Root regeneration and differentiation

1.Morphology and anatomy Physiology biochemistry and molecular biology 1.Horticultural aspects Biology of root formation

Biological factors Adventitious roots Competence Induction Determination

induction competence acquisition Determination Competence Explant BUDS ROOTS SOMATIC EMBRYOS CALLUS OTHERS ?

Morphology and anatomy of roots initiated in cuttings

Leaf cutting

Oregano

Root initiation area (RIA) of bean hypocotyle Friedman R. et al. (1979). J. Expt. Botany 30:

Friedman R. et al. (1979). J. Expt. Botany 30:

C=Cortex CA=Cambium PR=Pericycle PRF=Pericycle fibers RIA=Root initiation area X=Xylem XF=Xylem fibers Friedman R. et al. (1979). J. Expt. Botany 30:

vermiculite Water

Physiological and molecular aspects Synthesis of protein and Nucleic acid Respiration, Carbohydrate Metabolism, Peroxidases Content and availability of carbohydrates, minerals and vitamines

External factors Water, light, temperature, humidity' Seasonality Presence of reproductive organs Detachment from mother-plant Auxins

H C C H AuxinsCytokin GA אתילן ABA IAA IBA NAA… Kinetin BA (BAP) 2IP… GA 3 GA 4 GA 7 … בנוסף : חומצה ג ' סמונית ועוד

השפעת ריכוזי IBA (PPM) על יצירת שורשים בייחורי עלי עגבניה

השפעת ריכוזי IAA ( PPM, M ) על יצירת שורשים בצימחי שעועית בשני תחומי ריכוזים

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Steven T. Lund2*, Alan C. Smith, and Wesley P. Hackett Plant Physiol. (1 997) 114: Steven T. Lund2*, Alan C. Smith, and Wesley P. Hackett Plant Physiol. (1 997) 114:

Paclobutrazol Chlormequat Ancymidol

ORTHO-DIHYDROXY-PHENOLS

COFACTOR-4A

The Plant Cell 7: (1995) superroot, a Recessive Mutation in Arabidopsis, Confers Auxin Overproduction W. Boerjan,a M.T. Cervera, M. Delarue, T. Beeckman, W. Dewitte, C. Bellini, M. Caboche, H. Van Onckelen, M. Van Montagu, D. lnzé We have isolated seven allelic recessive Arabidopsis mutants, designated superroot (surl-7 to surl-7), displaying several abnormalities reminiscent of auxin effects. These characteristics include small and epinastic cotyledons, an elongated hypocotyl in which the connection between the stele and cortical and epidermal cells disintegrates, the development of excess adventitious and lateral roots, a reduced number of leaves, and the absence of an inflorescence. When germinated in the dark, surl mutants did not develop the apical hook characteristic of etiolated seedlings. We were able to phenocopy the Surl- phenotype by supplying auxin to wild-type seedlings, to propagate surl explants on phytohormone-deficient medium, and to regenerate shoots from these explants by the addition of cytokinins alone to the culture medium. Analysis by gas chromatography coupled to mass spectrometry indicated increased levels of both free and conjugated indole-3-acetic acid. surl was crossed to the mutant axr2 and the altered-auxin response mutant ctrl. The phenotype of both double mutants was additive. The surl gene was mapped on chromosome 2 at 0.5 centimorgans from the gene encoding phytochrome B.

Superroot mutant of Arabidopsis

השפעת טרנספורמציה עם A. RHIZOGENES (rolA) על יצירת שורשים בייחורי צפורן WT T 2T 1