Biotech crops reduce pesticide use

By planting more biotech crops, the world will be a better place to live, according to the newly-published report of the International Service for the Acquisition of Agri-biotech Applications (ISAAA).

Aside from improved crop productivity and profitability, the report – entitled Global Status of Commercialized Biotech/GM Crops: 2016 – also examines other benefits of biotechnology.

The adoption of biotech crops has decreased the environment impact with a 19% reduction in herbicide and insecticide use, said Prof. Paul S. Teng, chair of the ISAA board, who launched the report in the Philippines.

From 1996 (the first year of biotech commercialization) to 2015, the world saved 620 million kilograms of active ingredients of pesticides. In 2015 alone, some 37.4 million kilograms was left unused.

The reduction was made possible through the use of biopesticides. For years, many organic farmers have used a bacterial pesticide called Bt to control a variety of pests that attack agricultural crops.

Bt stands for Bacillus thuringiensis, a common soil bacterium so called because it was first isolated in the Thuringia region of Germany. It produces a protein that paralyzes the larvae of some harmful insects.

Scientists, through genetic engineering, have taken the Bt gene responsible for the production of the insecticidal protein from the bacterium and incorporated it into the genome of plants. As such, the plants have a built-in mechanism of protection against targeted pests.

Aside from corn, Bt is also introduced in cotton, poplar, potato, rice, soybean, tomato, and more recently eggplant. “The protein produced by the plants does not get washed away, nor is it destroyed by sunlight,” said a briefing paper published by the Global Knowledge Center on Crop Biotechnology. “The plants are protected from the insects round the clock regardless of the situation.”

Since Bt crops are able to defend themselves against pests, the use of chemical insecticides is significantly reduced. A study conducted by the United States Department of Agriculture showed that 8.2 million pounds of pesticide active ingredients were eliminated by the farmers who planted Bt crops in 1998.

“Aside from being effective against insect pests, Bt crops have lower incidences of opportunistic microbial pathogens, such as the fungus Fusarium,” the briefing paper said. “This fungus produces mycotoxins that can be deadly to livestock and also cause cancer in humans.”

The briefing paper shares this information on how Bt operates: “When ingested by larva of the target insect, the Bt protein is activated in the gut’s alkaline condition and punctures the mid-gut leaving the insect unable to eat. The insect dies within a few days.”

It is for this reason why much research has been done to exploit the organism’s agronomic value. To date, there are more than 200 types of Bt proteins identified with varying degrees of toxicity to some insects.

In the past, Bt was cultured by fermentation. In fact, over the last 40 years, Bt has been used as an insecticide by farmers around the world. It is said that organic farming has benefited from it as it is one of the very few insecticides permitted by organic standards. “The insecticide is applied either as a spray, or as ground applications. It comes in both granules and liquefied form,” the briefing paper said.

The Rome-based Food and Agriculture Organization (FAO) of the United Nations estimates that up to 35% of the losses in the annual crop production worldwide are due to pests – insects, weeds, plant diseases, rodents and birds. Of the estimated one million insects in the world, between 150 to 200 species frequently cause serious damage to crops.

When losses due to pests are combined with postharvest losses, worldwide food losses would amount to 45%. “This is almost one half of the world’s potential food supply,” the FAO pointed out.

This is the reason why most farmers around the world use pesticide to control these pests. For a long time, no one seemed to question the safety of pesticides. Not until 1962, when marine biologist and writer Rachel Carson wrote the now classic Silent Spring. In her book, she described how pesticides cause long-term hazards to birds, fish, other wildlife, and humans, but provides only short-term gains to controlling the pests.

Despite her findings, pesticide use continues to soar. “Farmers now apply abut one pound of pesticides per year for every person on the planet, 75% of it in industrial countries,” Peter Weber, a researcher with the Washington-based Worldwatch Institute reported some years back.

In the Philippines, most farmers are using chemicals to control pests that attack rice. “Pesticides are like bombs being dropped in the food web creating enormous destruction,” said entomologist Dr. K.L. Heong, who once worked with the International Rice Research Institute.

Pesticides are killing more than just the pests. “Some pesticides harm the living organisms other than the targeted pest,” observed the Davao-based Technical Assistance Center for the Development of Rural and Urban Poor. “Some travel to the food chain to bioaccumulate in higher organisms.”

Gretta Goldenman and Sarojini Rengam, authors of Pesticides and You, explained that pesticides concentrated even to toxic levels via the food chain. Thus, an increase feeding on plant sprayed with pesticides might be eaten by another insect which might be eaten by a bird.

“Traces of pesticides too small to kill the targeted pest can accumulate to the levels high enough to harm species further on up the food chain,” the two authors warned.

Health experts claim pesticides can enter the human body through the lungs, digestive system, or skin. Depending on the pesticide, health effects can be immediate (acute) or they can occur after years of lower-level exposure.

Long-term effects of pesticides include skin disorders, damage to internal organs (liver, kidneys, lungs), increased sensitivity to pesticides and effects on the progeny.

All these harmful effects can be minimized if more farmers will adopt agricultural biotechnology. It uses a range of tools, including traditional breeding techniques, that alter living organisms, or parts of organisms, to make or modify products; improve plants or animals; or develop microorganisms for specific agricultural uses. Modern biotechnology today includes the tools of genetic engineering.

“Biotechnology provides farmers with tools that can make production cheaper and more manageable,” the United States Department of Agriculture (USDA) said in its website.

For example, some biotechnology crops can be engineered to tolerate specific herbicides, which make weed control simpler and more efficient. Other crops have been engineered to be resistant to specific plant diseases and insect pests, which can make pest control more reliable and effective, and/or can decrease the use of synthetic pesticides.

Meanwhile, pesticides continue to lose their effectiveness against crop-destroying pests as a result of genetic selection, according to the Worldwatch Institute.

At least 520 insects and mites, 150 plant diseases, and 113 weeds have developed resistance to one or more pesticides meant to control them. In addition, at least 17 insect species are resistant to all major classic of insecticides, and several plant diseases are immune to most fungicides used against them.

“Resistance to pesticides is as natural as evolution,” Weber reminded. “In fact, it is natural selection in fast forward, provoked by the very chemicals meant to control the pest. Resistant strains develop particularly quickly when farmers overuse pesticides and try to eliminate pests rather than control them. Kill 99.9 percent of the insects in a field, and the survivors are a superstrain.”

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