[For further information on the Electronic Forum on Biotechnology in Food and
Agriculture see Forum website.
Note, participants are assumed to be speaking on their own behalf, unless they state otherwise.]
Sent: 08 June 2005 13:59
Subject: 16: Introducing biotechnology in rural areas = sausages to a new born baby
I’m DOULDE DARMAN Roger (PhD. Food science and Nutrition), from the Institute of Agricultural Research for Development (IRAD), Cameroon.
I’m still inquiring about the issue and applications of biotechnology tools, such as molecular markers or cryopreservation and reproductive technologies, in the rural areas. Do they need such technology? If yes, is it useful for them? And can they use these "high technologies"? I trust the target group of these new biotechnologies may be those people from rural areas (if urban, we then do not contribute (or little) to alleviate poverty in developing countries, as 75-80% of the poor in developing countries live in the rural areas!). My point is wishing to introduce these new (high???) biotechnological methods in rural areas seems to be “trying to give a big sausage to a new born baby” (i.e. sausage is good for adults but don’t give it to your little baby because it’s good for you!!! Then he can get in trouble and can pass away because of indigestion).
Let me give a practical example with recent work on cassava process. We know cassava (Manihot esculenta Crantz) roots serve as food for more than 800 million people in the tropics. Despite this useful application, two drawbacks limit the utilisation of these roots as human food. These are its low protein content and potential cyanide toxicity. Traditional processing methods used by people in the rural areas to reduce these bottlenecks, always include a typical step of fermentation which occurs spontaneously. We notice that this natural fermentation is plagued with many problems related to its dependence on the chance of inoculation from the environment. These problems include high levels of residual cyanide (100 to 170 ppm), long softening time (4 to 5 days), non-reproducible quality and unhygienic products.
To solve these problems we use some applications of biotechnological methods, as we isolate from dried fermented cassava tubers some microorganisms on the basis of their ability to produce enzymes involved in biochemical and physiochemical phenomena, which occur in cassava natural fermentation and are responsible for the degradation of cyanide compounds and tuber softening (beta-glucosidase, alpha-amylase, pectin hydrolase and polygalacturonase). With the aim of large-scale utilization of this starter culture, selected microorganisms (a lactic acid bacteria identified as Lactobacillus plantarum and a mould identified as Rhizopus oryzae) were dried and used as starter culture for cassava fermentation. The use of these strains as a mix starter culture rapidly softened the roots permitting the reduction of the total cyanide content by about 95±4%. These results, apart from the fact that we published several articles, were not so interesting as they still remain in the laboratory and were never accepted by populations. And, believe me, all effort was made to transmit these findings to the target group (rural peoples) but NO WAY. So, sorry about this, but seems like we waste our time!!!! And my question remains do rural population need such technology? What’s the usefulness of biotechnological methods for rural population?
Dr. DJOULDE DARMAN Roger
B.P 33 Maroua
Email: djoulde (at) gmail.com
[More details on biotechnology for processing of foods, including cassava, can be found from Conference 11 of this Forum (held 14 June to 15 July 2004), entitled "Biotechnology applications in food processing: Can developing countries benefit?" http://www.fao.org/biotech/C11doc.htm ...Moderator].
Sent: 08 June 2005 14:01
Subject: 17: Re: Interspecific hybridization - Cassava
This is Nagib Nassar, Brazil, once again.
I wish to explain some topics related to conservation of crop wild relatives by interspecific hybridization: The case of cassava.
1. Interspecific hybridizations were made using the wild species as a maternal parent. This means that the hybrids maintained the cytoplasm of wild species. Reciprocal crosses in many cases (not in all cases of wild species) are not successful. In the case of Manihot glaziovii, M. pseudoglaziovii, M. dichotoma, M. brachyandra and M. leptophylla, using the wild species as female parent is far more successful than using it as a male.
2. Obtaining interspecific hybrids has been followed by doubling of their chromosome number to restore lost fertility due to chromosome pairing. This stage is as difficult as breaking interspecific barriers because chimera formation is predominant, its instability too.
3. Re-introducing the wild species accompanied by their polyploidized interspecific hybrids probably is the most interesting part of our work. By artificially polyploidizing the interspecific hybrids we imitated what had been done in nature and took millions of years to occur. This part is on what I adressed my participants colleages, and asked their opinion. Details on confirmation of interspecific hybridization using morphological gene markers are found at www.geneconserve.pro.br
Departamento de Genetica e Morfologia,
Instituto de Ciencias Biologicas,
Universidade de Brasilia,
Campus Universitario Darcy Ribeiro, Asa Norte.
CEP: 70910–900, Brasilia – DF,
Phone: (+55.61) 349.3253
Fax: (+55.61) 349.3562
nagnassa (at) rudah.com.br
Sent: 08 June 2005 14:02
Subject: 18: Re: Establishing a universal molecular marker data base
This is from Vijay D., India.
The establishment of a universal molecular marker data base as advocated by Theodore J. Kisha (message 6, June 7) is really a remarkable idea. But before venturing into such development one has to look after certain issues like,
* Selection of a set of universally reliable and reproducible markers
* Consensus on the outcome from different markers
* Standardisation of methodologies including the mode of analysis etc.
Even though a lot of research articles have been published regarding the use of various molecular markers in identifying a biological unit (DNA fingerprinting) and in understanding the diversity through similarity indices, there has been no consensus and no acceptance from international bodies. Thus, the foremost and fundamental issue is to draw a conclusion in the usage of molecular markers rather than continuing the work with different markers in different cultivars by different persons.
D. Vijay, PhD
International Plant Genetic Resources Institute
IPGRI Office for South Asia
NASC complex, Pusa Campus
New Delhi - 110 012, India
E-mail: vijaydunna (at) gmail.com
Sent: 08 June 2005 14:05
Subject: 19: Re: Establishing a universal molecular marker data base
I am Emma Sales of the University of Southern Mindanao, Kabacan, Cotabato, Philipines.
I am glad to learn of this effort. There are already some data base for SSR markers especially in Centre de Cooperation Internationale en Recherche Agronomique pour le Developpement (CIRAD) website. I have visited this website in search of the SSR markers for rubber and cocoa. It seems that, in rubber, no SSR marker is yet available. However in cocoa, markers are published but I cannot access the full sequences of the published markers. Can anyone from this conference tell me how to access the full sequence of those markers? I need them to order from PROLIGO or other companies.
Department of Plant Breeding and Genetics,
University of Southern Mindanao,
ekalaw (at) yahoo.com
[Participants wishing to respond to this specific question about cocoa or rubber simple sequence repeat (SSR) markers should send a message directly to Emma. An SSR marker, also known as a microsatellite, is defined by the FAO biotechnology glossary (http://www.fao.org/biotech/index_glossary.asp?lang=en) as a segment of DNA characterized by a variable number of copies (typically 5-50) of a sequence of around 5 or fewer bases (called a repeat unit). At any one locus (genomic site), there are usually several different "alleles" in a population, each allele identifiable according to the number of repeat units. This existence of multiple alleles (high level of polymorphism) has enabled microsatellites to be developed as powerful markers in many different species. They are detected by the polymerase chain reaction (PCR)...Moderator].
Sent: 08 June 2005 14:11
Subject: 20: Re: Applying biotechnology to livestock - Egypt
I am Pradeepa Silva. A senior lecturer in animal genetics and breeding attached to the Department of Animal Science, University of Peradeniya, Sri Lanka.
I am in total agreement with Mahamoud Abdel Aziz (Message 7, June 7) in his description of the status of animal husbandry in developing countries. With the lapses in the field level, as described in his email, it is difficult to get benefits from applications of biotechnology.
In Sri Lanka, the limited applications of biotechnology we could see in the area of livestock is genetic characterization of indigenous animals other than commonly practiced artificial insemination (AI). The characterization is also not done as a national need but as individual attempts. However, when the animal conservation is considered again it too is not in the national agenda.
In this context, I guess the regional or global level involvement is very much appropriate to make the role of biotechnology more efficient and useful in the conservation of animal and fishery genetic resources in developing countries.
Department of Animal Science
Faculty of Agriculture
University of Peradeniya
pradeepas (at) pdn.ac.lk
Sent: 08 June 2005 15:26
Subject: 21: Re: Low cost options for tissue culture
This is Edo Lin, independent consultant.
I would like to reply to the message posted by Joe Cummins (message 9, June 7) regarding low cost options for tissue culture.
In vitro conservation and regeneration as tools for the conservation of genetic resources has been widely studied and the general consensus seems to be that it provides an appropriate tool. It is especially useful in cases where plants do not produce seeds or seeds which lose their viability when dried down to safe storage moisture levels.
Such plants may be conserved in situ or in field collections but this is not always easy and they are prone to diseases/pests or climatological damages. Ex situ conservation in the form of low-growth tissue culture or cryopreservation may therefore be preferable.
Joe Cummins rightly points out that, due to inherent genetic instability of some plant species, in vitro collections may give rise to somaclonal variation which, in turn, may give rise to increased genetic variation. However, improved protocols as reported by Drew and others overcome these potential problems. Improved protocols are reported for passion fruit, coffee, neem, lychee and papaya.
Engelmann, F. 1998. In vitro conservation of horticultural genetic resources. Review of the state of the art. http://www.agrsci.unibo.it/wchr/wc2/engelman.html
Withers, L.A. and Engels, J.M.M. 1990. The test tube genebank - A safe alternative to field conservation. IPGRI-APO newsletter 3, 1990. http://www.ipgri.cgiar.org/regions/apo/newsletters/news03/index.htm
Drew, R.A. 1997. The application of biotechnology to the conservation and improvement of tropical and subtropical fruit species. http://www.fao.org/ag/agp/agps/pgr/drew1.htm
309, rue de Bombon
tel and fax: +33 164387844
e-mail: lin.edo (at) free.fr
Sent: 08 June 2005 15:49
Subject: 22: Low cost options for tissue culture // Storing DNA
This is E.M. Muralidharan from India. I work for a public funded forestry research organization on tissue culture, genetic transformation and use of molecular markers for forestry crops.
I tend to agree with Joe Cummins (Message 9, June 7) regarding the unsuitability of tissue cultures as a means of conservation. While the use of slow growing shoot cultures may not carry a great risk of variability (consider the fact that the floriculture and horticulture industry depends a lot on micropropagation), other techniques are suspect. Except for purposes of bulking and international exchange of germplasm, tissue culture should not, in my opinion, be used as the major means of conservation of any species. However, it would be useful to undertake studies with molecular markers to understand the extent of the somaclonal variation in slow-growing or cryopreserved cultures to enable decisions to be taken on using the technology as a supplement to traditional methods of preserving germplasm.
While on the subject of supplementing technologies, I wish to get the opinion of participants on the potential for use of DNA (purified and properly stored) as a means of conservation of genetic material for the long-term. Will it be a viable option when we consider that it may serve only as a means of gene prospecting or as a means of resurrecting the plant (à la Jurassic Park !) at some future date?
Dr. E.M. Muralidharan
Kerala Forest Research Institute
Peechi, Thrissur, Kerala 680653
emmurali (at) kfri.org
Sent: 08 June 2005 16:44
Subject: 23: DNA barcodes for identification of plant species
I am PK Gupta, Meerut, India.
During the last few months I have read several articles on DNA barcoding for identification of plants. There are several sequences which are suitable for this purpose. A recent paper in PNAS (June 7) describes some of the work in this area. The conference should have a dialogue in this area for the benefit of those who are unaware of this important area of research.
Honorary Emeritus Professor and INSA Senior Scientist
Molecular Biology Laboratory
Department of Genetics and Plant Breeding
Ch. Charan Singh University
Tel (Lab): 91-121-2768195
TeleFax : 91-121-2768195
e-mail : pkgupta36 (at) vsnl.com, pkgupta36 (at) hotmail.com
[The article referred to in the 7 June 2005 edition of the Proceedings of the National Academy of Sciences of the United States of America (PNAS) is by W.J. Kress et al., entitled "Use of DNA barcodes to identify flowering plants". They propose 2 specific DNA regions that could be used to discriminate between species of flowering plants, concluding that "the sequences in this pair of loci have the potential to discriminate among the largest number of plant species for barcoding purposes". They note that DNA barcodes "show promise in providing a practical, standardized, species-level identification tool that can be used for biodiversity assessment, life history and ecological studies, and forensic analysis". The paper is freely available on-line at http://www.pnas.org/cgi/reprint/102/23/8369 (the e-mail address for correspondence is kressj (at) si.edu) ...Moderator].