Filipino farmers reap economic benefits from GMO corn, study finds

By Joan Conrow

July 2, 2021

Filipino farmers, including low-income households, have benefitted economically from growing genetically modified (GM) corn, according to a new study.

The study, published in the International Journal of the Science of Food and Agriculture, was conducted to assesses the economic value of growing GM corn in the Philippines between 2002 and 2019. Cultivation of GM corn has expanded rapidly in that time, with the amount of acreage increasing by an average of 31.24 percent each year. Currently, some 460,000 farm families, or a third of all corn farmers in the Philippines, are now planting GM corn on about 835,000 hectares.

Farmers achieved higher income due to the increased yield of GM corn and reduced use of pesticides. Though the national average yield for non-GM corn is typically just 3 metric tons per hectare, GM corn can double or triple this output. As a result of improved yields and better-quality harvests, the Philippines has been able to export corn silage since adopting GM corn.

Productivity growth of the country’s corn industry was estimated to be 11.45 percent higher due to GM corn adoption, according to the study. The total welfare gain, as measured by the equivalent variation of income, reached $189.4 million, or nearly a tenth of a percent of total household income.

“Not only was the gain positive for all household income deciles, it was also inclusive: lower household income deciles benefit from the GM technology more than richer households,” the authors wrote. “The middle class benefit the most.”


Corn is the third most important crop in the Philippines in terms of area harvested and economic value. Furthermore, some 600,000 Filipino farm households depend on corn as a major source of livelihood, the authors wrote. The country produced 4.5 million tons in 2000 and 8 million tons in 2019, with the area of harvested corn declining even as production increased, reflecting the improved yields of GM corn.

The Philippines approved GM corn for commercial use in December 2002, primarily to help farmers control the Asian corn borer, a highly destructive insect pest that lowers yields and can destroy up to 80 percent of a crop. Farmers were using pesticides to fight the insect, which created a human and environmental health risk and increased production costs for farmers. The pest is estimated to account for up to 80 percent profit loss for corn farmers.

The GM yellow corn includes a Bt (Bacillus thuringiensis) gene that gives the crop natural resistance to the pest. Other varieties have since been introduced that offer herbicide tolerance traits, meaning farmers can spray to control weeds in their fields without destroying the corn crop, as well as both pest-resistance and herbicide-tolerance traits. Since October 2020, a 42 GM events have been approved for use in the Philippines, with 30 for direct use as food, feed or processing and 12 for commercial planting.

The researchers estimated total factor productivity (TFP) growth of corn production with and without GM technology and then assessed the economic implications of using the technology through a computable general equilibrium (CGE) model of the Philippine economy.

“The adoption of GM technology in corn production in the Philippines is positive and significant,” the authors wrote.

Image: Corn field in the Philippines. Shutterstock/Vimada Lew