41 results on '"E. Chalutz"'
Search Results
2. Application of Hormetic UV-C for Delayed Ripening and Reduction of Rhizopus Soft Rot in Tomatoes: the Effect of Tomatine on Storage Rot Development
- Author
-
Samir Droby, Victor A. Khan, M. K. Kabwe, Clauzell Stevens, C. L. Wilson, E. Chalutz, E. C. K. Igwegbe, J. Y. Lu, and J. Liu
- Subjects
Tomatine ,chemistry.chemical_classification ,Physiology ,Hormesis ,food and beverages ,Spermine ,Ripening ,Plant Science ,Biology ,biology.organism_classification ,chemistry.chemical_compound ,Horticulture ,chemistry ,Rhizopus ,Botany ,Genetics ,Putrescine ,Agronomy and Crop Science ,Carotenoid ,Rhizopus soft rot - Abstract
The application of ultraviolet-light C (UV-C, 254 nm) hormesis on tomato fruits to stimulate beneficial responses is a new method of inducing host resistance to Rhizopus soft rot, with maximum protection at 72 h following artificial inoculation with Rhizopus stolonifer and delay fruit ripening. In the tomato-Rhizopus soft rot pathosystem, UV-C induced resistance of tomatoes to soft rot was reversed by fluorescent light, and not by storage under dark condition. The present study was aimed at finding a possible fungal toxic mechanism that was involved in the control of Rhizopus soft rot. The development of carotenoids, loss of chlorophyll and ethylene production were significantly retarded during storage after treatment with hormetic doses of UV-C. The delayed ripening of UV-C treated fruits was attributed in part to the high level of putrescine and spermine polyamines. In a time-control study, it was found that the resistance of UV-C-treated tomatoes artificially inoculated with R. stolonifer correlated with a high concentration of tomatine which accumulated up to 72 h after UV-C treatment. However, there was a higher tomatine content in UV-C-treated fruits compared to untreated fruits where it was transitory at 96 h after treatment in the time-course study.
- Published
- 1998
3. Abstracts of papers presented at the 8th conference of the Entomological Society of Israel Abstracts of papers presented at the 17th congress of the Israeli Phytopathological Society
- Author
-
Amnon Freidberg, Yoram össler, David Nestel, Smadar Hirsh, Nimrod Israely, Boaz Yuval, Meirav S. Warburg, Sigal Blay, Roy Kaspi, Oren Hasson, Amos Rubin, Arieh Landesman, Edva Zakkay, Ruthi Levy, Salo Meidan, Michal Mazor, Fathi Abd el-Hadi, Y. Gafni, Leah Tsror, Orly Erlich, C. Chen, I. Ben-Ze’ev, G. Kritzman, D. Zutra, I. Assouline, S. Freeman, Miriam Zilberstaine, Edna Levy, I. S. Ben-Zeev, Yael Dlugatch, E. Shabi, Talma Katan, Beth Teviotdale, Marina Hazanovsky, I. Kosto, Galit Sharabani, D. Shtienberg, Y. Elad, A. Dinoor, H. Yunis, J. Manisterski, Pnina Ben-Yehuda, E. Kosman, Z. Eyal, Tamar Eilam, Y. Anikster, S. Pivonia, R. Cohen, I. S. Ben-Ze’ev, U. Kafkafi, J. Katan, M. Edelstein, Rivka Offenbach, A. Gamliel, E. Shlevin, G. Lazarovits, N. Bar-Lev, B. Chefetz, Y. Chen, Y. Hadar, Lea Madi, Y. Mahrer, P. Di Primo, A. Grinstein, I. Peretz Alon, O. Heiman, Z. Bar, E. Serlin, O. Kleifeld, I. Chet, Miriam Abramsky, Iris Yedidia, Y. Henis, V. Rodov, J. Peretz, S. Ben-Yehoshua, U. Afek, Janeta Orenstein, E. Nuriel, M. Austerweil, Tsilah Ben-David, B. Steiner, Yehudit Riven, V. Zilberg, R. Amir, L. Livescu, Marina Hazanovski, M. Aharon, R. Barak, I. Peretz, B. Bing, A. Yaniv, E. Barak, M. Reuveni, Tirza Zehavi, R. Reuveni, E. Fallik, Shoshana Grinberg, O. Ziv, N. Paster, Mazal Menasherov, U. Ravid, Irena Katzir, D. Zohar, J. Dreishpun, Y. Hefer, A. Lior, R. Rodman, H. Katz, E. Chalutz, S. Droby, Lea Cohen, Batia Weiss, A. Daus, Batia Horev, Laura Chalupovicz, E. Yogev, A. Shaknai, D. Beth-Din, M. Berson, A. Sztejnberg, G. Mairovich, J. B. Marder, Smadar Lischinsky, Shulamit Manulis, M. Galperin, Y. Levy, Nadia Korolev, M. A. Flaishman, P. E. Kolattukudy, D. Prusky, C. Wattad, Ilana Kobiler, Y. Cohen, A. Baider, Zipora Reshit, Sonia Farkas, D. Ga’ash, Frieda Kleitman, O. Dror, S. Elisha, I. David, Dalia Rav-David, Z. Herzog, Y. Burger, Shoshana Shraiber, Y. Elkind, Eilit Levin, J. M. Grünzweig, H. D. Rabinowitch, Y. Ben-Tal, Maria Wodner, Z. Solel, N. Mogilner, Miriam Kimchi, R. Gafni, M. Bar-Joseph, Z. Madar, M. Kimchi, J. Riov, S. Oved, O. Yarden, Anat Haviv, I. Barash, J. H. Sietsma, Adi Beth Din, Vered Ziv, K. A. Sjollema, Ronit Greenberg, Shoshana Shreiber, Nurit Katzir, Sara Kalman, D. Zamir, Smadar Pnini-Cohen, Avian Zilberstein, Silvia Schuster, A. Sharon, Y. Rotem, Nava Weiss, R. Shapira, Osnat Eyal, Anyet Matt, R. Salomon, O. Shifer, E. Rosenberg, Ester Hadar, Y. Gottlieb, T. Sando, Tsilla Ben-David, Esther Hadar, J. Cohen, A. Franck, N. Umiel, E. Hadar, S. Finkelstein, A. Gera, S. Levy, D. -E. Lesemann, M. Lapidot, S. Cohen, Rachel Ben-Joseph, S. Ben Harush, M. Pilowsky, C. Shifriss, A. Zelcer, Dalia Wolf, J. -E. Faure, M. Bar, A. Rosner, A. Gal-On, E. Lev, H. Livne, S. Omer, H. Yunes, S. Singer, B. Raccah, Y. Antignus, Malenia Pearlsman, O. Lachman, A. Koren, Francoise Bernardi, C. D. DiFonzo, D. W. Ragsdale, E. B. Radcliffe, M. Mawassi, Elzbieta Mietkiewska, M. E. Hilf, Lilach Ashulin, A. V. Karasev, R. Gafny, R. F. Lee, S. M. Garnsey, W. O. Dawson, G. Yang, A. Frank, V. J. Febres, C. L. Niblett, Rose Gofman, Hinanit Koltai, N. Chejanovsky, Y. Spiegel, Y. Oka, M. Mor, Hadas Cohen, D. Oppenheim, Y. Benyamini, D. Orion, Meira Bar-Eyal, Y. Israeli, and J. Gottlieb
- Subjects
Insect Science ,Ecology (disciplines) ,Library science ,Plant Science ,Biology - Published
- 1996
4. Efficacy ofCandida oleophila strain 182 in preventingPenicillium expansum infection of nectarine fruits
- Author
-
Samir Droby, L. Chalupowicz, S. Lurie, and E. Chalutz
- Subjects
Controlled atmosphere ,Strain (chemistry) ,food and beverages ,Plant Science ,Biology ,biology.organism_classification ,Yeast ,Microbiology ,Fungicide ,Yeast suspension ,Horticulture ,Insect Science ,Postharvest ,Penicillium expansum ,[Candida] oleophila - Abstract
The potential of the yeastCandida oleophila for postharvest control ofPenicillium expansum infection on nectarines was assessed on wound-inoculated fruits held at 20°C, or at 0°C in either air or controlled atmosphere storage. In addition, the efficacy of a prestorage dip with a yeast suspension, the fungicide dicloran, or a combination of the two, for controlling natural infections following storage was examined.C. oleophila reduced the level of infection caused byP. expansum in harvested nectarines. The yeast’s effectiveness was not reduced by controlled atmosphere storage or by application together with the commercial fungicide dicloran.
- Published
- 1995
5. Abstracts of papers presented at the 14th Congress of the Israeli Phytopathological Society Abstracts of papers presented at the 8th Meeting on Whiteflies in Field Crops, Vegetables and Ornamentals
- Author
-
I. S. Ben-Ze’ev, Edna Levy, Osnat Ben-Gal, Y. Shabtay, B. Raccah, S. Singer, J. Katan, Alona Shani, A. Grinstein, G. Kritzman, Shulamit Manulis, Nina Kogen, Michal Reuven, Y. Ben-Yephet, Y. Pinkas, S. Elisha, E. Shabi, Talma Katan, Hilda Gera, P. Sarig, Antoinette Monjauze, N. Lisker, I. Itach, Ruth Ben-Arie, U. Afek, N. Aharoni, S. Carmeli, Rivka Barkai-Golan, Lucy Roizer, A. Lazar, Shoshana Grinberg, Ella Lomaniec, E. Fallik, R. Cohen, Caroline J. Bolter, R. A. Brammall, G. Lazarovits, G. Leibovich, Y. Elkind, H. S. Paris, A. Dinoor, Y. Cohen, Helena Eya, A. Cohen, R. Salomon, A. Bar-Zur, E. Dubitzki, A. Gera, F. Akad, E. Teverovsky, R. Aly, Y. Tam, G. Loebenstein, J. Manisterski, Penina Ben-Yehuda, Esther Nof, Edna Tanne, D. Shtienberg, U. Naphtalyahu, D. Zohar, Y. Hefer, A. Yaniv, Beryl Bernstein, E. Zehr, Shoshana Schreiber, S. Graph, Anat Yogev, Z. Karchi, S. Dori, Z. Solel, I. Barash, Esther Hadar, B. Jacoby, E. Zamski, Y. Rotem, O. Shoseyov, A. Sztejnberg, N. Paster, E. S. Kuttin, Mazal Menasherov, Adi Beth Din, O. Yarden, A. Lichter, O. Sagee, Y. Gafni, J. M. Gruenzweig, H. D. Rabinowitch, M. Mor, M. Gokkes, A. Rosner, Adina Stein, S. Levy, Y. Antignus, Melanie Perlsman, Rachel Ben-Joseph, S. Cohen, D. Levy, Y. Ben-Dov, M. Hecht, Sima Zinger, Francoise Bernardi, O. Lachman, Y. Avidan, M. Mawassi, R. Gafni, D. Shalitin, M. Bar-Joseph, T. Fahima, Y. Wu, P. Kazmierczak, L. Zhang, N. K. Van Alfen, Orly Amzaleg, B. Kirshner, Y. Nitzani, S. Negev, E. Shlevin, A. Gamliel, Ruhama Berliner, M. Heller, I. Gonen, O. Hyman, A. Eshet, Bracha Steiner, Yehudith Rivan, I. Sagi, B. Abramovitz, Y. Dagan, Z. Gotlib, Z. Bar, A. Bazar, O. Cochavi, J. J. Stapleton, Y. Szmulewich, Miriam Lampel, B. Kirschner, Anat Kritzman, Inbar Grinstein, E. Levitin, M. Itach, D. Orion, Meira Bar-Eyal, A. Wiseblum, R. Shorer, Mali Amidror, O. Ziv, A. Baider, U. Gisi, Y. Aharoni, Naomi Temkin-Gorodeiski, Azica Copel, A. Linn, A. Hagiladi, U. Ravid, Gilly Zimand, Lea Valinsky, Y. Elad, I. Chet, H. Catz, D. Bet-Din, S. Droby, Y. Gadasi, A. Daus, Lea Cohen, Batia Weiss, Batia Horev, Laura Chalopowicz, D. Timar, E. Chalutz, D. Robin, Y. Sachs, G. Forer, M. Lazare, D. Gerling, M. Guershon, Tirza U. Stern, H. Bar, A. Weinberg, M. Perlsman, M. Zeidan, H. Czosnek, M. J. Berlinger, Sara Leibush-Mordechai, Neta Mor, Devora Fridja, I. Ishaaya, Zmira Mendelson, A. R. Horowitz, D. Veierov, N. Aharonson, E. Kletter, Miriam Eliyahu, Annie Fenigstein, G. Bloch, and D. Wool
- Subjects
Agroforestry ,Agriculture ,business.industry ,Insect Science ,Field (Bourdieu) ,Ecology (disciplines) ,Ornamental plant ,Plant Science ,Biology ,business - Published
- 1993
6. Characterization and Reclassification of Yeasts Used for Biological Control of Postharvest Diseases of Fruits and Vegetables
- Author
-
C. L. Wilson, C. P. Kurtzman, W. F. Fett, E. Chalutz, S. F. Osman, and Mclaughlin Randy J
- Subjects
food.ingredient ,Ecology ,biology ,Biological pest control ,food and beverages ,Mycology ,biology.organism_classification ,complex mixtures ,Applied Microbiology and Biotechnology ,Yeast ,food ,Fruits and vegetables ,Penicillium ,Botany ,Debaryomyces hansenii ,Postharvest ,Food science ,Food Science ,Biotechnology ,Mannan ,Botrytis - Abstract
In previous studies workers have shown that three yeast strains (strains US-7, 82, and 101) have biological control activity against various postharvest fungal pathogens of fruits and vegetables, including Penicillium rots of apples and citrus and Botrytis rot of apples. In these reports the researchers have described these strains as Debaryomyces hansenii (anamorph, Candida famata ) or Candida sp. strains. In this study we performed additional physiological, DNA reassociation, and mannan characterization tests that clearly established a new taxonomic classification for these strains, Candida guilliermondii. We also propose amendment of the physiological test profile in the taxonomic description of C. guilliermondii.
- Published
- 1990
7. The expression of a grapefruit gene encoding an isoflavone reductase-like protein is induced in response to UV irradiation
- Author
-
A, Lers, S, Burd, E, Lomaniec, S, Droby, and E, Chalutz
- Subjects
Citrus ,DNA, Complementary ,Base Sequence ,DNA, Plant ,Ultraviolet Rays ,Molecular Sequence Data ,Intracellular Signaling Peptides and Proteins ,Gene Expression Regulation, Enzymologic ,Immunity, Innate ,Blotting, Southern ,Gene Expression Regulation, Plant ,Amino Acid Sequence ,Cloning, Molecular ,Carrier Proteins ,Oxidoreductases ,Sequence Alignment ,Plant Proteins - Abstract
Exposure of harvested grapefruit to UV-C (254 nm) irradiation was previously found to induce resistance against the green mold decay caused by Penicillium digitatum. In order to gain insight into the mechanism of this UV-induced resistance we initiated a study for isolation of genes induced during this process. Using the differential display method we cloned cDNA representing an mRNA which is accumulated in grapefruit peel upon UV irradiation. Sequence analysis revealed that this cDNA represents a gene encoding for an isoflavone reductase-like protein and was termed IRL (isoflavone reductase-like). The grapefruit IRL protein sequence has high homology also to a novel family of other isoflavone reductase-like proteins present in few non-legume plants and whose function is not clear yet. The UV dose, and time following it, which lead to maximal accumulation of the IRL transcript were found to be similar to those leading to maximal induced resistance. The expression of the IRL gene was demonstrated to be induced also by wounding and pathogen infection.
- Published
- 1998
8. Biological Control of Postharvest Diseases of Fruits and Vegetables Through Manipulation of Epiphytic Plant Microflora
- Author
-
E. Chalutz and C.L. Wilson
- Subjects
Host resistance ,business.industry ,Microorganism ,fungi ,Biological pest control ,food and beverages ,Pesticide ,Biology ,biology.organism_classification ,Biotechnology ,Horticulture ,Fruits and vegetables ,Postharvest ,Epiphyte ,business ,Bacteria - Abstract
The opportunity exists to biologically control plant pathogens by manipulating the epiphytic microflora on plant surfaces. Epiphytic populations can be modified by changing environmental conditions such as the nutrient milieu, or by introducing antagonistic microorganisms. We have studied control of postharvest diseases of fruits and vegetables using naturally occurring antagonistic yeasts and bacteria. Antagonistic microorganisms appear to be exceptionally effective as biological control agents in the postharvest environment because they can be targeted where they are needed and the environmental conditions required for high efficacy can be controlled. Effective antagonists may inhibit postharvest pathogens by the production of antibiotics, by successfully competing with the pathogens for nutrients and space, by inducing host resistance, and by interacting directly with the pathogen. Biological control of postharvest diseases by the use of non-antibiotic-producing antagonists may provide an effective and safe alternative to synthetic pesticides for the control of postharvest diseases of fruits and vegetables.
- Published
- 1990
9. Postharvest Biocontrol of Green and Blue Mold and Sour Rot of Citrus Fruit by Debaryomyces hansenii
- Author
-
E. Chalutz and C. L. Wilson
- Subjects
Penicillium digitatum ,biology ,Inoculation ,Blue mold ,food and beverages ,Plant Science ,biology.organism_classification ,Penicillium italicum ,Horticulture ,medicine.drug_formulation_ingredient ,Rutaceae ,Debaryomyces hansenii ,Botany ,Postharvest ,medicine ,Agronomy and Crop Science ,Fruit tree - Abstract
(...)The lemon isolate of D.h. inhibited green mold on grapefruit more effectively than did any of eight other isolates of the same species. Efficacy of D.h. was mainained when applied simultaneously or prior to inoculation with P. digitatum. Efficacy was reduced when D. h. was applied after inoculation. Control of green mold of grapefruit was maintained for 21 days at 11 or 22°C. The yeast antagonist also reduced the incidence of green mold decay of injured, naturally infected grapefruit stored at 11°C for 21 days. D.h. did not inhibit the growth in culture of P. digitatum, P. italicum or G. candidum. A culture filtrate of the yeast antagonist failed to provide any protection against green mold of grapefruit. It may be that D.h. inhibits the pathogens by a mode of action other than antibiotic production
- Published
- 1990
10. Abstracts of papers presented at the 6th Congress of the Phytopathological Society of Israel
- Author
-
A. Bahat, H. D. Ravinovitch, Susan LouriÉ, U. Brodny, U. Afek, F. Lumbroso, Ruth Mkirovich, M. Roytfarb, Ruth Meirovich, Batia Gok, G. Zauberman, Y. Fuchs, A. L. Jones, E. Farkas, M. Bar-Joseph, Y. Sherman, Abraham Sztejnberg, Mona Yulius, Y. Ben-Yephet, O. Ziv, A. Apelbaum, U. Kafkafi, H. Alon, Jaacov Katan, I. Chet, D. Netzer, G. Loebenstein, A. Grinstein, Y. Sachs, G. Ein-Gedi, D. Yeger, Y. Levy, Nurit Zaltz, Y. Eshel, L. V. Edgington, G. Kritzman, D. Rubin, B. Bar-Yosef, D. Zutra, A. Abdul-Razik, G. Salus, G. Fishler, G. A. Strobel, Y. Slonim, G. Mschbeck, A. Dinoor, Rachel Karadavid, J. Manistersky, S. Ovadia, Rivka Barkai-Golan, Y. Hadar, R. Kenneth, M. Dudaii, A. Segal, Yigal Cohen, O. Zeydan, Y. Ofer, Ts. Sandu, S. Marco, Z. Madar, M. Katchansky, J. Krikun, Y. Chen, J. Rotem, Y. Okon, Y. Henis, Y. Elad, Y. Mahrer, G. Baduiah, Mina Schiffmann-Nadel, R. L. Wain, E. Chalutz, R. Jacobsohn, M. B. Brown, E. Lumbroso, Z. Frank, A. Nachmias, Gaby Elal, M. Ressissi, S. Elisha, Y. Spiegel, Y. Epstein, Y. Finkel, Y. Dvash, E. Siti, Z. R. Frank, H. Yunes, Y. Bashan, Talma Katan, Y. Kaspi, B. Meir, J. M. Sacks, H. Frankel, Ilana Gelernter, E. Cohn, Y. Pinkas, Esther Hadar, D. Orion, I. Wahl, Sara Zimmerman-Gries, Edna Tanne, M. Reuveni, D. Sandler, S. Cohen, A. Greenberger, U. Zisman, Naomi Temkin-Gorodeiski, D. Prusky, Z. Arenstein, Y. Oren, F. Shabi, Orly Balasha, I. Ohali, T. Sultan, B. Sneh, Z. Eyal, Z. Solel, M. Levi, Z. Gerstl, Z. Soliel, I. Arad, I. Barash, and J. Daniel
- Subjects
Insect Science ,Library science ,Plant Science ,Biology - Published
- 1979
11. Abstracts of Papers Presented at The Bat-Sheva Seminar on Host — Fungus Interaction
- Author
-
A. M. Mayer, Y. Henis, J. G. H. Wessels, Talma Katan, Y. Koltin, Miriam M. L. So, B. Sneh, Meira Ichielevich-Auster, I. Shomer, M. S. Manocha, R. Balasubramanian, M. H. A. J. Joosten, P. J. G. M. De Wit, R. E. Niks, Paola Bonfante-Fasolo, J. Krikun, J. H. Haas, Sally E. Smith, F. Andrew Smith, J. Friedman, Anita S. Hutchins, D. Perry, Varda Kagan-Zur, Dvira Livne, Nurit Roth-Bejerano, Miriam M. L. SO, N. T. Keen, D. Kobayashi, S. Tamaki, P. Albersheim, P. Bucheli, Felice Cervone, A. Darvill, Giulia De Lorenzo, S. Doares, M. Hahn, R. O’Neill, Margalith Galun, I. Chet, H. R. Hohl, Sylvia Balsiger, M. Odermatt, Chantal Guggenbuehl, Leah Tsror, A. Nachmias, M. Perombelon, Z. Barak, I. Barash, G. Strubel, D. Kenfield, F. Sugawara, Y. Elad, Hanne VolpLn, Virginia Buchner, Y. Burstein, S. Nemec, B. Doneche, U. Matern, Hilke Wendorff, Daria Hamerski, E. Chalutz, S. Droby, C. L. Wilson, P. Ricci, Ph. Bonnet, J. C. Devergne, M. Bruneteau, J. C. Pernollet, F. Panabieres, F. Trentin, D. L. Gutnick, S. Loya, S. Bauer, Y. Aharonowitz, B. Moerschbacher, J. S. Ellis, P. Keenan, J. Friend, G. Wenzel, H. S. Chawla, F. Kohler, R. Schuchmann, Bärbel Foroughi-Wehr, J. Kuć, Mirjam Zilberstein, Y. Pinkas, J. KUć, Y. Cohen, Helena Eyal, J. Hanania, Z. Malik, R. N. Strange, Christine Edwards, Susan Richards, S. Ben-Yehoshua, S. Carmeli, B. Shapiro, Y. Sharoni, Y. Kashman, J. J. Kim, R. Moran, R. Cohen, J. Riov, N. Lisker, J. Katan, J. B. Heale, Ruth Bowen, Sara Movahedi, E. Roebroeck, R. Hoffman, K. Hahlbrock, D. Prusky, M. J. Butler, G. Lazarovits, Verna J. Higgins, R. N. Coo Ley, C. E. Caten, F. C. H. Franklin, R. K. Shaw, R. Reuveni, M. Shimoni, Z. Karchi, Beate Cuypers, Karin Hinze, E. Kombrink, E. Schmelzer, Orly Balass, R. ShapLra, A. B. Oppenheim, Y. Gafni, Y. Ophir, Shulamit Manulis, E. Epstein, Ellen Clark, D. E. Carling, S. Kuninaga, R. H. Leiner, S. Gold, M. Roberson, W. Fischer, P. Schweizer, U. Christ, E. Mösinger, K. Kovats, G. Baer, A. Binder, R. Fluhr, N. Shani, Y. Eyal, Tami Lotan, Yael Shemla, B. Q. Manicom, M. Bar-Joseph, A. Rosner, Hillela Vigodsky-Haas, and J. M. Kotze
- Subjects
Ecology ,Host (biology) ,Insect Science ,Ecology (disciplines) ,Physiology ,Plant Science ,Fungus ,Biology ,biology.organism_classification - Published
- 1988
12. Fermentative production of ethylene by Penicillium digitatum from citrus fruit peel
- Author
-
I. Chet, Esther Kapulnik, and E. Chalutz
- Subjects
Penicillium digitatum ,Ethylene ,Food industry ,biology ,business.industry ,Starch ,food and beverages ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Microbiology ,Industrial waste ,chemistry.chemical_compound ,chemistry ,Penicillium ,Fermentation ,Food science ,business ,Biotechnology ,Citrus fruit - Abstract
Fermentative conditions for the production of ethylene by the fungus Penicillium digitatum during its growth on citrus fruit peel — the waste product of the citrus juice industry — were studied and optimized for maximum production.
- Published
- 1983
13. Relationship among Ventilation of Citrus Storage Room, Internal Fruit Atmosphere, and Fruit Quality
- Author
-
J. Waks, E. Chalutz, Mina Schiffmann-Nadel, and Ella Lomeniec
- Subjects
Genetics ,Horticulture - Abstract
Changes in air composition of the citrus storage atmosphere and of the internal atmosphere of the fruit as affected by the ventilation rate were studied using 1 grapefruit and 2 orange cultivars. These changes were examined in relation to fruit weight loss, ethanol content of the juice, and rot development during storage periods of up to 5 months. Rates of ventilation affected the CO2 concentrations more than the O2 levels of both the external and internal atmospheres of the fruit. In small-scale tests, ventilation rates as low as 10%·hr−1 of the empty volume of the storage space did not cause major changes in the gas composition, nor did they effect fruit quality adversely. In commercial tests, however, an increased rate of ventilation (70% to 100%·hr−1) was needed to reach similar results. On the basis of this information we recommend reducing the ventilation rate in commercial citrus storage rooms from 150% or 200%·hr−1, the rate now commonly employed, to 100%·hr−1. This reduced ventilation rate will help lower costs of refrigeration, while maintaining good fruit quality.
- Published
- 1985
14. The Relationship Between the Production of Ethylene by Certain Fungi, Their Enzyme Constitution, and Their Ability to Accumulate Intracellular Phosphate
- Author
-
Autar K. Mattoo, I. Chet, Esther Kapulnik, and E. Chalutz
- Subjects
Penicillium digitatum ,Growth medium ,Phosphatase ,Acid phosphatase ,Dehydrogenase ,General Medicine ,Biology ,biology.organism_classification ,Phosphate ,Malate dehydrogenase ,chemistry.chemical_compound ,chemistry ,Biochemistry ,biology.protein ,Pyruvate kinase - Abstract
Summary An ethylene-producing isolate of a wild type of Penicillium digitatum was compared to a non-ethylene-producing isolate of this fungus with regard to various biochemical parameters. The intracellular acid-soluble phosphate content was markedly higher in the non-ethylene-producing isolate and in several other non-ethylene-producing fungi than in the ethylene-producing isolate whether cultures were grown in medium containing high (100 mM) or low (0.1 mM) phosphate. Ethylene production by the ethylene-producing isolate increased markedly in low phosphate growth medium and correlated with an increase in acid phosphatase activity but not with changes observed in the activities of glucose-6-phosphate dehydrogenase, pyruvate kinase, malate dehydrogenase or succinate dehydrogenase. However, these latter enzymatic activities were significantly different in the two isolates when cultivated in high phosphate medium. The data indicated that the ability of the fungi to produce ethylene may be related to high phosphatase activity and to their capacity to maintain low phosphate intracellularly.
- Published
- 1983
15. Fumigation of citrus fruit with ethylene dibromide: Desorption of residues and ethylene evolution
- Author
-
E. Chalutz and E. Alumot
- Subjects
Ethylene ,genetic structures ,Chemistry ,Ethylene Dibromide ,Fumigation ,food and beverages ,Applied Microbiology and Biotechnology ,eye diseases ,Horticulture ,chemistry.chemical_compound ,Reaction rate constant ,Agronomy ,Desorption ,sense organs ,Citrus fruit - Abstract
The desorption of ethylene dibromide (EDB) residues from fumigated Shamouti citrus fruits is fitted by a single exponential equation at 17 and 22°C, and by an equation with a double exponential term at 5°C. Establishing the rate constant enables calculation of the initial concentration of EDB residues in the peel, thereby obtaining information on conditions during fumigation and on the possibility of peel injury development in the fumigated fruit. Healthy, harvested Shamouti citrus fruit evolve ethylene at a low rate, which is increased by EDB fumigation. Fumigated fruit in which EDB caused peel injury evolved ethylene at a higher rate than fumigated fruit in which peel injuries did not develop. This information could be used for predicting peel injuries and in studies aimed at a better understanding of the processes leading to the development of peel injuries in fumigated citrus fruit.
- Published
- 1972
16. Precooling of Citrus Fruits Prior to Simulated Transport in Ventilated Ships1
- Author
-
E. Chalutz, Mina Schiffmann-Nadel, J. Waks, and F. S. Lattar
- Subjects
Genetics ,Horticulture - Abstract
Precooling at -2°C for 6 - 24 hrs prior to simulated ventilated shipment reduced weight loss of citrus fruit. Weight loss from the fruit was reduced as cooling rate increased. The difference in weight loss between precooled and control fruit was maintained during simulated shipment and after storage. Precooling the fruit to temp below 0°C could adversely affect its quality and should be avoided.
- Published
- 1974
17. Reducing Susceptibility of Grapefruit to Chilling Injury during Cold Treatment
- Author
-
E. Chalutz, J. Waks, and Mina Schiffmann-Nadel
- Subjects
Horticulture - Abstract
With the expected ban on ethylene dibromide fumigation, cold exposure remains the only quarantine treatment for citrus fruit against the Mediterranean fruit fly. Following a cold treatment, ‘Marsh’ grapefruit (Citrus paradisi Macf.) developed chilling injury (Cl), mostly in the form of slight peel pitting on 3% to 10% of the fruit depending on the season and on other factors. There was no difference in the incidence of Cl between fruit treated at 0°C for 10 days or at 2.2° for 16 days as regulations require. The cold treatment also enhanced decay development during long-term storage of the fruit at 11°. Mold rots developed on Cl peel pitting, and their incidence increased from 1.7% to 3.5% during a storage period of 12 weeks. The presence of the fungicide Thiabendazole (TBZ) in the wax coating of the fruit reduced the incidence of Cl by more than 50%. Delayed cooling, i.e., keeping the freshly harvested packed fruit for 6 days at 17°C prior to initiation of cold treatment, reduced the incidence of Cl by the same extent. By combining a TBZ treatment with delayed cooling, the susceptibility of grapefruit to Cl can be reduced, and cold treatment can be practiced with a low risk of Cl and subsequent decay development.
- Published
- 1985
18. Reduction of Chilling Injury in Grapefruit by Thiabendazole and Benomyl during Long-Term Storage1
- Author
-
Mina Schiffmann-Nadel, E. Chalutz, J. Waks, and M. Dagan
- Subjects
Genetics ,Horticulture - Abstract
Postharvest treatments with thiabendazole (TBZ) and benomyl reduced the incidence of chilling injury (Cl) in grapefruit (Citrus paradisi, MacFadyen) as expressed by peel pitting. The effect persisted during prolonged storage at 2, 5 and 8°C. Thiabendazole was more effective than benomyl. The effectiveness of both TBZ and benomyl in water suspension increased when followed by waxing, but the greatest reduction in Cl was obtained with the chemicals incorporated in the wax coating. The effect of TBZ was enhanced by increasing concentration and residues, while the effect of benomyl did not change with concentration. Both chemicals were effective in reducing rots during cold storage. There was a marked increase in the incidence of rots during shelf-life. These rots, primarily of the mold type—Penicillium digitatum Sacc. and P. italicum Wehmer, developed mostly in pits induced by the low storage temperatures.
- Published
- 1975
19. Rhythmicity in cotton seedlings : Rhythmic ethylene production as affected by silver ions and as related to other rhythmic processes
- Author
-
E. Chalutz, J. D. Anderson, and Arnon Rikin
- Subjects
food.ingredient ,Ethylene ,Methionine ,Bentazon ,Phenylalanine ,Stimulation ,Plant Science ,Phenylalanine ammonia-lyase ,Biology ,chemistry.chemical_compound ,food ,chemistry ,Biochemistry ,Darkness ,Genetics ,Biophysics ,Cotyledon - Abstract
Ethylene production by detached cotyledons of cotton (Gossypium hirsutum L.) seedlings grown under cycles of 12 h darkness and 12 h light has been shown to be rhythmic, with a minimum and maximum 4 and 16 h, respectively after the start of the cycle (Rikin, Chalutz and Anderson, 1984, Plant Physiol. 75, 493-495). Treatment with silver ions stimulated the rhythmic ethylene production in both regular and "inverted" cycles (i.e. dark period changed to light period, and vice versa). The rate of the conversion of [3,4-(14)C]methionine into ethylene also followed the stimulation of rhythmic ethylene evolution by silver ions in both regular and inverted cycles, while treatment with aminoethoxyvinylglycine (AVG) decreased this stimulation. Conversion of exogenous 1-aminocyclopropane-1-carboxylic acid (ACC) into ethylene was not affected by silver ions, but was dependent upon the immediate light conditions, regardless of the time in the light-dark cycle, light decreasing and darkness increasing this process. It is concluded that silver ions stimulate the normal rhythmic ethylene production, and this stimulation is regulated at a step prior to the conversion of ACC into ethylene. The rhythmicity in other processes (cotyledon movement, phenylalanine ammonia-lyase activity, resistance to the herbicide 3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide [bentazon]) was not affected by a decrease in the rhythmic changes in ethylene production by AVG or interference in ethylene action by silver ions. Thus, these rhythmic changes were not regulated by the rhythmic changes in ethylene production.
- Published
- 1984
20. Induction of pisatin by ethylene
- Author
-
E, Chalutz and M A, Stahmann
- Subjects
Antifungal Agents ,Ethylenes ,Stimulation, Chemical - Published
- 1969
21. Ethylene-induced Isocoumarin Formation in Carrot Root Tissue
- Author
-
E. Chalutz, J. E. Devay, and E.C. Maxie
- Subjects
Isocoumarin ,Horticulture ,chemistry.chemical_compound ,Ethylene ,chemistry ,Biochemistry ,Physiology ,Inoculation ,Genetics ,food and beverages ,Plant Science ,Articles - Abstract
The concentrations of 3-methyl-6-methoxy-8-hydroxy-3,4-dihydroisocoumarin (MMHD) formed in carrot roots inoculated with certain fungi or treated with indole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, or 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), were related to the amount of ethylene produced by the root tissue. Ethylene applied exogenously in concentrations above 0.3 ppm induced the formation of MMHD in carrot root discs. Continued production of MMHD required the continued presence of ethylene. The amounts of MMHD in the discs were reduced by CO(2), an inhibitor of ethylene action, and by reduction of the partial pressure of ethylene in fungus-inoculated or 2,4,5-T-treated carrot root discs. The results indicate that ethylene is required for the induction of MMHD formation by carrot root tissue.
- Published
- 1969
22. Biological Control of Postharvest Diseases of Fruit: Inhibition Of Botrytis Rot On Apple by an Antagonistic Yeast
- Author
-
Michael Wisniewski, W. Hershberger, Charles L. Wilson, and E. Chalutz
- Subjects
Horticulture ,food.ingredient ,food ,Biological pest control ,Postharvest ,General Medicine ,Biology ,Yeast ,Botrytis - Abstract
As an alternative to fungicides, biological control of postharvest diseases of fruit has recently met with good success with peaches and apples and is an area of great potential. In contrast to previous study, we were particularly interested in finding antagonists that did not produce antibiotics as part of their mode of action. After extensive screening, several yeast and bacteria were identified that exhibited biocontrol of a number of postharvest disease organisms. In particular, the yeast, Debaryomyces hansenii, indicated great potential as a biocontrol agent without exhibiting antibiotic production as a mode of action. It has been recently shown to effectively control decay on citrus caused by Penicillium digitatum, Penicilliim italicum and Geotrichum candidum. The present report is the first to document the use of D. hansenii to control postharvest decay of apples by Botrytis cinerea and present possible inodes of action.To test for biocontrol activity, apples (cv Golden Delicious) ware wounded with a 4 nm cork borer to a depth of 5 mm.
- Published
- 1988
23. Considerations in the Design of Experimental Cold Storage Plants for Perishable Commodities1
- Author
-
E. Chalutz and G Felsenstein
- Subjects
Horticulture - Abstract
We discuss criteria for the design of cold storage facilities for use in research. Factors considered are: determination of the desired accuracy of temperature and relative humidity control, methods of air circulation and fresh air introduction.
- Published
- 1973
24. A Simple Method for Controlled Introduction of Fresh Air into Experimental Cold Storage Rooms1
- Author
-
E. Chalutz, G. Felsenstein, and J. Waks
- Subjects
Horticulture - Abstract
An inexpensive method for accurate control and measurement of fresh air introduction into experimental storage rooms is described.
- Published
- 1973
25. Reduction of Pitting of Grapefruit by Thiabendazole During Long-term Cold Storage1
- Author
-
Mina Schiffmann-Nadel, E. Chalutz, J. Waks, and F. S. Lattar
- Subjects
Horticulture - Abstract
Incorporation of thiabendazole (TBZ) in the wax coating applied to grapefruit significantly reduced the amount of low temp pitting which developed during prolonged storage at 8 and 12°C.
- Published
- 1972
26. The expression of a grapefruit gene encoding an isoflavone reductase-like protein is induced in response to UV irradiation.
- Author
-
Lers A, Burd S, Lomaniec E, Droby S, and Chalutz E
- Subjects
- Amino Acid Sequence, Base Sequence, Blotting, Southern, Citrus enzymology, Citrus immunology, Citrus radiation effects, Cloning, Molecular, DNA, Complementary, DNA, Plant radiation effects, Immunity, Innate radiation effects, Intracellular Signaling Peptides and Proteins, Molecular Sequence Data, Sequence Alignment, Carrier Proteins genetics, Citrus genetics, Gene Expression Regulation, Enzymologic radiation effects, Gene Expression Regulation, Plant radiation effects, Oxidoreductases genetics, Plant Proteins genetics, Ultraviolet Rays
- Abstract
Exposure of harvested grapefruit to UV-C (254 nm) irradiation was previously found to induce resistance against the green mold decay caused by Penicillium digitatum. In order to gain insight into the mechanism of this UV-induced resistance we initiated a study for isolation of genes induced during this process. Using the differential display method we cloned cDNA representing an mRNA which is accumulated in grapefruit peel upon UV irradiation. Sequence analysis revealed that this cDNA represents a gene encoding for an isoflavone reductase-like protein and was termed IRL (isoflavone reductase-like). The grapefruit IRL protein sequence has high homology also to a novel family of other isoflavone reductase-like proteins present in few non-legume plants and whose function is not clear yet. The UV dose, and time following it, which lead to maximal accumulation of the IRL transcript were found to be similar to those leading to maximal induced resistance. The expression of the IRL gene was demonstrated to be induced also by wounding and pathogen infection.
- Published
- 1998
- Full Text
- View/download PDF
27. Influence of CaCl(2) on Penicillium digitatum, Grapefruit Peel Tissue, and Biocontrol Activity of Pichia guilliermondii.
- Author
-
Droby S, Wisniewski ME, Cohen L, Weiss B, Touitou D, Eilam Y, and Chalutz E
- Abstract
ABSTRACT Interactions between CaCl(2), grapefruit peel tissue, Penicillium digitatum, and the yeast antagonist Pichia guilliermondii strain US-7 were investigated. Application of 68 or 136 mM CaCl(2) to grapefruit surface wounds reduced the incidence of green mold caused by Penicillium digitatum by 43 to 52%. In laboratory tests, a cell suspension (10(7) cells/ml) of Pichia guilliermondii containing either 68 or 136 mM CaCl(2) reduced the incidence of green mold from 27 to 3%. In large scale tests, dip application of 136 mM CaCl(2) with US-7 (10(7) cells/ml) significantly decreased the number of wounds infected by Penicillium digitatum. CaCl(2), with or without yeast cells, stimulated ethylene production in grapefruit tissue. Increasing concentrations of CaCl(2) resulted in decreased spore germination and germ tube elongation of Penicillium digitatum. Pectinolytic activity of crude enzyme preparations of Penicillium digitatum was also inhibited by the presence of increasing concentrations of CaCl(2). US-7 exhibited a strong ability to maintain cytosolic Ca(2+) homeostasis at levels that did not exceed 1.4 muM when exposed to 150 mM CaCl(2). On the other hand, strain 114 of Debaryomyces hansenii, which failed to give any protection against infection by Penicillium digitatum, showed reduced capacity to maintain Ca(2+) homeostasis. The effect of calcium in reducing infection of grapefruit wounds by Penicillium digitatum could be due to direct effects on host tissue (making cell walls more resistant to enzymatic degradation) or the pathogen (interfering with spore germination, growth, and inhibition of fungal pectinolytic enzymes). Alternatively, the ability of US-7 to maintain calcium homeostasis may allow it to grow or assist in its competitive ability in a microenvironment that, because of high levels of calcium ions, is inhibitory to growth of the green mold pathogen.
- Published
- 1997
- Full Text
- View/download PDF
28. Are biological antagonists an alternative to synthetic fungicides for preventing postharvest diseases of fruits and vegetables?
- Author
-
Droby S, Cohen L, Wisniewski ME, Wilson CL, and Chalutz E
- Subjects
- Agriculture methods, Ecology, Immunity, Innate physiology, Antibiosis physiology, Food Contamination prevention & control, Fungicides, Industrial adverse effects, Plant Diseases microbiology
- Abstract
In recent years, both the public and health authorities have become increasingly concerned about the presence of pesticides in our food supply and the environment. As a direct result of this mounting concern, research efforts for the development of alternative methods for the control of postharvest diseases of fruits and vegetables have been intensified. Considerable attention has been placed on assessing the potential of the use of biological antagonists as a viable alternative to the use of synthetic fungicides. Naturally occurring microbial antagonists have been shown to control several rot pathogens on diverse commodities. Such antagonists have various modes of action: antibiosis or competition for nutrients and space or both, induction of resistance in the host tissue, and direct interaction with the pathogen. The commercialization of certain antagonists to control postharvest decay of fruits and vegetables appears to be feasible and may present an alternative to synthetic pesticides.
- Published
- 1996
- Full Text
- View/download PDF
29. Application of Ultraviolet-C Light on Storage Rots and Ripening of Tomatoes.
- Author
-
Liu J, Stevens C, Khan VA, Lu JY, Wilson CL, Adeyeye O, Kabwe MK, Pusey PL, Chalutz E, Sultana T, and Droby S
- Abstract
The application of ultraviolet light (UV-C, 254 nm) hormesis on fruits and vegetables to stimulate beneficial responses is a new method for controlling storage rots and extending the shelf-life of fruits and vegetables. The present study was aimed at treating tomatoes ( Lycopersicon esculentum ) with different UV-C dosages (1.3 to 40 KJ/m
2 ) to induce resistance to black mold ( Alternaria alternata ), gray mold ( Botrytis cinerea ), and Rhizopus soft rot ( Rhizopus stolonifer ). These diseases were effectively reduced when tomatoes were inoculated following UV-C irradiation. UV-C treated tomatoes were firmer in texture and less red in color than the control tomatoes, indicating a delay in ripening. Slower ripening and resistance to storage rots of tomatoes are probably related. The positive effect of UV-C on tomatoes decreased as treatments were performed at stages of increased ripeness.- Published
- 1993
- Full Text
- View/download PDF
30. Characterization and reclassification of yeasts used for biological control of postharvest diseases of fruits and vegetables.
- Author
-
McLaughlin RJ, Wilson CL, Chalutz E, Kurtzman CP, Fett WF, and Osman SF
- Abstract
In previous studies workers have shown that three yeast strains (strains US-7, 82, and 101) have biological control activity against various postharvest fungal pathogens of fruits and vegetables, including Penicillium rots of apples and citrus and Botrytis rot of apples. In these reports the researchers have described these strains as Debaryomyces hansenii (anamorph, Candida famata) or Candida sp. strains. In this study we performed additional physiological, DNA reassociation, and mannan characterization tests that clearly established a new taxonomic classification for these strains, Candida guilliermondii. We also propose amendment of the physiological test profile in the taxonomic description of C. guilliermondii.
- Published
- 1990
- Full Text
- View/download PDF
31. Membrane association and some characteristics of the ethylene forming enzyme from etiolated pea seedlings.
- Author
-
Mattoo AK, Achilea O, Fuchs Y, and Chalutz E
- Subjects
- Cell Membrane enzymology, Kinetics, Lyases isolation & purification, Lyases metabolism, Plants enzymology
- Published
- 1982
- Full Text
- View/download PDF
32. Influence of enol ether amino acids, inhibitors of ethylene biosynthesis, on aminoacyl transfer RNA synthetases and protein synthesis.
- Author
-
Mattoo AK, Anderson JD, Chalutz E, and Lieberman M
- Abstract
The analogs of rhizobitoxine, aminoethoxyvinylglycine (AVG) (l-2-amino-4-2'-aminoethoxy-trans-3 butenoic acid) and methoxyvinylglycine (MVG) (l-2-amino-4-methoxy-trans-3-butenoic acid), that are potent inhibitors of ethylene biosynthesis at 0.1 millimolar also inhibited protein synthesis and charging of tRNA especially at 1 millimolar and higher concentrations. The saturated analog of MVG inhibited ethylene synthesis while the saturated analog of AVG did not. Both saturated AVG and MVG inhibit methionyl- and leucyl-amino acyl-tRNA synthetase. Because of the inhibition of amino acid metabolism in plant tissues by these rhizobitoxine analogs caution is advised in interpreting the results obtained with concentrations of compounds above 0.1 millimolar.
- Published
- 1979
- Full Text
- View/download PDF
33. Rhythmicity in cotton seedlings : Rhythmic ethylene production as affected by silver ions and as related to other rhythmic processes.
- Author
-
Rikin A, Chalutz E, and Anderson JD
- Abstract
Ethylene production by detached cotyledons of cotton (Gossypium hirsutum L.) seedlings grown under cycles of 12 h darkness and 12 h light has been shown to be rhythmic, with a minimum and maximum 4 and 16 h, respectively after the start of the cycle (Rikin, Chalutz and Anderson, 1984, Plant Physiol. 75, 493-495). Treatment with silver ions stimulated the rhythmic ethylene production in both regular and "inverted" cycles (i.e. dark period changed to light period, and vice versa). The rate of the conversion of [3,4-(14)C]methionine into ethylene also followed the stimulation of rhythmic ethylene evolution by silver ions in both regular and inverted cycles, while treatment with aminoethoxyvinylglycine (AVG) decreased this stimulation. Conversion of exogenous 1-aminocyclopropane-1-carboxylic acid (ACC) into ethylene was not affected by silver ions, but was dependent upon the immediate light conditions, regardless of the time in the light-dark cycle, light decreasing and darkness increasing this process. It is concluded that silver ions stimulate the normal rhythmic ethylene production, and this stimulation is regulated at a step prior to the conversion of ACC into ethylene. The rhythmicity in other processes (cotyledon movement, phenylalanine ammonia-lyase activity, resistance to the herbicide 3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide [bentazon]) was not affected by a decrease in the rhythmic changes in ethylene production by AVG or interference in ethylene action by silver ions. Thus, these rhythmic changes were not regulated by the rhythmic changes in ethylene production.
- Published
- 1985
- Full Text
- View/download PDF
34. Methionine-induced Ethylene Production by Penicillium digitatum.
- Author
-
Chalutz E and Lieberman M
- Abstract
Shake cultures, in contrast to static cultures of Penicillium digitatum grown in liquid medium, were induced by methionine to produce ethylene. The induction was concentration-dependent, and 7 mM was optimum for the methionine effect. In the presence of methionine, glucose (7 mM) enhanced ethylene production but did not itself induce ethylene production. The induction process lasted several hours, required the presence of viable mycelium, exhibited a lag period for ethylene production, and was effectively inhibited by cycloheximide and actinomycin D. Thus, the methionine-induced ethylene production appeared to involve induction of an enzyme system(s). Methionine not only induced ethylene production but was also utilized as a substrate since labeled ethylene was produced from [(14)C]methionine.Following induction by the fungus, filtrates of induced shake cultures also evolved ethylene in increasing amounts by both enzymic and monenzymic reactions. Tracer experiments indicated that the ethylene released by the filtrate was derived from a fungal metabolite of methionine and not directly from methionine.
- Published
- 1977
- Full Text
- View/download PDF
35. Characterization of the Phosphate-mediated Control of Ethylene Production by Penicillium digitatum.
- Author
-
Mattoo AK, Chalutz E, Anderson JD, and Lieberman M
- Abstract
Characterization of the phosphate effect on ethylene production by Penicillium digitatum is reported. A low level of phosphate (0.001 millimolar) was about 200 to 500 times as effective as a high phosphate level (100 millimolar) in stimulating ethylene production and the stimulation was readily reversed by addition of phosphate. This phosphate effect did not operate in static cultures. The precursor of ethylene in the stimulated low phosphate system was glutamate but not alpha-ketoglutarate, which is a precursor in static systems. Actinomycin D and cycloheximide effectively inhibited the low phosphate/high ethylene-producing system. Alkaline phosphatase and protein kinase activities were higher in low than in high phosphate systems. We suggest that phosphate level regulates ethylene production by P. digitatum and that the regulation involves a phosphorylation or dephosphorylation reaction of some enzyme system associated with ethylene production. Phosphate-mediated control of ethylene production may also involve the transcriptional and translational machinery of the fungal cell. P. digitatum apparently can produce widely different levels of ethylene by different pathways, depending on culture conditions under which it is grown.
- Published
- 1979
- Full Text
- View/download PDF
36. Enhancement by ethylene of cellulysin-induced ethylene production by tobacco leaf discs.
- Author
-
Chalutz E, Mattoo AK, Solomos T, and Anderson JD
- Abstract
Cellulysin-induced ethylene production in tobacco (Nicotiana tabacum L.) leaf discs was enhanced several-fold by prior exposure of the leaf tissue to ethylene. This enhancement in the response of the tissue to Cellulysin increased rapidly during 4 and 8 hours of pretreatment with ethylene and resulted from greater conversion of methionine to ethylene. On treatment with Cellulysin, the content of 1-aminocyclopropane-1-carboxylic acid (ACC) in leaf discs not pretreated with ethylene markedly increased while that of the ethylene-pretreated tissue was only slightly higher than in the tissue incubated in the absence of Cellulysin. Ethylene-treated tissue, however, converted ACC to ethylene at a faster rate than air controls. These data indicate that ethylene stimulates Cellulysin-induced ethylene production by stimulating the conversion of ACC to ethylene. Data are also presented on a possible relation of this phenomenon to ethylene produced by the tobacco leaf upon interaction with its pathogen, Alternaria alternata.
- Published
- 1984
- Full Text
- View/download PDF
37. Rhythmicity in ethylene production in cotton seedlings.
- Author
-
Rikin A, Chalutz E, and Anderson JD
- Abstract
Cotyledons of cotton (Gossypium hirsutum L.) seedlings grown under a photoperiod of 12 hour darkness and 12 hour light showed daily oscillations in ethylene evolution. The rate of ethylene evolution began to increase toward the end of the dark period and reached a maximum rate during the first third of the light period, then it declined and remained low until shortly before the end of the dark period. The oscillations in ethylene evolution occurred in young, mature, and old cotyledons (7 to 21 day old). These oscillations in ethylene evolution seemed to be endogenously controlled since they continued even when the photoperiod was inverted. Moreover, in continuous light the oscillations in ethylene evolution persisted, but with shorter intervals between the maximal points of ethylene evolution. In continuous darkness the oscillations in ethylene evolution disappeared. The conversion of [3,4-(14)C]methionine into [(14)C] ethylene followed the oscillations in ethylene evolution in the regular as well as the inverted photoperiod. On the other hand, the conversion of applied 1-aminocyclopropane-1-carboxylic acid into ethylene did not follow the oscillations in ethylene evolution, but was affected directly by the light conditions. Always, light decreased and darkness increased the conversion of applied 1-aminocyclopropane-1-carboxylic acid into ethylene. It is concluded that in the biosynthetic pathway of ethylene the conversion of 1-aminocyclopropane-1-carboxylic acid into ethylene is directly affected by light while an earlier step is controlled by an endogenous rhythm.
- Published
- 1984
- Full Text
- View/download PDF
38. Inhibition of Ethylene Production in Penicillium digitatum.
- Author
-
Chalutz E and Lieberman M
- Abstract
Production of ethylene by static cultures of Penicillium digitatum, which utilize glutamate and alpha-ketoglutarate as ethylene precursors, was inhibited by methionine, methionine sulfoxide, methionine sulfone, and methionine sulfoximine. Rhizobitoxine did not affect ethylene production but its ethoxy and methoxy analogues were effective inhibitors of ethylene production; its saturated methoxy analogue and kainic acid stimulated ethylene production. Tracer studies showed that the inhibitors blocked the conversion of [(3)H]glutamate into [(3)H]ethylene.In shake cultures of this fungus, which utilize methionine as the ethylene precursor, rhizobitoxine and its unsaturated analogues all inhibited, while the saturated methoxy analogue stimulated ethylene production. In both types of cultures inhibition was irreversible and was diminished by increasing concentrations of the ethylene precursor. The inhibitory activity or lack of it by rhizobitoxine and its analogues appears to be a function of their structural resemblance to glutamate and methionine as well as of their size and stereoconfiguration. These data suggest similarities between the ethylene-forming system in the fungus and in higher plants despite differences in precursors under some cultural conditions.
- Published
- 1978
- Full Text
- View/download PDF
39. Ethylene-induced Isocoumarin Formation in Carrot Root Tissue.
- Author
-
Chalutz E, Devay JE, and Maxie EC
- Abstract
The concentrations of 3-methyl-6-methoxy-8-hydroxy-3,4-dihydroisocoumarin (MMHD) formed in carrot roots inoculated with certain fungi or treated with indole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, or 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), were related to the amount of ethylene produced by the root tissue. Ethylene applied exogenously in concentrations above 0.3 ppm induced the formation of MMHD in carrot root discs. Continued production of MMHD required the continued presence of ethylene. The amounts of MMHD in the discs were reduced by CO(2), an inhibitor of ethylene action, and by reduction of the partial pressure of ethylene in fungus-inoculated or 2,4,5-T-treated carrot root discs. The results indicate that ethylene is required for the induction of MMHD formation by carrot root tissue.
- Published
- 1969
- Full Text
- View/download PDF
40. Induction of pisatin by ethylene.
- Author
-
Chalutz E and Stahmann MA
- Subjects
- Stimulation, Chemical, Antifungal Agents biosynthesis, Ethylenes pharmacology
- Published
- 1969
41. Ethylene-induced Phenylalanine Ammonia-Lyase Activity in Carrot Roots.
- Author
-
Chalutz E
- Abstract
Ethylene enhanced the activity of phenylalanine ammonialyase in carrot (Daucus carota L., var. "Nauty") root tissue. Slight increase in enzyme activity was exhibited by root discs incubated in ethylene-free air. It was probably due to the ethylene formed within the sliced tissue. Addition of ethylene to the air stream increased phenylalanine ammonia-lyase activity and the total protein content of the discs until maximum activity was reached after 36 to 48 hours of incubation. The continuous presence of ethylene was required to maintain high level of activity. Ethylene, at a concentration of 10 microliter per liter induced higher activity than at lower or higher concentrations. CO(2) partially inhibited the ethylene-induced activity. Cycloheximide or actinomycin D effectively inhibited the ethylene-induced activity in discs that had not previously been exposed to ethylene. The results appear to support the hypothesis that the mode of action of ethylene may involve both de novo synthesis of the enzyme protein and protection or regulation of activity of the induced enzyme.
- Published
- 1973
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.