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4. A global synthesis reveals biodiversity-mediated benefits for crop production.

Author

Dainese, Matteo, Martin, Emily A, Aizen, Marcelo A, Albrecht, Matthias, Bartomeus, Ignasi, Bommarco, Riccardo, Carvalheiro, Luisa G, Chaplin-Kramer, Rebecca, Gagic, Vesna, Garibaldi, Lucas A, Ghazoul, Jaboury, Grab, Heather, Jonsson, Mattias, Karp, Daniel S, Kennedy, Christina M, Kleijn, David, Kremen, Claire, Landis, Douglas A, Letourneau, Deborah K, Marini, Lorenzo, Poveda, Katja, Rader, Romina, Smith, Henrik G, Tscharntke, Teja, Andersson, Georg KS, Badenhausser, Isabelle, Baensch, Svenja, Bezerra, Antonio Diego M, Bianchi, Felix JJA, Boreux, Virginie, Bretagnolle, Vincent, Caballero-Lopez, Berta, Cavigliasso, Pablo, Ćetković, Aleksandar, Chacoff, Natacha P, Classen, Alice, Cusser, Sarah, da Silva E Silva, Felipe D, de Groot, G Arjen, Dudenhöffer, Jan H, Ekroos, Johan, Fijen, Thijs, Franck, Pierre, Freitas, Breno M, Garratt, Michael PD, Gratton, Claudio, Hipólito, Juliana, Holzschuh, Andrea, Hunt, Lauren, Iverson, Aaron L, Jha, Shalene, Keasar, Tamar, Kim, Tania N, Kishinevsky, Miriam, Klatt, Björn K, Klein, Alexandra-Maria, Krewenka, Kristin M, Krishnan, Smitha, Larsen, Ashley E, Lavigne, Claire, Liere, Heidi, Maas, Bea, Mallinger, Rachel E, Martinez Pachon, Eliana, Martínez-Salinas, Alejandra, Meehan, Timothy D, Mitchell, Matthew GE, Molina, Gonzalo AR, Nesper, Maike, Nilsson, Lovisa, O'Rourke, Megan E, Peters, Marcell K, Plećaš, Milan, Potts, Simon G, Ramos, Davi de L, Rosenheim, Jay A, Rundlöf, Maj, Rusch, Adrien, Sáez, Agustín, Scheper, Jeroen, Schleuning, Matthias, Schmack, Julia M, Sciligo, Amber R, Seymour, Colleen, Stanley, Dara A, Stewart, Rebecca, Stout, Jane C, Sutter, Louis, Takada, Mayura B, Taki, Hisatomo, Tamburini, Giovanni, Tschumi, Matthias, Viana, Blandina F, Westphal, Catrin, Willcox, Bryony K, Wratten, Stephen D, Yoshioka, Akira, Zaragoza-Trello, Carlos, Zhang, Wei, and Zou, Yi

Subjects
Humans, Crops, Agricultural, Ecosystem, Biodiversity, Pest Control, Biological, Agriculture, Pollination, Crop Production, Crops, Agricultural, Pest Control, Biological
Abstract

Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.

Published
2019

5. Crop pests and predators exhibit inconsistent responses to surrounding landscape composition.

Author

Karp, Daniel S, Chaplin-Kramer, Rebecca, Meehan, Timothy D, Martin, Emily A, DeClerck, Fabrice, Grab, Heather, Gratton, Claudio, Hunt, Lauren, Larsen, Ashley E, Martínez-Salinas, Alejandra, O'Rourke, Megan E, Rusch, Adrien, Poveda, Katja, Jonsson, Mattias, Rosenheim, Jay A, Schellhorn, Nancy A, Tscharntke, Teja, Wratten, Stephen D, Zhang, Wei, Iverson, Aaron L, Adler, Lynn S, Albrecht, Matthias, Alignier, Audrey, Angelella, Gina M, Zubair Anjum, Muhammad, Avelino, Jacques, Batáry, Péter, Baveco, Johannes M, Bianchi, Felix JJA, Birkhofer, Klaus, Bohnenblust, Eric W, Bommarco, Riccardo, Brewer, Michael J, Caballero-López, Berta, Carrière, Yves, Carvalheiro, Luísa G, Cayuela, Luis, Centrella, Mary, Ćetković, Aleksandar, Henri, Dominic Charles, Chabert, Ariane, Costamagna, Alejandro C, De la Mora, Aldo, de Kraker, Joop, Desneux, Nicolas, Diehl, Eva, Diekötter, Tim, Dormann, Carsten F, Eckberg, James O, Entling, Martin H, Fiedler, Daniela, Franck, Pierre, Frank van Veen, FJ, Frank, Thomas, Gagic, Vesna, Garratt, Michael PD, Getachew, Awraris, Gonthier, David J, Goodell, Peter B, Graziosi, Ignazio, Groves, Russell L, Gurr, Geoff M, Hajian-Forooshani, Zachary, Heimpel, George E, Herrmann, John D, Huseth, Anders S, Inclán, Diego J, Ingrao, Adam J, Iv, Phirun, Jacot, Katja, Johnson, Gregg A, Jones, Laura, Kaiser, Marina, Kaser, Joe M, Keasar, Tamar, Kim, Tania N, Kishinevsky, Miriam, Landis, Douglas A, Lavandero, Blas, Lavigne, Claire, Le Ralec, Anne, Lemessa, Debissa, Letourneau, Deborah K, Liere, Heidi, Lu, Yanhui, Lubin, Yael, Luttermoser, Tim, Maas, Bea, Mace, Kevi, Madeira, Filipe, Mader, Viktoria, Cortesero, Anne Marie, Marini, Lorenzo, Martinez, Eliana, Martinson, Holly M, Menozzi, Philippe, Mitchell, Matthew GE, Miyashita, Tadashi, Molina, Gonzalo AR, and Molina-Montenegro, Marco A

Subjects
Animals, Crops, Agricultural, Ecosystem, Pest Control, Biological, Models, Biological, agroecology, biodiversity, biological control, ecosystem services, natural enemies, Crops, Agricultural, Pest Control, Biological, Models
Abstract

The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win-win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.

Published
2018

17. An Evaluation of Web Enhanced Instruction in College Level Biology Courses

Author

Keasar, Tamar, Baruch, Rachel, and Grobgeld-Dahan, Esther

Abstract

Websites that accompany science courses typically aim to provide easy access to learning materials, and to facilitate student-instructor communication. We tested whether these aims were achieved in two web enhanced, lower division undergraduate biology courses in an Israeli college. We collected data on the students' attitudes through pre- and post-course questionnaires, monitored their usage of the course websites, and related these data to the students' final course grades. The students (n=96) accessed the websites frequently and regularly, and regarded them as important sources of information. About 47% of the students reported an increased level of general interest in the courses due to the websites. Students mainly downloaded lecture slides and exercise forms from the websites, but did not use the sites to communicate among themselves, or with the instructor. Final course grades were not correlated with the frequency of usage of the website. Female students had a more positive pre-course attitude towards the websites as compared with male students. However, there was no difference between men and women in usage of the course websites, and in achievement levels. We conclude that the website component of the courses in our study facilitated delivery of learning materials and individual study, but not the social aspects of learning. We suggest that effective design of web enhanced courses can overcome this limitation by stressing social interactions and group learning during face to face sessions. (Contains 4 tables and 1 figure.)

Published
2005

26. Effect of Weed Management on the Parasitoid Community in Mediterranean Vineyards

Author

Keasar Tamar, Möller Daniella, Segoli Michal, Ferrante Marco, Möller Gabriella, and Shapira Idan

Subjects
0106 biological sciences, conservation biological control, non-crop vegetation, Biology, natural enemies, 010603 evolutionary biology, 01 natural sciences, Vineyard, General Biochemistry, Genetics and Molecular Biology, Article, vineyards, Abundance (ecology), Community Composition, Weed Management, community composition, Cover crop, lcsh:QH301-705.5, Natural Enemies, General Immunology and Microbiology, Parasitoids, Vegetation, Weed control, Vineyards, parasitoids, 010602 entomology, Agronomy, lcsh:Biology (General), Non-crop Vegetation, Conservation Biological Control, Species richness, General Agricultural and Biological Sciences, Soil conservation, Weed, weed management
Abstract

Enriching agroecosystems with non-crop vegetation is a popular strategy for conservation biocontrol. In vineyards, the effects of specific seeded or planted cover crops on natural enemies are well-studied, whereas conserving spontaneously developing weeds received less attention. We compared parasitoid communities between matched pairs of vineyard plots in northern Israel, differing in weed management practices: &ldquo, herbicide&rdquo, repeated herbicide applications vs. &ldquo, ground cover&rdquo, maintaining resident weeds and trimming them when needed. Using suction sampling, we assessed the parasitoids&rsquo, abundance, richness, and composition during three grape-growing seasons. Ground cover plots had greater parasitoid abundances and cumulative species richness than herbicide-treated plots, possibly because of their higher vegetation cover and richness. Dominant parasitoid species varied in their magnitude and direction of response to weed management. Their responses seem to combine tracking of host distributions with attraction to additional vegetation-provided resources. Parasitoid community composition was mildly yet significantly influenced by weed management, while season, year, and habitat (weeds vs. vine) had stronger effects. Vineyard weeds thus support local biocontrol agents and provide additional previously demonstrated benefits (e.g., soil conservation, lower agrochemical exposure) but might also attract some crop pests. When the benefits outweigh this risk, weed conservation seems a promising step towards more sustainable agricultural management.

Published
2020

40. Abstracts of Presentations at the 18th Conference of the Entomological Society of Israel: May 18, 2000 Aro, The Volcani Center, Bet Dagan, Israel

Author

Pener, M. P., Anshelevich, L., Dunkelblum, E., Hard, M., Harari, A., Gordon, D., Kehat, M., Reuveny, H., Akunis, O., Oppenheim, D., Dunkelblum, E., Rafaeli, Acta, Gileadi, Carina, Hirashima, Akinori, Lubin, Yael, Papke, Mirjam, Soroker, Victoria, Hefetz, A., Klein, Z., Zarabi, Leah, Ovadia, S., Blachinsky, Dafna, Zemer, B., Tadmor, U., Levanon, I., Fish, M., Tadmor, U., Weintraub, Phyllis G., Pener, Hedva, Wilamowski, A., Braverman, Y., Hogsette, J. A., Wilamowski, A., Braverman, Y., Chizov-Ginzburg, A., Pener, Hedva, Braverman, Y., Shlosberg, A., Chizov-Ginzburg, A., Kostyukovsky, M., Shaaya, E., Trostanetsky, A., Bin, C., Barazani, A., Wysoki, M., Rene, S., Eliyahu, Miriam, Blumberg, D., Shofet, Michal, Blachinsky, Dafna, Herzog, Z., Wilamowski, A., Gross, S., Blumberg, D., Mendel, Z., Drishpon, Y., Regev, Avital, Rivkin, H., Chejanovsky, N., Gershburg, E., Froy, O., Gurevitz, M., Avisar, D., Sneh, B., Zilberstein, A., Keller, M., Strizhov, N., Koncz, Sz., Schell, J., Koncz, C., Ben-Dov, E., Zarka, A., Zaritsky, A., Manasherob, R., Boussiba, S., Segal, D., Glazer, I., Altstein, Miriam, Ben-Aziz, Orna, Schefler, Irit, Zeltser, Irina, Gilon, C., Steinitz, B., Navon, A., Navon, A., Levski, Shlomit, Blumberg, D., Nakache, Y., Biton, S., Manasherob, R., Ben-Dov, E., Zaritsky, A., Boussiba, S., Wu, X.- Q., Myasnik, M., Manasherob, R., Margalith, Y., Zaritsky, A., Ben-Dov, E., Barak, Z., Azaizeh, H., Gindin, Galina, Barash, I., Klein, M., Golberg, Alla, Blumberg, D., Chizov-Ginzburg, A., Braverman, Y., Giladi, M., Gerling, D., Glazer, I., Salame, L., Goldenberg, S., Blumberg, D., Samish, M., Alekseev, E., Gindin, Galina, Glazer, I., Shaltiel, Liora, Coll, M., Barkely, M., Guershon, M., Groenteman, Ronny, Coll, M., Guershon, M., Borrow, Oshrat, Gerling, D., Samara, M., Gerling, D., Rajuan, Nelli, Gerling, D., David-Levanony, Lishay, Blumberg, D., Mendel, Z., Gafny, R., Havron, A., Eliezer, A., Ben-Dov, Y., Miller, D. R., Gibson, G. A. P., Klein, Z., Zarabi, Leah, Friedman, A. L. L., Freidberg, A., Argaman, Q., Klein, Z., Dias, R., Navarro, S., Donahaye, E., Rindner, Miriam, Azrieli, A., Hovevey-Zion, D., Hamburger, Mirit, Zarabi, Leah, Keidar, H., Sompolinsky, E., Weiss, M., Kuslitzky, W., Klein, Z., Bitten, S., Nakache, J., Saphir, Nitza, Zehavi, A., Assael, Fabienne, Mendel, Z., Gahanama, Liat, Broza, M., Halpern, Malka, Inbar, M., Broza, M., Poliakov, Dina, Mossinson, S., Taylor, P. W., Kaspi, R., Yuval, B., Kaspi, R., Yuval, B., Yerushalmi, Y., Pener, M. P., Dorchin, Netta, Afik, O., Shafir, S., Falach, Lily, Shani, A., Segev, O., Gottlieb, Daphna, Keasar, Tamar, Shmida, A., Motro, U., Menda, G., Shafir, S., Ben-Yakir, D., Chen, M., Teitel, M., Barak, M., Berlinger, M. J., Lebiush-Mordechai, Sara, Messika, Y., Shamia, Y., Rosen, D., Ben-Yakir, D., Chen, M., Hamburger, Mirit, Zarabi, Leah, Weiss, M., Argaman, Q., Kuslitzky, W., Klein, Z., Bar-Shalom, O., Mendel, Z., Malihi, Y., Gerling, D., Freidberg, A., Ben-Yehuda, S., Mendel, Z., Franco, J. C., Carvalho, C. J., Gross, S., Blumberg, D., Mendel, Z., Wool, D., Cohen, Hadass, Yuval, B., Mazor, Michal, Peysakhis, A., Ginzburg, A., Argov, Yael, Voet, H., Palcvsky, E., Chyzik, Raisa, Ucko, Orna, Peles, S., and Gerson, U.

Published
2001
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42. The spatial distribution of nonrewarding artificial flowers affects pollinator attraction

Author

Keasar, Tamar

Subjects
Artificial flowers -- Usage, Bumblebees -- Behavior, Pollination by insects -- Observations, Zoology and wildlife conservation
Abstract

Studies have indicated that the foraging of insect pollinators may be influenced by early blooming and colour polymorphism. A further investigation using bumblebees considers whether pollinator behaviour favours aggregated flowering in orchid species.

Published
2000

45. Sugar feeding of parasitoids in an agroecosystem: effects of community composition, habitat and vegetation

Author

Kishinevsky, Miriam, Cohen, Nitzan, Chiel, Elad, Wajnberg, Eric, Keasar, Tamar, Schonrogge, Karsten, Brady, Seán, University of Haifa [Haifa], Agricultural Research Organisation (ARO), Volcani Center, Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria), HExapode, PHysiologie, AssISTance et Objets de Service (HEPHAISTOS), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Centre for Ecology and Hydrology [Wallingford] (CEH), Natural Environment Research Council (NERC), Rockefeller University [New York], and Israeli Ministry of Agriculture and Rural Development

Subjects
0106 biological sciences, Agroecosystem, Honeydew, sugar feeding, Ecology, fungi, Foraging, Encarsia inaron, nectar, Biology, biology.organism_classification, 010603 evolutionary biology, 01 natural sciences, Parasitoid, 010602 entomology, Aphelinidae, Agronomy, Insect Science, Nectar, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Cold anthrone test, Sugar, Ecology, Evolution, Behavior and Systematics, honeydew
Abstract

International audience; Sugar from nectar or from honeydew can prolong parasitoids’ lifespan, enhance their fecundity and foraging ability, and thereby increase their pest suppression efficiency. Sugar sources within crop monocultures are considered to be limiting for parasitoids. Nevertheless, only few studies have measured the sugar feeding of parasitoid assemblages in agricultural areas or in surrounding non-crop habitats. We used cold anthrone tests to compare the frequency of sugar feeding in parasitoid communities, inside pomegranate orchards and in adjacent natural areas, over two consecutive years. Overall, 40% of the 1610 sampled individuals belonging to 135 species scored positive for sugar. Sugar-feeding frequency was lower within the orchards than in the neighbouring natural areas. The proportion of sugar-fed wasps increased with herbaceous vegetation cover, both within and outside the orchards, suggesting that herbs are a sugar-rich habitat. Parasitoids sampled from trees and from herbs within the orchards had similar frequencies of sugar feeding, despite differences in wasp species composition. Our results probably overestimate sugar-feeding frequencies in the field because sugar-fed individuals have higher longevity and hence are more likely to be sampled. We propose a simple model to approximate this over-sampling bias and apply it to Encarsia inaron (Aphelinidae), one of the most abundant parasitoids in the samples. We conclude that sugar availability potentially limits parasitoid fitness in this agro-ecosystem. This may be due to the low density of plants in natural areas during the Mediterranean summer, and to herbicide applications within the orchards that further suppress non-crop herbs.

Published
2017

48. Overnight memory retention of foraging skills by bumblebees is imperfect

Author

Keasar, Tamar, Motro, Uzi, Shur, Yoav, and Shmida, Avi

Subjects
Animal feeding and feeds -- Research, Animal memory -- Research, Bumblebees -- Behavior, Zoology and wildlife conservation
Abstract

The oraging efficiency of naive Bombus terrestris bumblebees declines during the night due to the weakening of memory. A comparative study shows that nectar intake rates increase due to bee's gaining experience during day, while probing time and inter-visit intervals increase during night. Nectar intake rates differ among individual bees. A preference for profitable cluster of flowers is present initially, but later becomes insignificant. The partial forgetting is suggested to help the bees in quick overnight reaction to changes in source.

Published
1996

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