinsSource:
University of Belgrade, Faculty of Biology, 2012, 1-176URI
http://eteze.bg.ac.rs/application/showtheses?thesesId=44https://fedorabg.bg.ac.rs/fedora/get/o:2441/bdef:Content/download
http://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=41534735
http://nardus.mpn.gov.rs/123456789/2032
https://radar.ibiss.bg.ac.rs/handle/123456789/2371