Asunto(s)
Células Fotorreceptoras , Fitocromo/fisiología , Plantas Modificadas Genéticamente/efectos de la radiación , Solanum tuberosum/efectos de la radiación , Factores de Transcripción , Expresión Génica , Fenotipo , Fitocromo/biosíntesis , Fitocromo/genética , Fitocromo B , Componentes Aéreos de las Plantas/crecimiento & desarrollo , Componentes Aéreos de las Plantas/efectos de la radiación , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Tolerancia a Radiación/genética , Solanum tuberosum/genética , Solanum tuberosum/crecimiento & desarrollo , Solanum tuberosum/metabolismo , Factores de Tiempo , Rayos Ultravioleta/efectos adversosAsunto(s)
Adenina/farmacología , Regulación de la Expresión Génica de las Plantas , Fotoperiodo , Células Fotorreceptoras , Fitocromo/fisiología , Reguladores del Crecimiento de las Plantas/metabolismo , Solanum tuberosum/genética , Factores de Transcripción , Adenina/análogos & derivados , Citocininas/biosíntesis , Cinetina , Luz , Fitocromo/genética , Fitocromo/metabolismo , Fitocromo B , Tubérculos de la Planta/efectos de los fármacos , Tubérculos de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente , Solanum tuberosum/crecimiento & desarrolloRESUMEN
Growth and tuber formation of transgenic potato plants (Solanum tuberosum cv. Désirée) harboring the yeast invertase gene and the rolC gene individually or in combination under the transcriptional control of the patatin promoter were investigated under different conditions in vitro. Plants expressing only the invertase gene were morphologically similar to control plants. rolC transgenic plants had an increased tiller number, improved root growth, and a higher total biomass. Tuber formation and growth were altered by the introduced transgenes. The sucrose requirement to induce tubers was shifted to lower or higher concentrations for invertase- or rolC-expressing clones, respectively. In addition, rolC plants formed tubers of altered morphology. A comparison with soil-grown plants showed that morphological parameters can be predicted to some extent from in vitro studies, while for reliable prescreening of parameters concerning tuber formation and growth, an optimization of currently used protocols is necessary.
RESUMEN
The patterns of control of flowering are analyzed in plants of different biotypes. The photoperiodic reaction of flowering taken as an example, the whole net of control is considered: from the environmental stimulus through its physiological transformation in the leaf in the corresponding hormonal impulse which, in turn, controls the realization of genetic programme and formation of generative organs in the stem buds. The photoperiodically neutral plants taken as an example, the patterns of age control of flowering are considered. In plants of different photoperiodic groups the synthesis of complementary components of florigen was shown to proceed either autonomously under the photoperiodic effect or under the inducing effect of definite photoperiods. The autonomous and inducible mechanisms of biosynthesis of the flowering hormones have a common base, the genetic system to which the environment sends its stimuli through the hormonal interactions. The interaction of hormonal and genetic developmental factors is considered, the evocation of flowering in the stem buds taken as an example.