My research goal is to understand the hormonal mechanisms that induce and regulate plant vascular differentiation, focusing on improving fiber production and wood quality formation in forest trees. The research addresses fundamental issues of plant hormone biology: hormone production, transport pathways and hormonal mechanisms that control the differentiation of various cell types in the xylem and phloem of organized tissues, tumors and galls. We analyze pattern formation of various cell types in trees and herbaceous model plants; study their function, environmental adaptation and evolution from conifers to ring-porous trees. Currently, endogenous hormonal concentrations are being modified with molecular and physiological tools for improving wood quality, increasing long fiber production and reducing resin cavities.
* Dayan J, Schwarzkopf M, Avni A, Aloni R (2010) Enhancing plant growth and fiber production by silencing GA 2-oxidase . Plant Biotechnology J 8 : 425–435. -- A new general method how to increase the endogenous concentrations of active gibberellin resulting in elevated fiber content and larger plants .
* Aloni R (2010) The induction of vascular tissue by auxin. In: Plant Hormones: Biosynthesis, Signal Transduction, Action! PJ Davies (ed), Revised 3rd ed, Kluwer Academic Publishers, Dordrecht, Boston, London. pp 485-506. -- Review with two hypotheses (first on auxin transport pathways and the second on the control of xylem maturation patterns) and evidence on the role of auxin in controlling plant vascular tissues.
Galon Y, Aloni R, Nachmias D, Snir O, Feldmesser E, Scrase-Field S, Boyce JM, Bouche´ N, Knight MR, Fromm H (2010) Calmodulin-binding transcription activator 1 mediates auxin signaling and responds to stresses in Arabidopsis . Planta 232:165–178.
Damari-Weissler H, Rachamilevitch S, Aloni R, German MA, Cohen S, Zwieniecki MA, Holbrook NM, Granot D (2009) LeFRK2 is required for phloem and xylem differentiation and the transport of both sugar and water. Planta 230:795–805.
* Aloni R (2007) Phytohormonal mechanisms that control wood quality formation in young and mature trees. In: The Compromised Wood Workshop 2007. K Entwistle, P Harris, J Walker (eds). The Wood Technology Research Centre, University of Canterbury, Christchurch, New Zealand, pp 1-22. -- Review with new ideas how to increase fiber production and decrease resin cavities in trees.
Aloni R, Ullrich CI (2007) Biology of crown gall tumors. In: Agrobacterium. T. Tzfira and V. Citovsky (eds), Springer, Berlin, pp 525-549.
Aloni R, Avni A, Dayan J (2006) Kenaf Gibberellin 2-Oxidase. A provisional USA Patent 60/802,516 2006, filed 23/05/2006. -- A new method to increase the endogenous concentrations of active gibberellin resulting in elevated fiber content and larger Kenaf plants.
* Aloni R, Aloni E, Langhans M, Ullrich CI (2006) Role of cytokinin and auxin in shaping root architecture: regulating vascular differentiation, lateral root initiation, root apical dominance and root gravitropism. Ann Bot 97: 883-893. Review with the hypothesis on the hormonal regulation of lateral root initiation, and evidence on the role of cytokinin and auxin in controlling the root's vascular tissues, apical dominance and gravitropism.
Aloni R, Aloni E, Langhans M, Ullrich CI (2006) Role of auxin in regulating Arabidopsis flower development. Planta 223: 315-328. -- Evidence how auxin produced in flowers synchronizes the development of genetically induced floral organs and controls reproductive morphogenesis from flower initiation to polar seed development.
Chalupowicz L, Barash I, Schwartz M, Aloni R, Manulis S (2006) Comparative anatomy of gall development on Gypsophila paniculata induced by bacteria with different mechanisms of pathogenicity. Planta 224: 429-437.
Aloni R , Ullrich CI (2005) Tumor-induced ethylene controls crown gall morphogenesis. Essay 22.1, Plant hysiology Online, www.plantphys.net
Aloni R, Langhans M, Aloni E, Dreieicher E, Ullrich CI (2005) Root-synthesized cytokinin in Arabidopsis is distributed in the shoot by the transpiration stream. J Exp Bot 56: 1535-1544.
Aloni R, Langhans M, Aloni E, Ullrich CI (2004) Role of cytokinin in the regulation of root gravitropism. Planta 220: 177-182. -- Evidence that cytokinin synthesized in the root cap regulates the early stage of root bending during gravity response.
* Aloni R, Schwalm K, Langhans M, Ullrich CI (2003) Gradual shifts in sites of free-auxin production during leaf-primordium development and their role in vascular differentiation and leaf morphogenesis in Arabidopsis. Planta 216: 841-853. -- Confirmation of the "leaf-venation hypothesis" (Aloni 2001), showing where auxin is produced and how auxin induces polar vein patterns in leaves.
* Aloni R (2001) Foliar and axial aspects of vascular differentiation: hypotheses and evidence. J Plant Growth Regul 20: 22-34. -- Review suggesting the "leaf-venation hypothesis" and evidence on the role of auxin and cytokinin in controlling plant vascular tissues.
Aloni R, Wolf A, Feigenbaum P, Avni A, Klee HJ (1998) The Never ripe mutant provides evidence that tumor-induced ethylene controls the morphogenesis of Agrobacterium tumefaciens-induced crown galls on tomato stems. Plant Physiol 117: 841-849.
Aloni R (1991) Wood formation in deciduous hardwood trees. In: Physiology of Trees. AS Raghavendra (ed), John Wiley & Sons, New York, London, Sydney, pp 175-197. -- Hypothesis and evidence showing how the advanced xylem of ring-porous trees has developed during evolution under stress conditions from the wood of diffuse-porous trees.
Aloni R (1987) Differentiation of vascular tissues. Annu Rev Plant Physiol 38: 179-204. -- Review with the hypothesis explaining vascular adaptation to the plant’s environment [cited by more than 250 papers].
Aloni R, Zimmermann MH (1983) The control of vessel size and density along the plant axis - a new hypothesis. Differentiation 24: 203-208. -- Hypothesis and evidence explaining how auxin controls gradients of vessel width and number in trees.
Aloni R (1985) Plant growth method and composition. United States of America, Patent No 4507144. -- An agricultural method for increasing fiber yield in industrial plants. During plant development, combinations of auxin and gibberellin are applied [the method is demonstrated in my two photos published in Nature (1987) 327: 582].
Aloni R (1979) Role of auxin and gibberellin in differentiation of primary phloem fibers. Plant Physiol 63: 609-614. -- The paper shows that while auxin controls vascular differentiation, the gibberellin is the specific signal which induces fiber differentiation. This basic knowledge enabled to develop agricultural methods (see above: Aloni 1985 and Aloni et al. 2006) to increase fiber production in industrial plants and forest trees.
CITATIONS IN WORLD LEADING TEXT BOOKS
: Evert RF (2006) Esau’s Plant Anatomy, Meristems,
Cells, and Tissues of the Plant Body: Their Structure,
Function, and Development 3rd edition, Wiley
& Sons, Hoboken, New Jersey, USA, the following
2 figures and their related text have originated from
my work: Figure 5.14 (page 122); Fig. 13.2 (p. 359).