Study of the factors affecting the productivity, yield accumulation and quality of vegetable and field crops. Determining the factors controlling carbohydrate translocation and resource allocation between the various plant organs. Seed development; environmental effect on the viability of seeds; the mechanisms involved in the process of seed germination, with an emphasis on the effect of stressful conditions. Development of technologies for more efficient hybrid seed production.
RESEARCH FIELDS AND INTERESTS
Physiology of Crop Production - Within this area, our main research topic involves transport processes in plants, with an emphasis on carbohydrate metabolism and resource allocation among the various plant organs, using several agronomic crops as model plants.
Following our findings that viral movement proteins (MPs) alter plasmodesmal function, we developed a unique experimental system with which we studied the role of plasmodesmal function in the control of carbon transport in plants. We established that a constitutive expression of viral MPs in transgenic plants, cause a significant alteration in the process of carbon metabolism and resource allocation in plants. Based on these findings, we hypothesized that the control of plasmodesmal function may offer a powerful means of affecting sucrose transport into sink organs. The use of viral MPs to alter sugars content in source leaves and resource allocation to various sink organs is currently being investigated in various agricultural crops.
In light of the findings obtained from our research, we developed the theme that at the whole plant level, the phloem serves as an information superhighway. Such a long-distance communication system may utilize a new class of signaling molecules (proteins and/or RNA) to co-ordinate photosynthesis and carbon/nitrogen metabolism in source leaves with the complex growth requirements of the plant under the prevailing environmental conditions. The discovery that expression of viral MP in plants can induce precise changes in carbon metabolism and photoassimilate allocation provided a conceptual foundation for studies (in our laboratory and around the world) aimed at elucidating the communication network responsible for integrating photosynthetic productivity with resource allocation at the whole-plant level. Such information will surely provide an understanding of how plants coordinate the essential physiological functions performed by distantly separated organs. Our present goal is to identify the signal molecules involved in mediating and controlling the communication between distant plant organs.
Seed production – Within this area, our main research topic includes the study of factors controlling seed quality. One of our main studies has been aimed at exploring the mechanisms enabling low-temperature germination in tomato seeds, where the endosperm layer has been found to be the main physical barrier to germination. The activities of cell-wall-hydrolyzing enzymes are under unique temporal and spatial control. A current study is aimed at cloning tomato endo-mannannases and exploring their role in the control of seed germination using a molecular approach.
- Gil, L., J. Ben-Ari, R. Turgeon and S. Wolf (2012) Effect of CMV infection and high temperatures on the enzymes involved in raffinose family oligosaccharide biosynthesis in melon plants. J. Plant Physiol., in press.
- Schneider, S., S. Hulpke, A. Schulz, I. Yaron, J.Höll, A. Imlau, B Schmitt, S Batz, S. Wolf, R. Hedrich and N. Sauer (2012). Vacuoles release sucrose via tonoplast-localized SUC4-type transporters. Plant Biol., 14:325-336.
- Ruiz-Mederano, R., F. Kragler and S. Wolf (2011) Signaling and phloem-mobile transcripts. In short and Long Signaling, Kragler F and Hulskamp M (eds.). Springer Verlag, New York, Dordrecht, Heidelberg, London, pp. 151-177.
- Aly, R., N. Hamamouch, J. Abu-Nassar, S. Wolf, D.M. Joel, H. Eizenberg, E. Kaisler, C. Cramer, A. Gal-On and J.H. Westwood (2011). Movement of protein and macromolecule between host plant and the parasitic weed Phelipanche aegyptiaca Pers. Plant Cell Rep. 30:2233-2241.
- Gil, L., I. Yaron, D. Shalitin, N. Sauer, R. Turgeon and S. Wolf (2011). Sucrose transporter plays a role in phloem loading in CMV-infected melon plants that are defined as symplastic loaders. Plant J. 66:366-374.
- Shoshani, S., S. Wolf and E. Keinan (2011). Molecular computing with plant cell phenotype serving as quality controlled output. Mol. Biosyst. DOI: 10.1039/C0MB00226G.
- Malter, D. and S Wolf (2011). Melon phloem-sap proteome: developmental control and response to viral infection. Protoplasma 248:271-224.
- Nashilevitz, S., C. Melamed-Bessudo, Y. Izkovich, I. Rogachev, S. Osorio-Algar, M. Itkin, A. Adato, I. Pankratov, J. Hirschberg, A. Fernie, S. Wolf, B. Usadel, A.A. Levy, D. Rumeau and A. Aharoni (2010). An orange ripening mutant links plastid NAD(P)H dehydrogenase complex activity to central and specialized metabolism during tomato fruit maturation. Plant Cell, 22:1977-1997.
- Naschitz, S, A. Naor, S. Genish, S. Wolf and E.E. Goldschmidt (2010). Internal management of non-structural carbohydrate resources in apple leaves and branch wood under a broad range of sink and source manipulations. Tree Physiol. 30:715-727.
- Yogev, A., Y. Hadar, R. Cohen, S. Wolf, L. Gil, J Katan, and M. Raviv (2010). Induced resistance as a putative component of compost suppressiveness. Biological Control 54:46-51.
- Yativ, M., I. Harary, and S. Wolf (2010). Sucrose accumulation in watermelon fruits: Genetic variation and biochemical analysis. J. Plant Physiol. 167:589-596.
- Wolf, S (2009). Phloem long-distance trafficking of proteins and RNAs. In: Encyclopedia of Life Sciences (ELS). John Wiley & Sons, Ltd: Chichester. DOI: 10.1002/9780470015902.a0021260.
- Turgeon, R. and S. Wolf (2009). Phloem transport: Cellular pathways and molecular trafficking. Annu. Rev. Plant Biol. 60:207-221.
- Nashilevitz, S, C. Melamed-Bessudo, A. Aharoni, J. Kossmann, S. Wolf and, A.A. Levy (2009). The legwd mutant uncovers the role of starch phosphorylation in pollen development and germination in tomato. Plant J. 57:1-13.
- Salman-Minkov, A., A. Levi, S. Wolf and T. Trebitsh (2008). ACC synthase genes are polymorphic in watermelon (Cirullus spp.) and differentially expressed in flowers and in response to auxin and gibberellin. Plant Cell Physiol. 49:740-750.
- Omid, A., D. Malter, G. Peleg and S. Wolf (2008). Long-distance trafficking of macromolecules in the phloem. Plant Signaling & Behavior 3:260-262.
- Omid, A., T. Keilin, A. Glass, D. Leshkowitz and S. Wolf (2007). Characterization of phloem-sap transcription profile in melon plants. J. Exp. Bot. 58:3645-3656.
- Belotserkovsky, H., Y. Berger, R. Shahar and S. Wolf (2007). Specific role of LeMAN2 in the control of seed germination exposed by overexpression of the LeMAN3 gene in tomato plants. Planta 227:199-209.
- Peleg, G., D. Malter and S. Wolf (2007). Viral infection enables phloem loading of GFP and long-distance trafficking of the protein. Plant J. 51:165-172.
- Weiss, Y., B. Rubin, A. Shulman, I. Ben Shir, E. Keinan and S. Wolf (2006). Determination of plant resistance to herbicidal compounds inhibiting cell division and early growth by seed and plantlets bioassays. Nature Protocols 1:2282-2287.
- Weiss, Y., A. Shulman, I. Ben Shir, E. Keinan and S. Wolf (2006). Herbicide-resistance conferred by expression of a catalytic antibody in Arabidopsis thaliana. Nature Biotechnol. 24:713-717.
- Safra, L., Z. Shani, A. Danin., L. Roiz., O. Shoseyov and S. Wolf (2006). Growth modulation of transgenic potato plants by heterologous expression of bacterial cellulose-binding domain. Mol. Breed. 17: 355-364.
- Nadler-Hassar, T., A. Goldshmidt, B. Rubin and S. Wolf (2004). Glyphosate inhibits the translocation of green fluorescent protein and sucrose from a transgenic tobacco host to Cuscuta campestris Yunk. Planta 219:790-796.
- Complainville, A., L. Brocard, I. Roberts, E. Dax, N. Sever, N. Sauer, A. Kondorosi, S. Wolf, K. Oparka and M. Crespi (2003). Nodule initiation involves the creation of a new symplasmic field in specific roots cells of Medicago species. Plant Cell 15:2778-2791.
- Guenoune, D., R. Amir, H. Badani, S. Wolf and S. Galili (2003). Coexpression of the soybean vegetative storage proteins β subunit (S-VSPβ) either with the bacterial feedback-insensitive dihydrodipicolinate synthase or with S-VSPα stabilizes the S-VSPβ transgene protein and enhances lysine production in transgenic tobacco plants. Transgenic Res. 12:123-126.
- Complainville, A., I.M. Roberts, N. Sauer, S. Wolf, A. Kondorosi, K.J. Oparka and M. Crespi (2003). Nodule initiation involves the creation of a new symplasmic domain in specific root cells of Medicago ssp. In: Plant Cell Biology Frontiers: Cell-to-cell communication in plants. Ed. Raikhel, N., Riverside, California, USA.
- Crespi, M., A. Complainville, D. Chinchilla, F. Merchan, A. Campalans, C. Breda, C. Sousa, M. Megias, E. Dax, S. Wolf and A. Kondorosi (2002). Functional analysis of regulatory genes involved in M. truncatula nodule organogenesis. In: Nitrogen Fixation: Global Perspectives, Eds. Finan, T.M., O'Brian, M.R., Layzell, D.B., Vessey, J.K.and Newton, W.E., CABI. Publishing: Wallingford, UK, pp. 179-183.
- Guenoune, D., R. Amir, H. Badani, S. Wolf and S. Galili (2002). Combined expression of S-VSPα in two different organelles enhances its accumulation and total lysine production in leaves of transgenic tobacco plants. J. Exp. Bot. 53:1867-1870.
- Shalitin, D., Y. Wang, A. Omid, A. Gal-On and S. Wolf (2002).Cucumber mosaic virus movement protein affects sugar metabolism and transport in tobacco and melon plants. Plant Cell Environ. 25:989-998 (COVER PHOTO).
- Guenoune, D., S. Landau,, R. Amir, H. Badani, L. Devash, S. Wolf and S. Galili (2002). Resistance of soyben vegetative storage proteins (S-VSPs) to proteolysis by rumen microorganisms. J. Agr. Food Chem. 50:2256-2260.
- Xu, G., U. Kafkafi, S. Wolf and Y. Sugimoto (2002). Mother plant nutrition and growth conditions affect amino and fatty acid composition of hybrid sweet pepper seeds. J. Plant. Nutr. 25:1645-1665.
- Xu, G., S. Wolf and U. Kafkafi (2002). Ammonium on potassium interaction in sweet pepper. J. Plant. Nutr. 25:719-734.
- Ephrath, J.E., J. Ben Asher, C. Alekparov, M. Silberbush, S. Wolf and E. Dayan (2001). The effect of temperature on the development of Hippeastrum: A phytotron study. Biotronics 30:51-62.
- Hofius, D., K. Herbers, M. Melzer, A. Omid,, E. Tacke, S. Wolf and U Sonnewald (2001). Evidence for expression level-dependent modulation of carbohydrate status and viral resistance by the potato leafroll virus movement protein in transgenic tobacco plants. Plant J. 28:529-543.
- Xu, G., S. Wolf and U. Kafkafi (2001). Effect of varying nitrogen form and concentration during the growing season on sweet pepper flowering and fruit yield. J. Plant. Nutr. 24:1099-1116.
- Xu, G., S. Wolf and U. Kafkafi (2001). Interactive effect of nutrient concentration and contained volume on flowering, fruiting and nutrient uptake of sweet pepper. J. Plant. Nutr. 24:479-501.
- Tong-Bao, L., S. Wolf, A. Schwartz and Y. Saranga (2000). Silverleaf whitefly stress impairs sugar export from cotton source leaves. Physiol. Plant. 109:291-297.
- Shalitin, D. and S. Wolf (2000). Cucumber mosaic virus infection affects sugar transport in melon plants. Plant Physiol. 123:597-604.
- Shalitin, D. and S. Wolf (2000). Interaction between phloem protein and viral movement proteins. Aust. J. Plant Physiol. 27:801-806.
- Shalitin, D., K. Shamay and S. Wolf (2000). CMV movement protein modifies plasmodesmal function in transgenic melon plants. Acta Hortic., 510:335-341.
Heat stress effects on source-sink relationship and translocation of assimilates in potatoes (1988).
Faculty of Agriculture, The Hebrew University of Jerusalem, 110 pp. (In Hebrew).
Wolf, S. et al. (2004) "Watermelon varieties having altered sugar ratios". Patent application No. PCT/IL2004/000122