While I was working
for the International Livestock Reseacrh Institute, I had a chance to
work with scientists in the area of palnt in vitro culture, breeding
system of plants, and phytochemistry. I managed to
be included in the autorship position due to my contributions in
the scientific investigation. I have two articles which I
published
as first author in local journals in Ethiopia and one article as second
author in an international journal and a working document on
characterization of forage plant genetic resources. Abstracts and links
are provided for some of the articles.
Publications
- Girma Gebremariam, Sileshi Nemomessa, Hanson J. and Abebe
Demissie (2003). Viability and germination of pollen grains of Sesbania
sesban (L.) Merr. Ethiop. J. Biol. Sci. 2 (1). 1-13)
- Girma Gebremariam, Sileshi
Nemomessa, Abebe Demissie and Hanson J. (2002). The mating system of Sesbania sesban
L. Merr. (Leguminosae), SINET, Ethio. J. Sci. 25 (2) 177-190.
- Jess D. Reed, Girma
Gebremariam, Christopher J. Robinson, Jean Hanson, Agnes Odenyo and
Paul M. Treichel (2001). Diamino Butanoic acid, a potential
lathyrogenic amino acid in leaves of Acacia angustissima. J.
Feed Sci. and Techno. 81 (15): 1481-1486).
- Ribu M’ Ribu, Girma Gebremariam
and Hanson J. (1995). In vitro establishment and multiplication
of napier grass (elephant grass, Pennisetum purpureum Schum.)
through shoot tip culture, pp. 11-20. In: In vitro culture and
biochemical characterization of forage genetic resources at
International Livestock Research Institute (ILRI).
Girma
Gebremariam, International Livestock Research Institute (ilri)
Sileshi Nemomissa, Department of Biology, Faculty of Science, Addis
Ababa University
Abebe Demissie, Biodiversity Conservation and Research Institute
Jean Hanson, International Livestock Research Institute (ilri)
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Abstract
The mating system of Sesbania sesban
was studied using one natural population and two cultivated
populations. A large number of progeny (600) was assayed from each
population for one polymorphic locus of Malate dehydrogenase (Mdh). The
level of out-crossing in the studied populations ranged from 40–100%.
The genotype frequencies were in agreement with those of the
Hardy-Weinberg expected genotype proportions as in randomly mating
populations at P < 0.05. The floral structure and the pollen
shedding behaviour of the flowers of S. sesban could favour
cross-pollination and/or self-pollination depending on the
circumstances. Self-pollination usually occurs late in the flowering
period when pollinators fail to visit the flowers. Such a “delayed
selfing” facilitates out-crossing in the presence of appropriate
pollinators under natural conditions, but confers a selective advantage
where pollinators are limiting. The results indicated that S. sesban
could be self-fertilized in the absence of pollinators or could
out-cross with other heterozygous individuals in the neighboring
population when suitable pollinators are available. S. sesban exhibits
“facultative xenogamy” or “delayed selfing” and is a mixed mating
species.
Key words/phrases: Allozymes, delayed selfing, Hardy-Weinberg equilib
rium, malate dehydrogenase, mixed mating system
SINET: Ethiopian Journal of Science Vol.25(2) 2002: 177-190
http://www.ajol.info/viewarticle.php?jid=96&id=8144
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The leaves and flowers of Sesbania
sesban.
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Acetyldiaminobutanoic
acid, a
potential lathyrogenic amino acid in leaves of Acacia
angustissima
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Jess D Reed
1 *,
Girma Gebre-Mariam 2, Christopher J Robinson 2,
Jean Hanson 2, Agnes Odenyo 2, Paul
M Treichel 3
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1Department of Animal Sciences,
University of Wisconsin-Madison, 1675 Observatory Drive, Madison, WI
53706, USA
2International Livestock Research
Institute, PO Box 5689, Addis Ababa, Ethiopia
3Department of Chemistry,
University of Wisconsin-Madison, 1101 University Avenue, Madison, WI
53706, USA
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*Correspondence
to Jess D Reed, Department of Animal Sciences, University of
Wisconsin-Madison,
1675 Observatory Drive, Madison, WI 53706, US
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Key
words: non-protein amino acids; acacia;
lathyrism; cation exchange chromatography; high performance liquid
chromatography; nuclear magnetic resonance
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Abstract:
Acacia angustissima
has potential in agroforestry systems
for forage production in tropical environments. However, feeding trials
indicate that the leaves are potentially toxic. Signs of toxicity in
sheep are similar to those presented by sheep fed flatpea (Lathyrus
sylvestris) hay which contains a high concentration of the
non-protein amino acid 2,4-diaminobutanoic acid (DABA). Cation exchange
chromatography, high-performance liquid chromatography (HPLC) and NMR
were used to isolate and identify the non-protein amino acid in A
angustissima leaves. A quantitative HPLC method was used to
determine the content of the non-protein amino acid in leaves from 20
accessions. The non-protein amino acid was identified as 4-N-acetyl-2,4-diaminobutanoic
acid (ADAB), previously reported to occur in seeds. The average and
range in ADAB content were 16.8 and 10.6-25.4 mg g-1
respectively. This content of ADAB is higher than the levels of DABA in
flatpea hay that are toxic to sheep.
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© 2001
Society of Chemical
Industry
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Received:
15 November 2000; Revised: 14 June 2001; Accepted: 6 August 2001
10.1002/jsfa.960 About DOI
http://www3.interscience.wiley.com/cgi-bin/abstract/86510569/ABSTRACT
 Leaf and flowers of Acacia angustissima
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