|
|
The effect of autoregulated ipt gene expression, exogenous cytokinins and nitrate on cytokinin metabolism and leaf senescence
Sýkorová, Blanka ; Kamínek, Miroslav (advisor) ; Griga, Miroslav (referee) ; Procházka, Stanislav (referee)
coNcLUsroNs l. ttre iptexpressionundeÍthesenescence-specificSÁGí2 promoterresultedin de|ayof |eaÍ senescence,increaseof contentof bioactivecytokininsand nitratereductaseactivityin leavesas wellas to enhancementof nitrateinfluxin plantsgrownunderlimitedN supply. However,the SAG12::iptplantsdid not differfromWT plantsin grainyield components includingthe numberof grainsand grainweight.Resultssuggestthatdelayof leafsenesce of wheat plantsalso delays translocationof nutrientsand metabolitesfrom leaves to developinggrainsafteranthesisand in this way interfereswiththe reproductivestrategy wheatas strictlymonocarpicplantwhichis basedon a programmedfast translocationof metabolitesand nutrientsfrom senescingleavesto the reproductivesinks shortlyafter anthesis. ll. Respondingto the mostlyvaguestatementsthatthe physiologicaleffectsof cytokininsare dependenton plantgenotypeandaffectedbyvariousinternalfactorswe testedtheefficiency of andaromatic(3OHBAR)andan isoprenoid (t-ZR)cytokininon retentionof chlorophyllin detachedoat and wheatleafapices.The efficiencyof thetwocytokininsin preservationof chlorophyllwas differentin the oat and wheatdependingon local or whole adaxialleaf surfacecytokininapplication.The oat and wheatleafpiecesdifferedin the ratesof uptake and the dynamicsof ["H]t-ZRand [JH]3OHBARtranslocationwhichwas...
|
|
|
The effect of autoregulated ipt gene expression, exogenous cytokinins and nitrate on cytokinin metabolism and leaf senescence
Sýkorová, Blanka ; Kamínek, Miroslav (advisor) ; Griga, Miroslav (referee) ; Procházka, Stanislav (referee)
coNcLUsroNs l. ttre iptexpressionundeÍthesenescence-specificSÁGí2 promoterresultedin de|ayof |eaÍ senescence,increaseof contentof bioactivecytokininsand nitratereductaseactivityin leavesas wellas to enhancementof nitrateinfluxin plantsgrownunderlimitedN supply. However,the SAG12::iptplantsdid not differfromWT plantsin grainyield components includingthe numberof grainsand grainweight.Resultssuggestthatdelayof leafsenesce of wheat plantsalso delays translocationof nutrientsand metabolitesfrom leaves to developinggrainsafteranthesisand in this way interfereswiththe reproductivestrategy wheatas strictlymonocarpicplantwhichis basedon a programmedfast translocationof metabolitesand nutrientsfrom senescingleavesto the reproductivesinks shortlyafter anthesis. ll. Respondingto the mostlyvaguestatementsthatthe physiologicaleffectsof cytokininsare dependenton plantgenotypeandaffectedbyvariousinternalfactorswe testedtheefficiency of andaromatic(3OHBAR)andan isoprenoid (t-ZR)cytokininon retentionof chlorophyllin detachedoat and wheatleafapices.The efficiencyof thetwocytokininsin preservationof chlorophyllwas differentin the oat and wheatdependingon local or whole adaxialleaf surfacecytokininapplication.The oat and wheatleafpiecesdifferedin the ratesof uptake and the dynamicsof ["H]t-ZRand [JH]3OHBARtranslocationwhichwas...
|
|
|
Relationships between vernalization, frost tolerance and expression f dehydrins in barley (Hordeum vulgare L.)
Kosová, Klára ; Prášil, Ilja (advisor) ; Kamínek, Miroslav (referee) ; Chloupek, Oldřich (referee)
.l Rukopis I The relationshipbetweenvernalization-and photoperiodicallv-regulatedsenesand the developmentof frost tolerancein wheat and barlev Kosová,K., Prášil,I.T.'Vítámvás,P. BiologiaPlantarum52(): 601-615,2008 Abstract The review summarizes the level of current knowledge of impacts of vernalization and photoperiodon the induction and maintenanceof frost tolerance(FrT) in wheat and barley. The phenomenonof vernalizationis briefly describedandthe major vernalization(VRtrtr)loci are characterised.Yemalization requirementand the threemajor growth habits of Triticeae (facultative,winter and spring) are deťrnedon the basis of the two-locus VRN-2IVRN-I epistaticmodel. Major photoperiodicallyregulatedgenes,which influencethe transitionto flowering, are characterisedand their interactionswith /fiN genesare briefly discussed.The phenomenonof inductionof FrT duringtheprocessof cold acclimation(CA) is describedand themajorcold-inducedCorlLea genesarelisted.Importantregulatorymechanisms,r.e.,CBF pathway,controllingthe expressionof Corllea genesundercold, are discussed.The major loci affecting the development of FrT in Triticeae, the Fr loci, are characterised.In conclusion,currentprogressin thisresearchfield is summarizedandnew questionsarisingin theareaareformulated. l ) .l .l Ťa I ! .a Ý I 2l I I Rukopis 2 The...
|
|
| |
|
| |
guest ::
RSS feed.