H E B R E W  U N I V E R S I T Y  O F  J E R U S A L E M The Robert H. Smith Faculty of Agriculture, Food and Environment DEPARTMENT OF  ENTOMOLOGY

Department Of Entomology The Robert H. Smith Faculty of Agriculture, Food and Environment P.O Box 12, Rehovot 76100, ISRAEL Tel:  972-8-9489365 Lab: 972-8-9489271 Fax: 972-8-9466768 e-mail address: morin@agri.huji.ac.il

HIGHER EDUCATION 

1988-1991       Hebrew University of Jerusalem, Faculty of Medicine, Medicine, B.Sc.

1992-1995      Hebrew University of Jerusalem, Faculty of Agricultural, Pathogen-Vector-Interaction, M.Sc. Supervisor: Prof. Hanokh                                    Czosnek. Magna cum laude.
1995-2000      Hebrew University of Jerusalem, Faculty of Agriculture, Pathogen-Vector-Interaction, Ph.D. Supervisor: Prof. Hanokh                                            Czosnek.
2000-2003      University of Arizona, Tucson, Department of Entomology, Genetics and Ecology of Insecticide Resistance, Post-Doctoral                         studies. Host: Prof. Bruce Tabashnik.

ACTIVE RESEARCH GRANTS

2004-2008    Israel Science Foundation (ISF), "Ecology and genomics of biotype complexity in Bemisia tabaci".

2004-2006   Council for Higher Education, Planning and Budgeting Committee (Alon 'Young Scientists' Grant), "Ecology and genomics of    biotype complexity in Bemisia tabaci ".

2004-2006   Bayer CropScience, "Using Genetic and Genomic Approaches to Develop Strategies to prevent Evolution of Resistance to

                    Neonicotinoid Insecticides by the Whitefly Bemisia tabaci".

2005-2006   Hebrew University – Novel Proposals – Vigbani Foundation, "Metabolic gene expression as a new approach for studying polyphagy in insects".

2005-2008  United States Department of Agriculture-National Research Initiative Competitive Grants Program (USDA-NRI), "Genetics and Management of Whitefly Resistance to Pyriproxifen".

2005-2007   State of Israel, Ministry of Agriculture and Rural Development, Plant Protection and Inspection Services (PPIS), "Developing  molecular markers for taxonomic definition of spider mite (Tetranychidae) species in Israel and for identification of new invasive species".

M.SC. AND PH.D. STUDENTS

Master's degree students:

2004-            Navit Lahav

2004-            Michal Alon

2004-            Fishel Alon

2004-            Haggai breslauer, co-supervisor with Dr. Rami Horowitz

2005-            Einat Laor

Doctoral degree students:

2003-            Iris Karunker

2003-            Tslila Ben-David, co-supervisor with Prof. Uri Gerson

2004-            Moshe Elbaz

TEACHING

                     'Introduction to Pest Control in Agriculture' (71515, Semester A, B.Sc.-3^rd year).

                     'Proseminar A in Plant Protection' (71504; Semester B; B.Sc.-2^nd year).

'Proseminar B in Plant Protection' (71500; Semester A, B.Sc.-3^rd year).

                     'Introduction to Molecular Biology' (71065; Semester A; B.Sc.-2^nd year)

RESEARCH INTERESTS AND ACTIVITY

My research interests are in population genetics, as they relate specifically to insect-plant and insect-environment interaction. In my work I am focusing on molecular mechanisms underlying pest adaptation to plants and to chemical control tactics used in agronomic systems.

Understanding adaptation as a process means tracing out all of its stages, from the mechanistic study of genetic variants effects on their carriers phenotypes to assessing the biological performance differences, hence resulting fitness differences, among the variants in their natural and agricultural ecosystem settings. I am interested not only in identifying the insect key defensive mechanisms but also in determining their molecular mode of action in the general aspects of the process: organism-environment interactions leading to performance differences in the field.

Since I took my position at the Hebrew University, my research is focusing on adaptation of insects pests to environmental stress and on plant-insect interactions. My goal is to develop and integrate molecular research tools with genetic and ecological studies in field populations. We are witnessing today a revolution in genetics due to the development of molecular tools that study the complete genome and its protein expression profile. However, so far very little work has been done on insects that are major pests of agriculture. Therefore, I have selected model organisms that are considered major pests of agriculture, the whitefly Bemisia tabaci and the spider-mites family Tetranychidae. In my laboratory we are developing basic genomic tools such as cDNA expression library related to stress response and several molecular markers (AFLP, COI, ITS2) for our model organisms. These molecular tools are incorporated and applied to ongoing projects that study pest population dynamics and adaptation to environmental stress: inter-species competition, heat and cold tolerance, alternation of hosts and chemical control. Below I present a brief summary of the major projects currently conducted in my lab:

(1) Ecology and genomics of biotype complexity in Bemisia tabaci - Supported by a grant from the Israel Science Foundation. The work is conducted by Moshe elbaz (Ph.D. student), Navit Lahav (M.Sc. student) and Fishel Alon (M.Sc. student). In this project we use the whitefly Bemisia tabaci as our model organism. Bemisia tabaci has acquired many adaptive genetic changes because it was subjected to strong selection by chemical, natural, biological, and cultural pest-suppression tactics for many years. We focus on characterizing the molecular changes that occur during ecological specialization of Bemisia tabaci. We postulate that specialization is driven by fitness trade-offs between genes that respond to different ecological constrains. We merge ecological and genomics concepts by utilizing two complementary research approaches: i) ecological studies; ii) quantitative gene expression studies. Ecological studies refer to experimental manipulation of the environment for a series of comparisons between sympatric Bemisia tabaci biotypes (biotypes B and Q) that differ in biological process of interest. Quantitative gene expression studies reveal regulatory variation in candidate genes at their ecological context.  

(2) Metabolic gene expression as a new approach for studying polyphagy in insects - Supported by a grant from the Hebrew University – Novel Proposals – Vigbani Foundation. The work is conducted by Michal Alon (M.Sc. student). The majority of herbivorous insects are oligophagous, meaning that they specialize on a relatively narrow range of host plants (three or fewer plant families). Such specialization is thought to reduce competition for food from other herbivores and to lower predation/parasitoid risk, but may compromise a specialist's ability to make use of alternative food sources. On the contrary, a small proportion of insect herbivores, including some of the world's most important agricultural pests, are polyphagous, meaning that they are capable of feeding on a wide range of plant families. How polyphagous species cope with such diversity and unpredictability remains largely unknown at both the genetic and molecular levels. We would expect the diverse diet to necessitate a relatively non-specific generalized detoxification mechanism. The most studied forms of generalized resistance to plant secondary metabolites are metabolic defenses involving glutathione S-transferases (GSTs), various esterases, and cytochrome P450 monooxygenases (P450s). The goal of this proposal is to characterize insect polyphagy at the molecular level. Our model system includes again the whitefly Bemisia tabaci, which is a worldwide pest of vegetable, ornamental, and field crops. Using a microarray chip holding genes that code for P-450s, esterases and GSTs detoxification enzymes, different biotypes of Bemisia tabaci are compared by their metabolic expression profile and by their performance on different plant hosts. We expect this approach to be more accurate and informative in explaining global success of some polyphagous biotypes of Bemisia tabaci. Also, we hope it will allow predicting which newly collected and uncharacterized populations around the globe harbor the potential to become serious pests of different cropping systems.

(3) Multiple origins versus single origin of insecticide resistance in sympatric biotypes of Bemisia tabaci - Supported by grants from Bayer CropScience and the United States Department of Agriculture-National Research Initiative Competitive Grants Program. The work is conducted by Michal Alon and Einat Laor (M.Sc. students) and Iris Karunker (Ph.D. student). We focus on evolution of resistance to three different groups of insecticides: Pyrethroids targeting the para-type voltage gated sodium channel; Neonicotinoids, which are nicotinic acetylcholine receptor agonists and juvenile hormone (JH) mimics that interfere with normal development (especially the molting process). In all three projects we have two scientific goals: (1) to characterize molecularly the resistance mechanism; (2) to explore whether resistance has evolved once or multiple times in the B and Q sympatric biotypes of Bemisia tabaci. These analyses can also clarify the extent of reproductive isolation between these two closely related taxa.

(4) Developing molecular markers for taxonomic definition of spider mite (Tetranychidae) species in Israel and for identification of new invasive species – Supported by a grant from the State of Israel, Ministry of Agriculture and Rural Development, Plant Protection and Inspection Services (PPIS). The work is conducted by Tslila Ben-David (Ph.D. student) and is done in collaboration with Prof. Uri Gerson (Hebrew University, Department of Entomology). The precise identification of taxa in the family Tetranychidae (spider mites) is problematic due to the similarity between species and the limited number of available morphological characters. In addition, both sexes of many species, especially in the large and economically-important genera Oligonychus and Tetranychus, are often needed to arrive at exact determinations. The spider mites of Israel are poorly known, as only about a dozen species (of which most are pests) have so far been recorded. Several formerly-unrecorded or undescribed taxa are also at hand. In addition, other pest species may arrive as a result of the ever-increasing international transfer of commercial plants. Thus it has become imperative to develop, in addition to the morphological methods, molecular means for the rapid and precise identification of these mites. In this project, we use the ribosomal second internal transcribed spaces (ITS2) sequence as a molecular marker. So far, we have molecularly characterized 15 spider mites species, most being pests for which no former sequences were available. We use the data in order to: develop a molecular catalog of the spider mites family in Israel; conduct phylogenetic analysis for identifying disagreements between morphological and molecular taxonomy; conduct population genetics analysis on two important agricultural pest species, Tetranychus urticae and Eutetranychus orientalis, for identifying events of limited gene flow between populations that may be related to different selection processes such as invasion of new habitats.  

PUBLICATIONS 

CHAPTERS IN COLLECTIONS 

1.  Czosnek, H., Morin,  S., Rubinstein, G., Fridman, V., Zeidan, M. and Ghanim, M. (2000). Tomato Yellow Leaf Curl Virus, a Sexually Transmitted Disease of Whiteflies. In "Virus-Vector-Plant Interactions", Harris, K. F., Duffus, J. E. and Smith, O. P. Eds., Academic Press Inc. Elsevier Science, San-Diego, USA. pp. 1-27.

2.   Morin, S.  and Horowitz, R. (2006). Resistance of the TYLCV whitefly vector Bemisia tabaci to insecticides. In "Tomato Yellow Leaf Curl Virus Disease: Management, Molecular Biology and Breeding for Resistance ", Czosnek , H. Ed., Kluwer Academic Publishers, Dordrecht, The Netherlands. In preparation.

ARTICLES 

1.      Ghanim, M., Morin, S., Zeidan, M. and Czosnek, H. (1998). Evidence for transovarial transmission of tomato yellow leaf curl virus by its   vector the whitefly Bemisia tabaci. Virology 240:295-303.

2.      Morin, S., Ghanim, M., Zeidan, M., Czosnek, H., Verbeek, M. and van den Heuvel, J. (1999). A GroEL homologue from endosymbiotic bacteria of Bemisia tabaci is implicated in the circulative transmission of Tomato yellow leaf curl virus. Virology 256:75-84.

3.      Rubinstein, G., Morin, S. and Czosnek, H. (1999). Transmission of tomato yellow leaf curl geminivirus to Imidacloprid treated tomato plants by the whitefly Bemisia tabaci (Homoptera: Aleyrodidae). J. Econ. Entomol.

4.      Morin, S., Ghanim, M., Sobol,  I and Czosnek, H. (2000). The GroEL protein of the whitefly Bemisia tabaci interacts with the coat protein of transmissible and nontransmissible begomoviruses in the yeast two-hybrid system. Virology 276:404-416. 3.071;

5.      Ghanim, M., Morin, S. and Czosnek, H. (2001). Rate of Tomato yellow leaf curl virus translocation in the circulative transmission pathway of its vector, the whitefly Bemisia tabaci. Phytopathology 91:188-196.

6.      Czosnek, H., Ghanim, M., Morin, S., Rubinstein, G., Fridman, V. and Zeidan, M. (2001). Whiteflies: Vectors, and victims (?), of geminiviruses. Adv. Virus Res. 57:291-322.

7.      Morin, S., Brown, J.K., Williamson, M.S., Goodson, S.J., Tabashnik, B.E. and Dennehy, T.J. (2002). Mutations in the Bemisia tabaci para sodium channel gene associated with resistance to a pyrethroid plus organophosphate mixture. Insect Biochem. Mol. Biol. 32:1781-1791.

8.      Morin, S., Sisterson, M., Biggs, R., Shriver, L., Ellers-Kirk, C., Brown, J.K., Higginson, D., Holley, D., Gahan, L., Dennehy, T.J., Carrière, Y., Heckel, D.  and Tabashnik, B.E. (2003). Three cadherin alleles associated with resistance to Bacillus thuringiensis in pink bollworm. Proc. Natl. Acad. Sci. U. S. A. 100: 5004-5009.

9.      Tabashnik, B.E., Carrière, Y., Dennehy, T. J., Morin, S., Sisterson, M., Roush, R.T., Shelton, A.M. and Zhao, J.Z. (2003). Insect Resistance to Transgenic Bt Crops: Lessons from the laboratory and field. J. Econ. Entomol. 96:1031-1038. 1.283; 13/66 in Entomology; 45.

10.  Morin, S., Henderson, S., Fabrick, J.A.,  Carrière, Y., Dennehy, T.J., Brown, J.K. and Tabashnik B.E. (2004). DNA-based detection of Bt resistance alleles in pink bollworm. Insect Biochem. Mol. Biol. 34: 1225-1233.

11.  Tabashnik, B.E., Liu, Y.B., Unnithan, D.C., Carrière, Y., Dennehy, T.J., and Morin, S. (2004).  Shared genetic basis of resistance to Bt toxin Cry1Ac in independent strains of pink bollworm.  J. Econ. Entomol. 97: 721-726.

12.  Tabashnik, B.E., Biggs, R.W., Higginson, D.M., Henderson, S., Unnithan, D.C., Unnithan, G.C., Ellers-Kirk, C., Sisterson M., Carrière, Y., Dennehy, T.J. and Morin, S. (2005(. Association between resistance to Bt cotton and cadherin genotype in pink bollworm. J. Econ. Entomol. 98: 635-644.

13.  Higginson, D.M., Morin, S., Nyboer, M.E., Biggs, R.W., Tabashnik, B.E. and Carriere, Y. (2005). Evolutionary trade-offs of insect resistance to Bacillus thuringiensis crops: fitness cost affecting paternity. Evolution 59: 915-920.

14.  Khasdan, V., Levin, I., Rosner, A., Morin, S., Kontsedalov, S., Maslenin, l. and Horowitz, A.R. (2005). DNA markers for identifying biotypes B and Q of Bemisia tabaci and studying population dynamics. B. Entomol. Res. 95: 605-613.

15.  Alon, M., Benting, J., Lueke, B., Ponge, T., Alon, F. and Morin, S. (2006). Multiple Origins of Pyrethroid Resistance in Sympatric Biotypes of Bemisia tabaci (Hemiptera: Aleyrodidae). Insect Biochem. Mol. Biol. 36: 71-79.