FORESTRY AND GENETIC ENGINEERING

Genetic engineering is an occupation that deals with the addition of hereditary material taken from the same or another species or artificially produced to an organism, or the neutralization of some hereditary characteristics of the organism, and which has recently been mentioned frequently both in science and in the world of magazines.

The first important study in this area was carried out on a bacterium in 1973. A similar study was carried out in the mouse, which is a mammal, the following year. Insulin-producing bacteria was commercialized in 1982, and genetically modified foods have been sold in various countries around the world since 1994¹.

One of the applications of genetic engineering is the transfer of genetic material isolated and reproduced from an organism to another organism. This transfer can be done indirectly using the vector (*) or directly using micro-encapsulation and gene gun methods. If the transferred gene is taken from another living species - in general - it is called “transgene”, if it is taken from the same living species it is called “cisgene”. Depending on the state of the transferred gene, the newly formed organism is called “transgenic” or “cisgenic”². The application areas of genetic engineering techniques, whose main areas of use are agriculture, medicine and pharmacy, are becoming more diverse and widespread day by day.

The first genetic engineering application on forest trees was carried out in 1987³. In general, it is stated that the application of genetic engineering in gymnospermae trees (coniferous) is more difficult than in angiospermae trees¹⁶. It is stated that Agrobacterium tumafaciens (see. Vector)⁷ is used for gene transfer to poplar and eucalyptus trees, and gene gun method is used in Pinus radiata species⁸.

As the world population increases, different demands for forest areas and products are also increasing. Therefore, it is necessary to increase the production in order to meet the increasing demand from the ever-shrinking areas for wood production. In this context, the use of seedlings with high production capacity in addition to different plant nutrition, soil cultivation and silvicultural processes has made forestry one of the most important components of afforestation studies in advanced countries.

If trees that have been bred with traditional methods are also considered within the scope of GM (Genetically Modified), it would not be wrong to say that the history of GM trees goes back to the middle of the 18th century, when human beings started scientific forestry studies in the European Continent. The aim has not changed much since then: production of more and faster logs of the desired quality. At that time, individuals with the desired qualities were determined by traditional methods, and seeds were obtained from these individuals, and it was tried to transfer the desired qualities to future generations. Although tree breeding studies have gained many new scientific dimensions since the 18th century, they are still based on the same logic.

Genetic engineering applications, which are thought to be much faster than traditional breeding studies, are tried to be applied in the field of forestry in various countries and researches are carried out on this subject. These studies bring with them many debates as in GM foods. The life cycle of forest trees lasts for many years, and therefore, genetic engineering applications to be made in forest trees contain much greater unknowns and dangers for ecosystems than one or two-year herbaceous plants.

After the first GM poplars were planted in Belgium in 1988, hundreds of field trials were conducted. In 1993, Japanese car manufacturer Toyota conducted more carbon sequestering GMT (Genetically Modified Tree) trials and was able to increase the carbon sequestration capacity of trees, despite increased water consumption³. China started gene transfer studies for the black poplar (Populus nigra) in 1989, and made trial plantings in 1994. In 1998, black poplar was allowed to be planted in various administrative divisions of China¹⁵. In 2002, the China Forestry Administration approved the commercialization of GM poplar trees, and more than one million insect-resistant GM poplars have been planted in China³. In 2007, forestry researchers from Oregon State University were able to control the height of poplar trees using genes from Arabidopsis sp., a plant of the mustard family¹⁸.

The image below shows the level of studies of countries in the world on GMT as of 2004. The light green color indicates that the GMT studies in those countries are at the field trial level, and the dark green color indicates that the GMT has been commercialized in that country. Countries with laboratory-level studies are shown in orange, and countries where no studies have been made are shown in gray.

                Source:http://www.fao.org/docrep/008/ae574e/AE574E04.htm#P319_60465

Lignin, which is one of the three basic components of wood (the others are cellulose and hemicellulose), is a substance that provides structural support, strength and hardness to the plant, as well as providing resistance against pests such as fungi, insects and viruses due to its molecular structure that is difficult to decompose¹¹.

In order to reduce paper production costs by using less chemicals in pulp production, ways to produce GMTs containing less lignin are being studied. Reducing the lignin content in wood by 1% provides a 1-1,5% increase in pulp production and billions of dollars in savings to the global paper industry⁶. Wood-forming trees with 20% less lignin and higher cellulose content could be produced, but this created another problem. Trees with reduced lignin were less resistant to storms and virus attacks³. On the other hand, clone 7-56, a naturally occurring mutant of Pinus taeda found naturally in southeastern USA, is being produced on a large scale due to its better growth and better pulp yield with lower lignin content, and no adverse effects have been reported. This clone can be given as an example that the same phenotype can be achieved by both conventional methods and genetic engineering applications⁶.

The gene taken from a bacterium called Bacillus thuringiensis was transferred to forest trees, enabling the trees to produce their own insecticidal chemicals. The same GM poplar species was widely produced in China after the insects feeding on GM poplars died and there was short-term success. Although significant savings were achieved in the use of insecticides at the beginning, it is stated that after six to seven years, the boll worm that stays on this plant gains resistance to the insecticidal effect of GM trees³.

It is aimed to produce effective and easy weed control in nurseries and afforestation areas by producing GMTs that are resistant to herbicides. GMT production studies are also carried out with the aim of cleaning the chemical pollutants in the soil³.

The natural transfer of the transferred gene or genes in the GM organism, called transgene escape, to its wild congeners, may cause genetic pollution and the beginning of an unpreventable process.

It is stated that the probability of gene transfer (transgene escape) between living things decreases as the taxonomic distance increases⁶ but when trees are concerned, perhaps this issue should be approached a little more carefully.

Trees in general, and of course GMTs, can also exchange genes with their natural congeners at great distances. Producing forest trees that do not bloom and therefore do not produce pollen and seeds is suggested as a solution in order to prevent the genetic pollution that may arise from pollen and seed movement that is too long to be controlled (it has been determined that pollen can reach a distance of 600 km in a pine species). There is no solution to the deficiency in the ecosystem that will be created by a "monoculture" forest without flowers and seeds that will cover an area of ​​hectares. In addition, it is not known for certain whether the trees that can survive for hundreds of years and that are produced without flowers will bloom at some point in their lives, and it is very difficult to control. "It is stated that transgenes are generally in a stable structure", but it has also been shown that this stable structure can change with the effect of temperature, for example.

When we look at the issue of gene escape from a completely different point of view, we can see that the form and perception of the problem are very different. Genetic engineering studies and research and development (R&D) activities in this field have huge costs. At least for this reason, it is undoubted that a company producing GMT -possibly an international- will want to protect this product and patent it. After this product is marketed under market conditions, any farmer or forestry enterprise can buy the product and plant it on their land. In such a case, the specific gene in the GMT grown on your neighbor's land can be passed on to the seeds of the tree in your field and thus to the second generation of that tree. In this case, the "children" of your tree carry a patented gene, and you have these genes without paying for them. What legal consequences could such a situation have? Let's look at it from a slightly different angle; Or you perceive this involuntary gene exchange as a genetic contamination and you want to sue your neighbor…

The effects of GMTs, which are produced in large areas with increased competitiveness, as an invasive species can also be seen - perhaps even seen - . Considering that the distribution of forests made up of GMTs on the world is very limited today, when the pressure of exotic species on natural species is evaluated, the extent of the possible threat posed by GMTs can be estimated to some extent.

In the USA, it is stated that 42% of the species on the endangered or threatened species list are under the threat of alien species, and this puts a burden of 138 billion dollars on the US economy (in 1999 figures)⁹. Considering that foreign species may bring foreign parasitic species, and foreign parasitic species may bring other foreign predators or parasites, it seems very difficult to predict where the effects of new species entering the ecosystem will be.

In fact, genetic engineering applications in forestry aim at the qualities that today's foresters try to achieve through methods such as silviculture, combating forest pests, and breeding. Tall, smoother and fuller trunked, resistant to herbicides, viruses, bacteria, fungi, pests, growing faster, containing less lignin, more cellulose, more resistant to drought, frost, fire, requiring less nutrients, being more adaptive to different environmental conditions, resistant to chemical pollution, salt, …. This wish list can be extended more.

Whether the starting point is ecological or economic, producing GMTs is like sailing to an unknown ocean, it is very difficult to predict what will come our way in a few years. How does an insectivorous forest affect other insect-eating or agricultural activities in the environment? What impact there might be of the fact that not having a single weed on the ecosystem in a herbicide-resistant afforestation area? As for being able to do weed control easily, what effects can this have on soil and groundwater when the use of herbicides increases? Would it be the beginning of an unavoidable process when GMTs exchange genes with naturally grown forest trees? Or, what effects can a forest that produces no flowers or seeds have for organisms that feed on flowers and seeds?

The reflection of the issue on the international processes at the state level, IPCC (Intergovernmental Panel on Climate Change), UNFCCC (United Nations Framework Convention on Climate Change), CBD (United Nations Convention on Biological Diversity) is as follows.

It was stated that at the COP – 9 meeting held in December 2003 by the United Nations Framework Convention on Climate Change, afforestation projects with GM trees were recognized¹³.

The United Nations Convention on Biological Diversity, at the COP-8 meeting in Brazil on March 31, 2006, recommended that all countries approach this issue with caution, as GM trees carry many uncertainties in terms of global biodiversity and human societies¹⁴.

It is stated that GMTs are included in the Kyoto Protocol (IPCC, 2007) as vehicles that generate carbon credits (**) under the Clean Development Mechanism¹².

Although there is no regulation specific to forests and trees in the European Union legislation, the directive 2001/18/EC regulates market presentation and monitoring of GMOs, the 1946/2003 "regulation" regulates the movement of GMOs to third countries and their consequences, the exchange of information to prevent potential-threats¹⁷.

If the subject of GM forests is examined in terms of certification of forests, which is increasingly mentioned in the forest products market and is expected to increase in importance, the following question comes to mind: Should GM forests be certified or not?

Certification includes two key components:

1) Certification of forest management (management),

2) Certification of forest product.

Certification of forest management is based on the assessment of forest management against contemporary sustainability criteria. Product certification, on the other hand, ensures the assurance of the process from the certified source of the product (log, timber, etc.) to the delivery to the customer, in other words, the assurance that the product in question comes from a certified forest. Certification bodies are divided into two in terms of certification of GM forests (forest management); Those who are against the certification of GM forests and those who approach this issue moderately. Philosophical debates about nature and artificial continue on the level of perception of biotechnology between pros and opponents of GM⁶.

Basically, the question in terms of certification, which can be summarized as a marketing effort to support and disseminate sustainable forest management, is "Are GM forests sustainable or not?" This question brings us back to the discussion we had at the beginning.

(*) Vector: A piece of DNA used for gene transfer to an organism. 

(**) Carbon credit: A term/unit derived from buying and selling the right to emit one tonne of carbon dioxide or another greenhouse gas equivalent to one tonne of carbon dioxide.

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