Forum Conf 1 (biotech and crop sector)

Below are extracts from an article in one of Kenyan daily newspapers 11 April

Biotechnology: New danger or solution to Africa's food deficit?

"An entire country faces famine. The government calls out for food relief to help stem the death and starvation across. The relief food that is donated is genetically-modified. The government knows this. Should it accept the food or not? Or is this really a rhetorical question?"

"This technology will help fight hunger in Kenya," states agriculture economist Gem Argwings-Kodhek. A senior research fellow at Egerton University's Tegemeo Institute, he says: "The cost of production of commodities will decrease and help protect plants against pests." He sums it up as "High production for little seed input".

"If the whole debate is really just about more people having more food to eat in Africa, in general, and Kenya, in particular, has anybody asked the farmer why she (for, in most cases, it is a she) or he generally produce less and less each year? Why is she or he experiencing famine? The answers to these questions may be surprising."

The last part highlights an important issue, i.e. farmers should be involved in biotechnology development so that their needs are addressed.

Peter Mwangi
Lund University, Sweden
peter.mwangi.507@student.lu.se

[To contribute to this conference, send your message to biotech-room1@mailserv.fao.org For further information on the Electronic Forum on Biotechnology in Food and Agriculture see http://www.fao.org/biotech/forum.asp ]

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 10:33 AM
To: 'biotech-room1@mailserv.fao.org'
Subject: Re: pest res. to Bt / GM and human health

Ms Salzman [10 April] makes a sound point about the labor-intensive nature of traditional cultural practices. People need work. However, increasingly people migrate to cities. They will not be able to farm there - and it is doubtful if traditional farming practices would enable them to be fed there. Another objection is that traditional cultural practices produce less per hectare and thus put greater pressure on the wild environment. Land is increasingly scarce. The more land used for farming, the less rainforest, and the greater the pressure on biodiversity.

In contrast, what she says about BT ingestion is unconvincing. The evidence for the safety of BT is derived from experiments on animals other than humans. However, if I've got it right (if not, please correct me) we understand why BT is not toxic to animals: it is because their digestive systems are fundamentally different from those of insects. It is thus possible to predict with confidence that BT will also be safe to human beings, because they are much more closely related to animals than to insects.

Tim Roberts, UK
twr@compuserve.com

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 10:47 AM
To: 'biotech-room1@mailserv.fao.org'
Subject: Molecular markers - Examples from developing countries?

[Thanks to Dr. Srinivasan for a good contribution which raises the subject of the appropriateness of marker-based technologies in developing countries. Only 5 previous messages have referred to marker-technologies (Robert Lettington, 24/3 ; Mark Guiltinan 24/3 ; Danladi Dada Kuta 30/3 ; Edo Lin 30/3 and Werner Schenkel 4/4.......Moderator]

As suggested by the Forum Administrator, I wish to raise a query on the impact of molecular markers in development of genotypes useful for developing countries. It is an undeniable fact that molecular marker-based technology is effective for identifying and mapping quantitative trait loci (QTLs) in many crops. However, the impact of marker-based QTL analysis on the development of new genotypes with improved quantitative traits has been less than satisfactory, barring a few examples in tomato and maize. If my perceptions are wrong, I would appreciate if participants of this conference can identify a few examples of genotypes that have been developed using marker-based QTL analysis especially in crops of importance to developing countries. Tanksley and Nelson (1996) pointed out two reasons for such a low impact:

1. The discovery of QTLs and variety development are two separate processes.
2. Most breeding-related QTL studies have been targeted toward the genetic manipulation of quantitative traits in elite germplasm. Further, at least in some crops, there is a significant interaction of QTLs with environments. Are there other reasons and if so, can we do something about it?

A researcher from Ghana recently expressed interested in utilizing RFLP technology for differentiating the sex of nutmeg seedlings. Because Nutmeg is a dioecious species, farmers are unable to determine sex until flowering, which takes about 6-8 years. Likewise, a few other researchers are interested in employing this technology in tropical fruit crops. It would be good if someone on this conference can list out successful examples of employing marker-based technologies in resolving problems that have been difficult with conventional techniques.

Reference: Tanksley, S.D. and Nelson, J.C. 1996. Advanced backcross QTL analysis: a method for the simultaneous discovery and transfer of valuable QTLs from unadapted germplasm into elite breeding lines. Theoretical and Applied Genetics 92:191-203.

Ancha Srinivasan, Ph.D.
Senior Researcher, Regional Science Institute
4-13, Kita 24 Nishi 2, Kita-ku, Sapporo 001-0024 JAPAN
Tel: +81-11-717-6660 Fax: +81-11-757-3610
E-mail: ancha@vtt.co.jp or ancha_s@yahoo.com

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 1:48 PM
To: 'biotech-room1@mailserv.fao.org'
Subject: Re: Molecular markers - Examples from developing countries?

We are working on 2 sweetpotato projects together with Centro Internacional de la Papa (CIP), Lima, Peru using marker technology.

One is to characterise the world population using gene bank and regional samples. Already RAPDs could reveal improved insight in global dispersal routes, other marker types are now used to build a system for tracking germplasm bank duplicates and assessing provenance.

The second project is to set up molecular linkages with drought tolerance and other parameters. We consider this as necessary basic work to improve and enhance breeding. Transformation technology is another option. The two approaches are complementary rather than interchangeable.

Josef Schmidt
Head, Biotechnology Department
Austrian Research Center Seibersdorf
A-2444 Seibersdorf, Austria
phone: +43 2254 780 - 3519
fax: +43 2254 780 -3653
email: josef.schmidt@arcs.ac.at

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 1:50 PM
To: 'biotech-room1@mailserv.fao.org'
Subject: Re: Molecular markers - Examples from developing countries?

[Thanks to Edo Lin for comments and useful references below....Moderator]

I think that Dr. Srinivasan makes some excellent points. However, it also must be borne in mind that the science underlying QTL mapping is still relatively new and a lot of developments are underway. It may be useful to include some links here :

QTL Mapping Resource Page
http://www.informatics.jax.org/~cjb/qtldb/qtl_home.html
QTL in cereals
http://wheat.pw.usda.gov/ggpages/maps.html
Wild species genes in rice
http://www.news.cornell.edu/science/Aug97/WildRice.bpf.html

In addition to germplasm improvement, QTL and other mapping tools provide valuable contributions to taxonomists which is important in the context of the Biodiversity protocol and the sustainable conservation of Plant Genetic resources.

See, for example, the Experimental Taxonomy page at
http://www.ipk-gatersleben.de/

I am not a specialist on QTL and mapping but I have found references to the following crops : maize, rice, wheat, barley, oats, onions, sugarcane, tomatoes, beans (Phaseolus vigna), pawpaw and rye.

Also many references to tree species but that is a subject for the second conference.

Edo Lin,
France

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 4:53 PM
To: 'biotech-room1@mailserv.fao.org'
Subject: Re: pest res. to Bt / GM and human health

[Three responses (A, B, C) to Mr. Robert's message of 12 April....Moderator]

A)
Concerning paragraph 2: you are right, but the way you say it is not totally correct.
1) Insects are animals, and the Bt toxin has been tested for inocuity on mice, which are mammals, like us. Bt toxin is not toxic for mammals because their digestive systems are diferent than insect ones.

2) Digestive system of most mamals include a stomach with a low pH (pH=2 in human stomach) that denature most of the proteins, including Bt toxins. Denaturing does not mean destroy, but mean destroy specific activity related with structure. I would like to make a comparison with a pullover: if one completely un-ravels it, it is not destroyed (you always have the same amount of wool) but it has lost its capacity to protect you from cold that was correlated with the structure. Bt toxin activity does not exist anymore if it is denaturated.

3) Bt toxin's activity is to prevent chitin anabolism. Chitin is the major constituant of insect's exoskeleton that cover all the skin, including digestive system. Because chitin anabolism is prevented, the insect's digestive system loses it's stability and destroys itself. Humans and mamals do not anabolise (i.e. make) chitin. Because of this, the activity of Bt toxin cannot be harmful to them. That does not mean that Bt toxin "must" be safe, that mean that eventual nocivity (that finally does not exist) is not directly related to principal activity. Theorically, allergies could exist, or it is not a priori totally impossible that Bt toxin blocks another anabolic pathway. As a conclusion, as you said, Bt toxin has been tested and proved not to be toxic on mice. Numerous humans ate it, and finally no allergies was detected.

Romain Berruyer, France
Ph-D student, berruyer@cirad.fr

B)
1) Concerning labor-intensive agriculture and migration to cities.

There have been occassional postings throughout this conference expressing the need to support labor-intensive agriculture in those areas where migration is not an issue. Adequately feeding and supporting people on such a large scale in developing nations willl require regional solutions. Ms. Salzman's point is well taken in that respect.

2) Concerning "The more land used for farming, the less rainforest...":

It is necessary to introduce the consumption patterns of people in developing nations to address this concern. Any displacement of rainforests for agricultural land is strictly to support the cattle-exporting businesses to developed nations. The loss of rainforest is due chiefly to feed cattle, not people, and people in developing countries do not reap the benefits of this land-intensive agriculture.

Jeffrey Reel
jeffreyreel@aol.com
Planetary Food Council, a division of One Peaceful World
Becket, MA, USA

C)
Mr. Roberts is fundamentally correct that expanded farming means less forest habitat. But expansion of the land devoted to farming is necessary only if
1)population is growing and
2)farmers are forced to intensify production or grow cash crops for export for income or debt reduction, rather than for subsistence and local markets.

Lorna Salzman, USA
718-522-0253; 631-653-3387
lsalzman@aba.org

-----Original Message-----
From: Biotech-Mod1
Sent: Wednesday, April 12, 2000 5:24 PM
To: 'biotech-room1@mailserv.fao.org'
Subject: Re: Molecular markers - Examples from developing countries?

[An excellent contribution....Moderator]

Unfortunately I can only give a example of an attempt to use QTL analysis for stress improvement with limited success. The background is the problem of soil acidity and Aliminium-toxicity in red soils of Indonesia.

The problem is without doubt worth being dealt with, since an estimated 40% of world´s arable land is concerned. Marker assisted selection (MAS) seems to be a promising approach, since there are hints for the possibility of genetic improvements to overcome the problem. Since the trait is extremely complex, gains from conventional breeding are expected to be very slow and limited in overall success. Despite this promising basis, the results of the approach will be limited due to following reasons.

1. QTL analysis requires extensive field testing to reference markers, but the project was restricted mostly to biotech.
2. Development of markers is time-consuming but results are expected in 5 years only.
3. Marker assisted selection cannot replace conventional breeding but only adds a technology to a existing system. This is not sufficiently considered. Marker assisted selection can only be successful if it is preceeded, accompanied and followed by a excellent "conventional" breeding strategy.
4. There was no time and money allocated for validation of identified markers and implementation in a breeding system.

I am convinced, that utilisation of QTLs is at least one step ahead for most developing countries, since it is the most demanding marker technology. A reasonable precedure would be to:

1. Establish a sound conventional breeding system with medium and longterm goals and strategies !!!!!!!!!!!!!
2. Use markers to estimate, evaluate, and monitor genetic diversity to develop breeding strategies.
3. Identify important monogenic traits that are difficult to handle conventionally (e.g. sex in Nutmeg, virus resistance).
4. Develop markers for these monogenic trait. This might be best done in cooperation with developed countries or CGIAR centers.
5. Implement these markers in national breeding strategies.
if this works-
6. Identify a important quantitative trait and work on it by conventional breeding and extensive field trials until basic genotype x environment interactions are understood.
7. Streamline the breeding process by identifying QTL markers, and utilise them.

Of course some of these steps might overlap.

Experience shows that in Germany, small and medium breeding enterprises are only very slowly starting to use MAS due to high costs. Conventional strategies are in most cases still competitve. If MAS is used, markers are generally provided by public research. Therefore I am afraid that most developing countries will not be able to establish a systematic utilisation of the technique on a national level in medium-term.

The more important is it to enable centers of the international agricultural research to develop markers and maps, that can be used by national breeding systems. There is no question that marker techniques are appropriate, if "appropriate" is reduced to the meaning "beneficial". This view might change with the meaning of "cost-effectiveness".

Werner Schenkel
TU Muenchen-Weihenstephan
Institut fuer Pflanzenbau und Pflanzenzuechtung
Alte Akademie 12
D-85350 Freising
Tel.: xx49-8161-713749
Fax: xx49-8161-714511

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