Generally, I am not the kind of person to write about social issues. However, whenever I scroll through Bangladeshi newspapers, I become worried about several issues that we are responsible for, which, without us acting on them, keep getting worse.
This year, hundreds of people died of dengue. I know policy-makers and the common people are more concerned about the treatments and the chemicals to eliminate the pest. However, we are missing one important aspect: Scientific expedition.
From 2019 to 2021, I worked with insecticide resistance that evolved in a notorious rice pest, Rice Brown Planthopper (BPH), which is commonly known as gunguni poka, or karent poka in Bangladesh. My research was focused on monitoring the status of insecticide resistance, the mechanisms contributed for the resistance development, and any cross-resistance.
Before going further, it is better to know what insecticide resistance is, which is a common question. In general, resistance is developed when a pest or a pathogen or any living being becomes tolerant to any stress; that stress might be chemical, environmental, or any other kind.
For insecticide resistance, when we continuously use similar kinds of chemicals to control a specific insect pest or a pathogen for several years, their mortality rate is reduced. In other words, they became tolerant to those chemicals, which we term as "evolution of insecticide resistance."
Let's go back to my research experiences. Before the Covid-19 pandemic, I used pest collected from different locations in China, and during the pandemic I collected this rice pest from three districts in Bangladesh. Then, I used a common method to find the level of resistance of this pest against commonly used insecticides in both countries; although, for Bangladesh, it was not possible to conduct a molecular study to understand its mechanism.
I found that this rice pest had already developed resistance to several insecticides, and although some of the insecticides were rarely used in China, most of the insecticides are in use in Bangladesh. In 2021, my findings were published in a crop protection journal.
In China, as rice is one of their main food crops, they emphasize on rice research and spend a huge amount of money for funding this research, mainly for basic research rather than releasing new varieties every year. Their ministry of agriculture also monitors the resistance development status regularly, collaborates with universities and research institutes, and acts based on the data.
I found that I am the only person who conducted such a research in Bangladesh for the first time. This is not a complicated research, but it's the basis for further investigation to know the actual situation.
There was a pest outbreak in China in 2005, and nearby rice producing countries, and the evolution of insecticide resistance was the key factor for that outbreak.
This phenomenon is not just about the mortality of the pest, but it also increased the number of offsprings of the pest known as "fecundity." So, when the pest developed certain levels of resistance, their population also increased exponentially, which is alarming.
As the term is resistance in pests, I had to read several articles on different types of insect species. During that time, I found a Nature article titled "Insecticide resistance in mosquito vectors" published in 2003, that mentioned mosquito vectors for malaria developed resistance since 1980s in Africa, America, and Europe.
In Bangladesh, dengue fever and its vector mosquito was common only in major, polluted cities, but currently it has spread to almost all districts. I do not know if policy-makers are planning to conduct any investigation before it becomes a pandemic, or just importing chemicals without knowing their efficacy in controlling these vectors.
However, there are many research organizations and universities in Bangladesh who may play a vital role in investigating the problem and suggesting policy-makers according to their findings.
It is not just mosquitoes or rice pest; the problem may present in many other crop pests that we need to evaluate. We need to come forward together for basic research, without bias, for our own benefit.
Juel Datta is former researcher, China National Rice Research Institute & Bangladesh Rice Research Institute. E-mail: [email protected]
