Journal Links

Journal Issues

USDA-Sponsored Workshop on Food Biotech and IPR News

Please click  marked highlighted here to go to the old news on USDA- sponsored multinational workshop on Biotech Food and IPA:HERE

The readers may be interested to read the following news items centering round the participation of a 2-member Bangladesh team to the recently held USDA workshop on Biotech Food and Intellectual Property Rights in Washington DC from August 20 through August 31-. The Bangladesh team was represented by Dr. Zeba I. Seraj, Dept of Biochemistry, Dhaka University and Mr. Reaz Ahmad, staff reporter, The Daily Star.

USDA- Sponsored Workshop at the last leg of their program. Visits  UCD

Salt tolerant tomato (top); Control (bottom)

Austin August 31, '01. The participants to the USDA-workshop spent their last working day at the University of California at Davis. They were taken to meet Professor Eduardo Blumwald at the Department of Pomology who, in collaboration with Dr. Zhang Hong-Xia of Botany Department at the University of Toronto bioengineered a salt tolerant tomato line by inserting  and  overexpressing a vacuolar Na⁺/H⁺ antiport gene that was shown to improve salt tolerance in Arabidopsis. In the picture at the top the fruit size of the salt tolerant line is shown to be slightly smaller compared to the two fruits of the control. The genetically modified transgenic tomato plants  were able to grow, flower and produce fruits in the presence of 200 mM NaCl. While the transgenic leaves accumulated Na⁺ to almost 1% of their dry weight, the fruits displayed only a marginal increase in Na⁺ content and a 25% increase in K⁺ content. The results of their experiments show clearly that   transgenic tomato plants can utilize salty water for growth.

Professor Blumwald explained that the strategy followed so long by breeders was to exclude sodium but in their approach they are allowing   Na⁺ into the cell, compartmentalizing it in the vacuole.

Since the Na⁺ was sequestered inside the vacuole, it did not have any toxicity on the other cell components. Since arabidopsis plants are not as sensitive to salinity as their tomato counterparts, overexpression of an Arabidopsis vacuolar Na/H antiport gene in tomato genome worked very well to exclude the transport of Na salts into tomato fruits. This strategy may prove helpful to breed salt tolerant lines of other crops.

Participants to USDA- Sponsored Workshop Spend Busy days at Pioneer Hi-Bred & a private  farm in Iowa

Logo of Pioneer Hi-Bred Intl.

Organizers of the USDA-sponsored workshop made arrangements for the participations to visit important institutions where work on biotech crops is going on in full scale.  At the conclusion of the workshop, the participants left for Iowa state. At Des Moines, Iowa, they visited the world famous Pioneer Hi-bred International establishments. In addition to maize breeding, visitors were shown bio-engineered soybean varieties,  some rich in oleic acid content, some in high sucrose content, nutritionally rich GM corn varieties and corn varieties resistant to root worm and corn borer. Their future program includes bioengineering  crop varieties capable of yielding biodegradable plastics, sequencing maize genome of varieties  to be used to produce hybrid maize. Aided by suitable computer model, the latter program is aimed at predicting the best cross combinations for  maximum yield combined with best agronomic characters. This will save the breeders to undertake myriad of crosses physically.

In order for the breeders to view the expression of useful recessive characters, at Pioneer Hi-bred stations, the breeders are growing somatic haploids. Individuals with promising characters are selected and incorporated into the breeding program. Another great advantage of haploidy is the shortening of breeding time almost into half; true breeding lines are obtained at one step through duplication of the chromosome numbers of selected haploid individuals.

On Tuesday, the participants went to Ames, Iowa, and visited a huge 3600-acre farm,  run by only  a handful of people. The owner showed the visitors large machinery that they use to prepare soil, plant seeds, and harvest large quantities of food grains. Each equipment costs around $100,000 which are available on loan from banks or heavy duty machinery companies lease them out.

On Wednesday, the 29^th of August, the workshop participants visited the Department of Agronomy at  Iowa State University.  Visitors were shown their microarray facilities which allow molecular biologists to study the composite gene function of a complex trait such as flowering, fruit ripening, vascular development etc., or their function in response to an environmental stress such as drought, gravity pull, heat or cold shock. Those genes that are activated or inactivated in the genome of the organism as a result of a stress can be identified in a microarray experiment.  cDNA fragments of the material of interest  are arranged in the form of  tiny square grids in a glass slide by a computer-aided robot.

Visitors were informed that microarray machines  cost  about a quarter of a million  dollars each*.  Equipped with computer aided automation (robot), these machines use  high throughput methods for not only depositing 20,000 different cDNA samples on a glass slide but also  isolating plasmid DNA from 500 recombinant clones in one day and send them for sequencing. (It costs about $3 per base pair.)  DNA samples are deposited by steel needles on a glass slide.  Needles which cost $ 200 each,  have  a built-in a very thin slit.  They collect DNA samples by capillary action and deposit   them simultaneously on poly-l-lysine coated slides  The needles then change alignment by about 0.5 mm and deposit another set of samples, next to the earlier slots of  eight. The process goes on until all 20,000 cDNA samples are printed on one slide.

The slide can then be hybridized with different cDNA's, labelled with different fluorescent probes. Once the machine is set up, the microarray work can be carried out routinely by trained technicians.  Since the expression of a complex character is the result of the interaction of a large number of genes which light up in the microarray, analysis and interpretation of data is the most difficult part of a microarray experiment. The University has 50 Ph.D. students specializing in  bioinformatics to do the above difficult task.

Previous