EDITOR’S note:

Prof Xu Zhihong is a plant biologist and former president of Peking University. He is also a former vice-president and member of the Chinese Academy of Sciences. Shanghai Daily reporter Li Xinran held an interview with him to discuss public concerns regarding genetically modified crops.

Q: What are global trends with genetically modified (GM) crops?

A: Genetically modified crops have been extensively planted for almost 20 years. Starting from the US in 1996, the acreage of genetically engineered crops has increased 100 times worldwide and reached 170 million hectares by 2012, or 1.4 times China’s total farmland.

They are rapidly adopted despite different views over the issue. The application of GM crops used to be mainly in North America but more and more developing countries have joined the club, like India, Brazil and Argentina. China used to take second place but has already been surpassed by many other countries.

Among the most commonly planted crops, more than 81 percent of all soybeans, 64 percent of cotton, 29 percent of corn and 23 percent of canola (oil rape) globally are from GM seeds, according to the International Service for the Acquisition of Agri-biotech Applications.

Business applications have started in many of the 29 countries and regions worldwide that now plant GM crops. About 95 percent of the soybean and 75 percent of the corn plantations in the US are genetically modified. They have acquired governmental approvals and been proved harmless by research.

Europe behaves more conservatively over the issue but GM crops are still adopted in some of its countries. The European Union grants imports of officially approved GM products from countries like the US. So GM farming has been on an upward trend globally.

Q: People ask: “Are GM crops safe to human beings?” What’s your opinion?

A: It is meaningless to discuss whether genetically modified plants are safe or not. We shall do our analysis case by case. Genetic engineering technology itself is neutral. It depends on what gene you introduced or modified. Cross-breeding usually is the same. Whether a GM crop is safe depends on what role a specific transferred gene plays.

For example, the insect-resistant Bt protein was translated and widely known as a toxic protein in China but there are many different Bt subspecies. They have specificity to kill different types of insects. The Bt protein killing cotton worm has nothing to do with other insects like mosquitoes or flies, not to mention other animals or even human beings.

The protein has been introduced to genetically modified soybeans and corn. Since many people suspected its toxicity, scientists have done a lot of research and tests. According to test result published by US Environmental Protection Agency, a normal-sized human who swallows 200 grams of pure mon 810 Bt protein once is still safe. There is also no evidence suggested it could do harm to our reproductive system. But many of us have no idea about the test and its result. Data from many other similar tests can prove that licensed GM crops are safe but few people knew their whereabouts or understood their meanings.

Q: How do you think of the arguments in favor of or against GM crops?

A: Genetic engineering is controversial not only in China but also worldwide. The Institute of Plant Physiology and Ecology as well as the Chinese Society of Plant Biology hold events on Plant Day every year to introduce plant science to the public, including genetic engineering technologies. It works.

But China is a large country with countless people. It is reasonable to have different views on the same issue. But the point is we shall argue or discuss on a scientific and rational basis rather than turn it politically.

Some media reports demonized the technology. That’s why a lot of domestic scientists are unwilling to join the debate. If someone supports GM crops, he or she will be tagged as a collaborator while some even claimed that transgenic technology would ruin our state and destroy our race. It is improper and similar to what happened in the “cultural revolution” (1966-76). To support or oppose is due to different reasons. Europe behaves very conservatively on genetic engineering but the debate there is based on scientific data and evidence.

In many cases, genetic engineering can solve specific problems. Papaya ringspot virus dooms papaya, and viral pesticides have nothing to do with it. The papaya industry in Hawaii and globally could be destroyed as the production dropped more than 90 percent in a decade because of damage caused by the virus.

If genetically modified papayas with virus resistance had not been developed we would have no papaya to eat today.

GM crops are not only insect-resistant or herbicide-tolerant but can play more important roles in the future as scientists are doing research to introduce drought-tolerant or salt-tolerant genes to crops like wheat and poplar tree.

Q: Are GM crops a threat to the natural environment?

A: One of the significant environmental benefits of GM crops is the dramatic reduction in pesticide use. Pesticide use in the US was reduced in the past 10 years thanks to the extensive plantation of GM crops. China is the same. Cotton in China used to be the most heavily sprayed crop, but after the application of genetically modified cotton pesticide use has dropped 80 percent.

China consumes more than one third of the total output of pesticide and chemical fertilizer worldwide every year. China’s acreage of farmland is lower than the US, but China uses more pesticide and chemical fertilizer than the US does. Pollution caused by agriculture has accounted for half of the total in China.

For the sake of that, reduction in pesticide use is an effective way to improve the environment.

Scientists are doing research to work out nitrogen-efficient crops that needs less fertilizer so that the fertilizer use will also be cut in the future.

Actually people are worrying more about future climate change and extreme weather conditions. If the world’s average temperature rises just 1 degree Celsius, major crops will have their output dropped by at least 10 percent. Though some crops would gradually adapt to the future weather, it would be too slow for human beings. Genetic engineering may help us develop crops to better adapt to extreme weather conditions or allow some wild species with potential to better serve our future life.

Q: Is there a clear road map that will lead to the commercial application of GM food grains in China?

A: Generally speaking, the development of GM crops in China is stepping forward but also affected by some factors. Anyway, GM cotton has made great success in China.

In the late 1980s China had its cotton output cut in half because of damage caused by the cotton bollworm. Even pesticides were useless.

At that time, American scientists had developed Bt cotton to ward off insect pests. Monsanto Company attempted to sell its technique to China at a quite high price but Chinese scientists had launched their own research and China later had its own Bt cotton.

Now more than 80 percent of cotton planted in China is based on China’s own biotechnology. If we don’t have our own biotechnology we’ll be under the control of foreign companies like what happens in India today. India adopts American technology for its cotton plantations but doesn’t have its own patents. That’s why it relies heavily on American companies.

Genetic engineering has always been a controversial topic and scientifically needs further discussion over issues like food safety or environmental security. That’s why the application of GM crops is strictly approved in most countries.

The practice in China is even stricter than what carries out in the US.

If a company receives a safety certificate for its GM crops in the US it is approved to produce. But in China, after receiving a safety certificate a company has to acquire other paperwork like variety certification, crop seed management license and business license to launch its production. Industry insiders used to estimate the whole process needs three to five years.

When it comes to GM food grains, however, there is no clear road map. No one knows how to get the business license for GM food grains in China after receiving a safety certificate. There is no clear rule.

Two varieties of Bt rice and one transgenic corn strain with phytase gene have had their safety certificates expire.But no one knows what the next step is toward the business application.

Some domestic seed companies have invested heavily in R&D, but the situation right now may dampen their enthusiasm. If there is no clear road map, companies won’t go further. They have no faith to increase their input, but they play key roles in research and development as well as the application of GM crops.

In my opinion, the rules can be very strict but it should also be clear. It has become a problem for the application of certain GM crops in China now.