Saturday, August 08, 2015

Throwback: Plant Growth Regulators and Biotechnology

The article below is probably a little outdated, but the information are still relevant. :D

I remembered when I went to Consumer At Penang (CAP) office for job interview one year before I pursue my Master degree. 

The interviewer asked me about Genetic Modified Organisms (GMOs), and as a biotechnology student I told her about my past Cavendish banana tissue culture supervisor experience, dealing with plant growth regulators/ plant hormones to obtain adventitious shoots from banana sucker.

She suddenly interrupted me " Plant hormones is also  GMOs! Anything that is not grow naturally is GMOs!". 

Her strong opinion staggered me, before she quickly jump to the next question.

As a Biotechnology degree holder, those moment really kept me thinking sometimes. After 9 years, I finally heard one question that are very relevant, "How well does scientist communicate in sciences to public?" You know, with all the jargon and stuff?

As for another question that rises few years ago, yes, the anti-GMOs and anti-vaccines are the same group of people. 

We are curious whether these people are really anti-GMOs/ vaccines, or actually anti-technology/ progression.

Happy reading :D

Plant Growth Regulators and Biotechnology

Peggy G. Lemaux
Western Plant Growth Regulator Society presentation
Anaheim, CA
January 13, 1999
Full articles--> source


A plant growth regulator is an organic compound, either natural or synthetic, that modifies or controls one or more specific physiological processes within a plant. If the compound is produced within the plant it is called a plant hormone. A plant regulator is defined by the Environmental Protection Agency as "any substance or mixture of substances intended, through physiological action, to accelerate or retard the rate of growth or maturation, or otherwise alter the behavior of plants or their produce. Additionally, plant regulators are characterized by their low rates of application; high application rates of the same compounds often are considered herbicidal". Upon reading these descriptions, it strikes me that the definition is likely to be broadened, particularly as it relates to the EPA, as we consider changes that can be made through the modern methods of genetic engineering.
Exactly how do changes made through genetic engineering compare to classical methods of genetic manipulation? 

An example that contrasts the two approaches is helpful in understanding the differences and similarities between these two methods. Both classical and molecular approaches were used to increase the sugar content of the commercially available tomato. This work was made possible because certain wild tomato relatives, although unlike commercial varieties in appearance, have a higher sugar content. The plan was to transfer the higher sugar content of the wild tomato to the domesticated tomato and leave behind its smaller size, lower yield and bitter taste.

The classical breeding approach accomplished this goal through the mixing of genetic information from the two parents upon sexual exchange. After many cycles of backcrossing to the parental commercial variety, most information from the wild parent was eliminated but still some remained. In that uncharacterized bit of genetic material was the information for the sweetness characteristic, but also the information for an unexpected characteristic. The newly developed variety had lowered fertility. This is because the breeder did not have total control over exactly what information was retained in the new tomatoes. They tried to minimize the unwanted information from the wild species, but despite this effort they were unable to eliminate everything but the sweetness characteristic. They ended up with a new variety that still had a substantial input from the wild species and in that information was the sweetness characteristic and something that caused lower fertility.

In the genetic engineering approach, the researchers found a single piece of genetic information that when removed would slow the breakdown of sugar. Through genetic engineering technologies, they were able to build that characteristic into the commercial variety and stop sugar degradation in the commercial tomato. They did this by making a very specific change in a single gene. They changed nothing else about the tomato. Additionally, in contrast to classical breeding, they knew precisely what information they were adding. Another difference with this approach is that, although in this case the changed information came from the tomato species itself, it would have been possible to take that new genetic information from another plant species, a microbe or any other organism for that matter. In addition with this approach it is possible to "define" precisely when and where this newly acquired information will be made by using characterized regulatory regions that function when and where they are need


How is Biotechnology impacting agriculture?

What is being done with the new technology of biotechnology in the arena of plants. Today, there are products in the field and the marketplace. The new technologies of genetic engineering can result in more environmentally friendly plant pest-protection, foods with enhanced nutrition, more accurate and sensitive diagnostics, foods with improved processing and marketing characteristics, better and more efficient medical delivery, new methods for removing contaminants from soils and waters, and creation of products that are presently being made from nonrenewable resources. Many of these changes might be considered under the broad definition of a "plant growth regulator".

While products of this technology once were confined to the research laboratory, this is no longer the case. These and other new crops represent a substantial percentage of actual production acreage in the U.S. In 1998 50% of the cotton acreage, 30% of the soybean and 20% of the maize acreage in the U.S. were genetically engineered. In the U.S. some 60 million acres of G.E. crops were planted in 1998 and the projections for 1999 are that this number will increase, with a wider variety of products available to farmers and present in the marketplace..

In the short term and long term, what might some of these products be?



In summary, there are a number of areas relating to plant growth regulators that can be approached through genetic engineering that will likely impact agriculture in the coming decades. These range from engineered herbicide tolerance to male sterility, from improved pest resistance to terminator technologies and delayed senescence. While these technologies will certainly change agricultural practices, they will not be "magic bullets" that will eliminate the need for classical methods of plant production and protection. These technologies should be viewed as adjuncts to existing technologies that provide new tools for the farmer's and producer's tool box.