The rice weevil slayer: "Dr. Rice Weevil" Yao Meiji has stuck with his research for 31 years, protecting granaries across Taiwan

People use "rice weevil" to describe someone who is lazy and loves to eat, never knowing that Taiwan has a rare and tireless "Dr. Rice Weevil." Yao Meiji, an associate researcher at the Agricultural Research Institute, has studied rice weevils for 31 years, traveling all year round to farmers' association granaries across Taiwan, all to reduce the impact of rice weevils on paddy rice, helping every granary protect every single grain so people can freely enjoy bowl after bowl of rice. This one-of-a-kind rice weevil researcher in all of Taiwan recently won the annual "Outstanding Agricultural Education and Extension Personnel" award!

Carrying on rice weevil research from the Japanese colonial period, running strong for 31 years without pause

Yao Meiji, whose name sounds at first like a woman's, is actually a gentle and humble man; born in the 51st year of the Republic of China calendar, he is a devout Christian who completed his bachelor's, master's, and doctoral degrees in the Department of Entomology at National Chung Hsing University, and after finishing his military service he came to the Agricultural Research Institute, where he has worked for over thirty years.

"I used to study vegetable pests at school, and when I came to the Agricultural Research Institute I switched to studying rice weevils." Yao Meiji's master's research was on the pesticide resistance of the diamondback moth. Because of his entomology expertise, as soon as he joined the Agricultural Research Institute he was given the major task of carrying on "rice weevil" research. "At that time the rice weevil researcher was Mr. Lin Cong, who was 64 years old. He had been studying rice weevils since the Japanese colonial period, but when I came to the Agricultural Research Institute, he was just one year away from retirement."

In his first year, Yao Meiji learned from his mentor Lin Cong, and after his mentor retired, his mentor left an assistant to help Yao Meiji. In the days that followed, the retired Lin Cong would also come back from time to time to answer his questions, until Yao Meiji was able to stand on his own.

"The place I visit most often is the granary, and the task is to protect every single grain of rice as much as possible." Yao Meiji speaks in a gentle and even voice, but the moment he starts talking about rice weevils, he quietly speeds up.

Only pests that paddy rice encounters after leaving the field count as "rice weevils"

Eastern people rely on rice as their staple food, and whether measured by area or by yield, paddy rice is the country's number one crop. The Agriculture and Food Agency, which handles domestic crop production and marketing, even has a deputy director-general dedicated to rice. The pest of such an important crop, the rice weevil, is naturally public enemy number one.

When it comes to rice weevils, Yao Meiji first clarifies: "Only insects that paddy rice encounters after leaving the field count as rice weevils." He says the main pests in paddy fields, such as the striped stem borer, brown planthopper, rice leaf roller, and green leafhopper, have different feeding habits and lifestyles from rice weevils and are only suited to life in the field. "Most paddy rice pests are hemipterans. The brown planthopper, for example, likes to pierce and suck the sap of paddy rice, but once the paddy rice is dried into grain, the outer husk is very hard, and the brown planthopper's mouthparts simply can't pierce it."

But if the pests in the field and in the granary are different, where exactly do rice weevils come from? "If a granary isn't managed properly, you're basically raising the rice weevils yourself." Yao Meiji says that after harvest, paddy rice must go into a grain dryer, and the dryer is only used each year after the first and second rice harvests; the rest of the time it sits idle. If the grain dryer and granary are not cleaned regularly, the leftover grain on the dryer's conveyor belts and on the granary floor will attract rice weevils to "move in," and when the new grain is later dried or brought into the warehouse, it conveniently "restocks" the rice weevils.

The four common rice weevils in Taiwan: the rice weevil, the lesser grain borer, the angoumois grain moth, and the Indian meal moth

The rice weevil most people picture is the little black insect that surfaces when washing rice, that is, the rice weevil. But the rice weevil is only one member of the rice weevil kingdom. There are about five hundred species of rice weevils worldwide, of which about one hundred or more are found in Taiwan, and about 20 species are commonly seen today. Besides the most common rice weevil, there are also the lesser grain borer, the angoumois grain moth, and the Indian meal moth. The species span the Coleoptera and Lepidoptera orders, and the crops they damage are not limited to paddy rice; even the five grains and miscellaneous cereals can be targets of rice weevils.

Yao Meiji explains that different species of rice weevils damage at different times and locations, and they can be divided into primary damage and secondary damage. Rice weevils that can feed directly and cause damage belong to primary damage, while rice weevils that only come to feed after primary damage has occurred belong to secondary damage. The rice weevils encountered before and after the paddy rice husk is removed are also different: paddy rice stored in the granary with the husk not yet removed is easily damaged by the lesser grain borer and the angoumois grain moth; during the milling process it is easily damaged by the Indian meal moth; and brown rice after husking is easily damaged by the rice weevil.

Lesser grain borer

Angoumois grain moth

Rice weevil