Farmers are crying foul over tariff-free imports of wheat and the resulting decline in maize and tapioca prices.
According to a Commerce Ministry source, a group has filed complaints that nearly 1 million maize and tapioca growers and their families are feeling the pinch from the wheat liberalisation policy.
They are also concerned about the rising amount of wheat being imported, the source said.
In 2014, Thailand imported only 593,000 tonnes of wheat. The figure rose to 3.46 million tonnes in 2015 and will reach an estimated 5 million tonnes this year.
Higher imports have affected domestic prices of maize and tapioca chip in recent years.
Maize prices are now quoted at 8.50-9 baht per kilogramme compared with 9.39 baht in the 2014-15 season. Tapioca chip prices now fetch about 6.40 baht per kg, down from 7.49 baht in the 2014-15 season.
Thailand has about 450,000 families of maize growers and 520,000 families of tapioca farmers.
Thailand waived import tariffs on wheat in 2013 at the request of animal feed producers. Ahead of 2013, wheat prices were about 1-2 baht higher than maize prices. With higher imports, wheat prices have been 1-2 baht lower than maize prices since 2014.
According to the source, the imports of corn DDGS (distiller's dried grains with solubles) were also found to have risen over the past three years. They increased to 462,000 tonnes in 2015 and 226,000 tonnes in 2014.
The imports had resulted in lower purchases of domestic maize, affecting farmers' income, the source said.
According to the Commerce Ministry, leading wheat importers include Bangkok Produce Merchandising Plc of Charoen Pokphand Group, Betagro Group, Laemthong Corporation Group, Sunfeed and United Flour Mill Plc.
The first four firms have imported wheat mainly to make animal feed, with United Flour Mill importing for human's food production.
The source warned that local maize and tapioca prices would definitely be lowered if wheat imports were freely allowed without any buffer measures, with animal feed producers no longer wanting to buy local produces.
Although the government early the year put wheat flour among the 41 items on the price control list, it has done little to dampen imports.
The price control list covers essential items for daily use such as food, consumer products, farm-related products (fertilisers, pesticides, animal feed, tractors, rice harvesters), construction materials, paper, petroleum and medicines.
Listed foods include garlic, paddy, milled rice, corn, eggs, cassava, wheat flour, yoghurt, powdered/fresh milk, sugar, vegetable/animal oils and pork.
Consumer products include detergents, sanitary napkins and toilet paper.
Businesses making or selling products on the list are required to inform the authorities of their production costs and seek approval before any price increase.