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Snow chemistry across Antarctica
- N. Bertler, P.A. Mayewski, A. Aristarain, P. Barrett, S. Becagli, R. Bernardo, S. Bo, Xiao C., M. Curran, Qin D., D. Dixon, F. Ferrona, H. Fischer, M. Frey, M. Frezzotti, F. Fundel, C. Genthon, R. Gragnani, G. Hamilton, M. Handley, S. Hong, E. Isaksson, Kang J., Ren J., K. Kamiyama, S. Kanamori, E. Kärkäs, L. Karlöf, S. Kaspari, K. Kreutz, E. Meyerson, A. Kurbatov, Y. Ming, Zhang M., H. Motoyama, R. Mulvaney, H. Oerter, E. Osterberg, M. Proposito, A. Pyne, U. Ruth, J. Simões, B. Smith, S. Sneed, K. Teinilä, F. Traufetter, R. Udisti, A. Virkkula, O. Watanabe, B. Williamson, J-G. Winther, Li Y., E. Wolff, Li Z., A. Zielinski
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- Journal:
- Annals of Glaciology / Volume 41 / 2005
- Published online by Cambridge University Press:
- 14 September 2017, pp. 167-179
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An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO3, SO4) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve our understanding of the fundamental factors that ultimately control the chemistry of snow or ice samples. This paper aims to initiate data compilation and administration in order to provide a framework for facilitation of Antarctic-wide snow chemistry discussions across all ITASE nations and other contributing groups. The data are made available through the ITASE web page (http://www2.umaine.edu/itase/content/syngroups/snowchem.html) and will be updated with new data as they are provided. In addition, recommendations for future research efforts are summarized.
Contributors
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- By Graeme J.M. Alexander, Heung Bae Kim, Michael Burch, Andrew J. Butler, Tanveer Butt, Roy Calne, Edward Cantu, Robert B. Colvin, Paul Corris, Charles Crawley, Hiroshi Date, Francis L. Delmonico, Bimalangshu R. Dey, Kate Drummond, John Dunning, John D. Firth, John Forsythe, Simon M. Gabe, Robert S. Gaston, William Gelson, Paul Gibbs, Alex Gimson, Leo C. Ginns, Samuel Goldfarb, Ryoichi Goto, Walter K. Graham, Simon J.F. Harper, Koji Hashimoto, David G. Healy, Hassan N. Ibrahim, David Ip, Fadi G. Issa, Neville V. Jamieson, David P. Jenkins, Dixon B. Kaufman, Kiran K. Khush, Heung Bae Kim, Andrew A. Klein, John Klinck, Camille Nelson Kotton, Vineeta Kumar, Yael B. Kushner, D. Frank. P. Larkin, Clive J. Lewis, Yvonne H. Luo, Richard S. Luskin, Ernest I. Mandel, James F. Markmann, Lorna Marson, Arthur J. Matas, Mandeep R. Mehra, Stephen J. Middleton, Giorgina Mieli-Vergani, Charles Miller, Sharon Mulroy, Faruk Özalp, Can Ozturk, Jayan Parameshwar, J.S. Parmar, Hari K. Parthasarathy, Nick Pritchard, Cristiano Quintini, Axel O. Rahmel, Chris J. Rudge, Stephan V.B. Schueler, Maria Siemionow, Jacob Simmonds, Peter Slinger, Thomas R. Spitzer, Stuart C. Sweet, Nina E. Tolkoff-Rubin, Steven S.L. Tsui, Khashayar Vakili, R.V. Venkateswaran, Hector Vilca-Melendez, Vladimir Vinarsky, Kathryn J. Wood, Heidi Yeh, David W. Zaas, Jonathan G. Zaroff
- Edited by Andrew A. Klein, Clive J. Lewis, Joren C. Madsen
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- Book:
- Organ Transplantation
- Published online:
- 07 September 2011
- Print publication:
- 11 August 2011, pp vii-x
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ROOT ROT RESISTANCE IN NEW CASSAVA VARIETIES INTRODUCED TO FARMERS IN NIGERIA
- R. U. OKECHUKWU, A. G. O. DIXON, M. O. AKORODA, M. MWANGI, R. BANDYOPADHYAY
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- Journal:
- Experimental Agriculture / Volume 45 / Issue 1 / January 2009
- Published online by Cambridge University Press:
- 01 January 2009, pp. 15-24
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In 2004 and 2005 through field trials in over 2500 locations in several agroecological zones, 40 new cassava varieties were introduced in Nigeria. The trials were managed by scientists, extension workers and farmers. The aim in introducing these new varieties was to pre-emptively manage cassava mosaic disease, to avert an imminent threat from the Ugandan strain of the pathogen and prevent damage to the Nigerian cassava economy. From these trials, 10 new varieties were selected and officially released for high root yield, high dry matter content and acceptability for food, industry and livestock. Cassava root rot is a major source of yield loss in Nigeria, especially where farmers practice late harvest because they wait for a good price from the market before harvest and sales. This paper investigated how the 40 varieties together with three old improved varieties currently in farmers' fields during the formal trials responded to root rot disease. No absolutely resistant variety was found, indicating that early harvest (9–11 months after planting) is still the best way to reduce losses from root rot. Root rot is also significantly (p ≤ 0.05) influenced by genotype and environment interaction. Most root rot was recorded in the humid forest and the least was in the Sudan savanna agroecological zone. Using a rank-sum method, the 43 varieties were separated into highly resistant, resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible classes.
FIELD EVALUATION OF ROOT ROT DISEASE AND RELATIONSHIP BETWEEN DISEASE SEVERITY AND YIELD IN CASSAVA
- T. J. ONYEKA, A. G. O. DIXON, E. J. A. EKPO
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- Journal:
- Experimental Agriculture / Volume 41 / Issue 3 / July 2005
- Published online by Cambridge University Press:
- 15 July 2005, pp. 357-363
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Reports of cassava root rot disease from different African countries have increased in recent times. Field studies were conducted from July 1998 to October 1999 to determine a reproducible disease assessment method that would allow the comparison of results from different locations and an evaluation of the relationship between disease severity and root yield. Single point disease assessments at 6, 9, 12 and 15 months after planting (MAP) were compared to multiple points assessment based on the area under a disease progress curve (AUDPC). Single point assessments at 12 and 15 MAP, and the AUDPC identified continuous variation (p≤0.01) among the genotypes. However, a consistent result across trials was obtained only with the assessment based on AUDPC. Root dry yield (DYLD) at 15 MAP showed a strong negative correlation with AUDPC (r=−0.74). Regression analysis also confirmed the negative relationship between yield and root rot severity. The five genotypes compared were separated into resistant (91/02324, 30572 and 92/0427) and susceptible (92/0057 and TME-1) groups. It was concluded that root rot disease may cause significant yield loss; however, the magnitude of the yield loss will depend on the susceptibility of the cassava genotype.
Environmental stability of iron and zinc concentrations in grain of elite early-maturing tropical maize genotypes grown under field conditions
- S. O. OIKEH, A. MENKIR, B. MAZIYA-DIXON, R. M. WELCH, R. P. GLAHN, G. GAUCH
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- Journal:
- The Journal of Agricultural Science / Volume 142 / Issue 5 / October 2004
- Published online by Cambridge University Press:
- 24 March 2005, pp. 543-551
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Assessment of the stability of micronutrients is important in breeding for the enhanced nutritional quality of staple food crops as a means to alleviate malnutrition. Twenty early-maturing elite tropical maize (Zea mays L.) genotypes were evaluated over 2 years at three locations representing three distinct agroecologies in West and Central Africa (WCA). The objectives were to analyse the pattern of genotype×environment interactions (GEI) and environmental stability of iron and zinc concentrations in grain using the Additive Main Effects and Multiplicative Interaction (AMMI) statistical model. Results indicated that the effects of genotypes, environments and GEI were significant (P<0·05) for both micronutrients. The effect of GEI was about double the contribution of the genotypes for grain iron and more than double the effect of genotypes for grain zinc. Partitioning of GEI indicated that variety×location was the dominant source of a significant amount of GEI for both micronutrients. Scores of the first two interaction principal component axes (IPCA1 and IPCA2) from the AMMI were significant and accounted for 0·68–0·75 of the pattern of GEI for both micronutrients. About half of the genotypes evaluated were stable for grain iron and zinc concentration over the set of environments. The AMMI model identified ACR98TZEMSR-W as the most stable genotype for grain iron and MAKA-SRBC5 was the most stable for grain zinc. However, the yellow genotype, AK94-DMR-ESR-Y was the most promising, with high and moderately stable concentrations of iron and zinc in the grain. Because it is yellow, with beta-carotene content and high concentrations of iron and zinc in the grain, it might significantly contribute to an improved intake of these micronutrients in populations who rely on maize for a major portion of their daily diet.
Looking Backward, Looking Forward: MLA Members Speak
- April Alliston, Elizabeth Ammons, Jean Arnold, Nina Baym, Sandra L. Beckett, Peter G. Beidler, Roger A. Berger, Sandra Bermann, J.J. Wilson, Troy Boone, Alison Booth, Wayne C. Booth, James Phelan, Marie Borroff, Ihab Hassan, Ulrich Weisstein, Zack Bowen, Jill Campbell, Dan Campion, Jay Caplan, Maurice Charney, Beverly Lyon Clark, Robert A. Colby, Thomas C. Coleman III, Nicole Cooley, Richard Dellamora, Morris Dickstein, Terrell Dixon, Emory Elliott, Caryl Emerson, Ann W. Engar, Lars Engle, Kai Hammermeister, N. N. Feltes, Mary Anne Ferguson, Annie Finch, Shelley Fisher Fishkin, Jerry Aline Flieger, Norman Friedman, Rosemarie Garland-Thomson, Sandra M. Gilbert, Laurie Grobman, George Guida, Liselotte Gumpel, R. K. Gupta, Florence Howe, Cathy L. Jrade, Richard A. Kaye, Calhoun Winton, Murray Krieger, Robert Langbaum, Richard A. Lanham, Marilee Lindemann, Paul Michael Lützeler, Thomas J. Lynn, Juliet Flower MacCannell, Michelle A. Massé, Irving Massey, Georges May, Christian W. Hallstein, Gita May, Lucy McDiarmid, Ellen Messer-Davidow, Koritha Mitchell, Robin Smiles, Kenyatta Albeny, George Monteiro, Joel Myerson, Alan Nadel, Ashton Nichols, Jeffrey Nishimura, Neal Oxenhandler, David Palumbo-Liu, Vincent P. Pecora, David Porter, Nancy Potter, Ronald C. Rosbottom, Elias L. Rivers, Gerhard F. Strasser, J. L. Styan, Marianna De Marco Torgovnick, Gary Totten, David van Leer, Asha Varadharajan, Orrin N. C. Wang, Sharon Willis, Louise E. Wright, Donald A. Yates, Takayuki Yokota-Murakami, Richard E. Zeikowitz, Angelika Bammer, Dale Bauer, Karl Beckson, Betsy A. Bowen, Stacey Donohue, Sheila Emerson, Gwendolyn Audrey Foster, Jay L. Halio, Karl Kroeber, Terence Hawkes, William B. Hunter, Mary Jambus, Willard F. King, Nancy K. Miller, Jody Norton, Ann Pellegrini, S. P. Rosenbaum, Lorie Roth, Robert Scholes, Joanne Shattock, Rosemary T. VanArsdel, Alfred Bendixen, Alarma Kathleen Brown, Michael J. Kiskis, Debra A. Castillo, Rey Chow, John F. Crossen, Robert F. Fleissner, Regenia Gagnier, Nicholas Howe, M. Thomas Inge, Frank Mehring, Hyungji Park, Jahan Ramazani, Kenneth M. Roemer, Deborah D. Rogers, A. LaVonne Brown Ruoff, Regina M. Schwartz, John T. Shawcross, Brenda R. Silver, Andrew von Hendy, Virginia Wright Wexman, Britta Zangen, A. Owen Aldridge, Paula R. Backscheider, Roland Bartel, E. M. Forster, Milton Birnbaum, Jonathan Bishop, Crystal Downing, Frank H. Ellis, Roberto Forns-Broggi, James R. Giles, Mary E. Giles, Susan Blair Green, Madelyn Gutwirth, Constance B. Hieatt, Titi Adepitan, Edgar C. Knowlton, Jr., Emanuel Mussman, Sally Todd Nelson, Robert O. Preyer, David Diego Rodriguez, Guy Stern, James Thorpe, Robert J. Wilson, Rebecca S. Beal, Joyce Simutis, Betsy Bowden, Sara Cooper, Wheeler Winston Dixon, Tarek el Ariss, Richard Jewell, John W. Kronik, Wendy Martin, Stuart Y. McDougal, Hugo Méndez-Ramírez, Ivy Schweitzer, Armand E. Singer, G. Thomas Tanselle, Tom Bishop, Mary Ann Caws, Marcel Gutwirth, Christophe Ippolito, Lawrence D. Kritzman, James Longenbach, Tim McCracken, Wolfe S. Molitor, Diane Quantic, Gregory Rabassa, Ellen M. Tsagaris, Anthony C. Yu, Betty Jean Craige, Wendell V. Harris, J. Hillis Miller, Jesse G. Swan, Helene Zimmer-Loew, Peter Berek, James Chandler, Hanna K. Charney, Philip Cohen, Judith Fetterley, Herbert Lindenberger, Julia Reinhard Lupton, Maximillian E. Novak, Richard Ohmann, Marjorie Perloff, Mark Reynolds, James Sledd, Harriet Turner, Marie Umeh, Flavia Aloya, Regina Barreca, Konrad Bieber, Ellis Hanson, William J. Hyde, Holly A. Laird, David Leverenz, Allen Michie, J. Wesley Miller, Marvin Rosenberg, Daniel R. Schwarz, Elizabeth Welt Trahan, Jean Fagan Yellin
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- Journal:
- PMLA / Publications of the Modern Language Association of America / Volume 115 / Issue 7 / December 2000
- Published online by Cambridge University Press:
- 23 October 2020, pp. 1986-2078
- Print publication:
- December 2000
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