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Somatic embryogenesis of norway spruce (Picea abies (L.) Karst.)
Fischerová, Lucie ; Vágner, Martin (advisor) ; Malá, Jana (referee) ; Salajová, Terézia (referee)
5. CONCLUSIONS . The development of somatic embryos on maturation meďum can be divided at anatomical level into fow developmental stages, differing in the inner struďure: stage of early somatic embryo, cylindricď stage, precotyledonary stageand cotyledonary stage. o The prolonged cultivation of coýledonary errrbryos on maturation medium leads to disintegration of the root cap, connected with starch and phenolic cornpormdsdeposition. o The time course of disctete developmental stagesis affected by PEG 4000; use of 3,75 % PBG speeds up the process of maturation by tvro weeks. Increased level of PEG (7,5%o)leads to the formation of nrpturesin ernbryohypocotyls. The content of non-structural saccharides increases during the cultivation of embryogenic culture on maturation medium due to increasing level of sucrose in developing embryos. The content of hexoses in embryos is low. The addition of 3,75 % PEG 4000 into maturation medium increases the sucrose to hexoses ratio in somatic embryos, the total amotmt of saccharides slightly decreases.7,5 %PEG leadsto hexosesaccumulationin embryos. Insertion of pre-maturation phase (without growth regulators) between proliferation and maturation increases total amount of developed embryos in a majority lines tested. cultivation of embryogenic cultues of rafts with...
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