Studies of biocontrol agents yields high results

Officials from the ministry of agriculture provided an overview for the implementation of the ASEAN national guideline to regulate the trade and use of biological control agents, a step forward for adopting green farming technologies that can increase yields and reduce the damage to crops, while also weaning the country off the dependence of chemical pesticides.

At the workshop hosted last month in Battambang by the ministry of agriculture, Cambodia HARVEST—a USAID funded programme — and the German international cooperation (GIZ) ASEAN Sustainable Agrifood Systems (ASEAN-SAS), participants from farmers to various private and public sector entities were introduced to a variety of biopesticides and biofertilizers, while numerous agricultural companies showed their support to the commercial production and distribution of biological control agents (BCA).

Claudius Bredehöeft, project coordinator of GIZ ASEAN-SAS in Cambodia, said that while less than one per cent (at least 3000 hectares) of farmland in Cambodia is certified as organic—free from the use of chemical pesticides, herbicides and contaminated runoff—there is a growing demand both, locally and internationally, for chemical free products.

“You see it in some local shops and in AEON Mall, Cambodia organic produce is growing,” he said.

However, export demand is where the benefits really lay. As The Post previously reported earlier this year, the Cambodian Center for Study and Development in Agriculture (CEDAC) shipped 540 tons of organic rice internationally in 2014, a 20 per cent increase compared to 2013. Its goal was to double the amount in 2014.

“Farmers can earn up to 30 per cent more for organic rice, as well as getting a free trade premium,” said Bredehöeft. “This also allows farmers to use their money for village development.”

Dr. Thomas Jaekel, a regional GIZ expert, used a case study from Chiang Rai province in northern Thailand to dispel the myth that BCA is cost prohibitive by laying out the economic benefits for cabbage production. Using Bacillus thuringienis, a soil dwelling bacteria, he showed how the cabbage damaging flea beetle can be managed without the use of chemicals. His study concluded that by using traditional pesticides in the dry season, production on a one-hectare farmland incurred a loss of $1161, while using BCA’s produced a profit of $427.70.

Keng Sophea, deputy director of the Department of Horticulture and Subsidiary Crops, provided results of using Trichoderma, a fungus that is found in all types of soil and is widely used for sustainable organic farming.When introduced to crops, Trichoderma acts as a fungicide that guards against insects and toxins and naturally boosts yields. According to his data, its use has raised production by 20 to 30 per cent.

“By applying to both root vegetables and rice, the fungus has a multi-function. It boosts the plant’s immunity, strengthens roots and also enriches the soil,” he said in a phone interview. He added that farmers using chemical pesticides and chemical fertilizers pose the risk of damaging their soil, thus making crops more susceptible to disease and insects.

“Compared to using chemicals, this is a big change in Cambodian agriculture. It not only ensures the health of the farmer by not having to use hazardous chemicals but also provides the consumer with a healthier products and is safe for the environment,” he said.

According to Sophea, 100 farmers in five provinces have been participating in a trial use of BCA over the last four years. The trial involved applying the fungus to rice, cucumbers and fruit trees, such as mango and durian. The data that he has gathered has been tremendously positive, with the fungi killing the vast majority of pests and bacteria that once attacked the roots of the plants. For cucumbers, although the mechanism of action has yet been discovered, he has found that the fungi acts like hormone-boosting enzyme that both strengthens and produces larger vegetables.

However, although optimistic about his results, Sophea acknowledged that the adoption of BCA use for individual farmers might be difficult, because the level of training and education for handling a living organism is hard to grasp for those who are used to chemicals as the first and last line of defense.

Nevertheless, Sophea hopes that BCA use will soon become abundant because it “will allow us to grow safe and organic produce that can be consumed locally and exported abroad,” he said, adding that Trichoderma is enormously inexpensive compared to chemical pesticides. A kilogram of Trichoderma costs $8 a kilogram and can treat up to 1000 litres of water.