Locust attack is not new and happens frequently. Just last year around 3.75 lakh hectares of crops were devoured by locust attacks in India with a loss of over Rs 100 crore, Ministry of Agriculture estimates suggest. However, this year the attack is one of the most severe in the last 27 years and has already damaged 2 lakh hectares of crop in May with the threat of potentially damaging another 6 lakh hectares. At present agricultural damage has been limited since we are in between two farming cycles. However, if the locusts stay on till the Kharif season starts, it can lead to crippling of the already weak agricultural economy of India and can endanger the food security of the country.
Locust Migration: When and where did it start?
Locust swarms have been devastating human livelihood for centuries and is described as the 8th Plague in the Bible. The outbreak that we are seeing now started in the Arabian Peninsula (deserts of Oman) back in 2018. The unusually high rainfall provided the locusts with ideal breeding conditions. However, due to the lack of vegetation in deserts, they formed swarms and migrated towards Africa, Iran and eastern Pakistan in search of food. By 2019, locust attacks had already created havoc in the Horn of Africa and authorities struggled to combat the crisis even with widespread spraying of pesticides. Earlier this month, huge locust swarms were spotted in Rajasthan coming from Pakistan. They are now moving towards Orissa and West Bengal drawn by the local cyclonic conditions. Finally, with the advent of monsoon it is expected that the locust swarms will move westward back towards Rajasthan following the wind direction. However, we must make sure that they don’t lay eggs in the agricultural lands of eastern India before proceeding westwards.
Locust Biology: How isolated grasshoppers become gregarious locusts
In simple words, locusts are large groups of grasshoppers. Grasshoppers are solitary insects. When a small number of hoppers come in close proximity and their hind legs rub against one another, they release a “happy hormone” called Serotonin that initiates their transformation to the “gregarious” phenotype. Serotonin is a molecule which is also found in our brain and controls our mood and sleep patterns. Once transformed into the “gregarious” phenotype, they change their body color to yellow/black and start migrating in search of food.
Climate change and Locust migration
Locusts are generally found in arid desert conditions where they eventually die out of natural mortality. However, their migration patterns are heavily influenced by climatic conditions. The exact mechanism how climate change affects locust swarms is yet to be determined. Some reports indicate that locust attacks are more prevalent in warmer and moist conditions. Climate change has led to global warming and more specifically warmer oceans. Warmer oceans give rise to cyclonic conditions which leads to unusually high precipitation. Experts believe this is the reason why Africa has been one of the worst affected areas from locust attacks. It also makes sense in terms of the eastward migration of locust swarms we are seeing today fueled by cyclonic conditions in eastern India and above average precipitation. A separate study from China suggests the contrary – that warmer climate leads to fewer locusts. While climate experts are still figuring out the exact relation between climate change and locust migration, it is also being speculated that wind patterns and precipitation might have a more influential role to play in predicting locust attacks than temperature alone.
Short-term solutions can be dangerous
For decades, locust attacks have been controlled by spraying chemical pesticides into agricultural lands. Although these are highly effective and act very fast, chemical pesticides are mainly organophosphates which are some of the most toxic compounds that exist today. Many of the compounds are neurotoxic and have carcinogenic effects. When sprayed into agricultural lands these pesticides contaminate our food and water resources and can have devastating effects on our health. Additionally, pesticides have been shown to degrade faster under warmer conditions. Hence, as the planet gets warmer due to global warming, we will end up needing much more amount of these toxic chemicals to achieve the same effects.
In addition to spraying pesticides, another way that has been adopted to control locust population in some parts of the world is by consuming locusts as food or using these as chicken feeds. This is an equally dangerous practice since many of the locusts may be already contaminated with harmful pesticides.
Biopesticides provide a sustainable alternative
Across the world, mass spraying of fields with chemical pesticides is the primary weapon against locusts. In times of such crisis, the governments must refrain from taking such ad-hoc measures that will have severe long term health consequences. Pesticides derived from biological origin, or Biopesticides provide a more eco-friendly, safer, and sustainable alternative to chemical pesticides. Biopesticides can contain naturally occurring chemicals like pheromones (Biochemical pesticides), microbial organisms like bacterium, fungus (microbial pesticides) or genetically engineered plants to express insecticidal proteins (Plant-Incorporated-Protectants).
Farmers in Africa have started using a fungus called Metarhizium acridum as a biopesticide to control the recent locust attacks. However, excessive spraying of fungal pesticides can also lead to prophylactic immunity and resistance in Locusts, especially when they are present in high population density. (Reference) India has centuries of experience with locust attacks and its Locust Warning Organization (LWO) was established during the colonial era specifically to tackle this problem. One of the most preferred biopesticide against locusts in India is based on oil extracted from the Neem plant (Azadirachta indica). Indian authorities have advised using 5% Neem seed kernel oil to spray in agricultural lands even before locusts arrive since Neem oil is an insect repellant as well as a potent pesticide.
Biopesticides market in India: Needs lot of support.
India till very recently remained one of the largest producers of chemical pesticides in the world. However, in May 2020, the Indian government banned production of 27 pesticides drawing flak from the strong organophosphate lobby. This was a bold step amidst an impending locust attack and is highly commendable. However, there is lot more to do to bolster the Biopesticide market. India with her tremendous natural resources, strong foundation in biopesticide research and being a large agricultural economy, has unparalleled potential as well as market for developing Biopesticides. It is surprising to note that India has only 14 registered Biopesticides whereas a country like US has around 366 registered active ingredients of Biopesticides as of 2018.
Senior journalist TV Padma wrote a detailed article in 2019 laying out the various challenges faced by the Biopesticide sector in India which I will attempt to summarize here (Click here for full article) –
Registering a new Biopesticide in India is expensive and a long drawn-out process.
Biopesticide companies are required to verify each microorganism for biosafety. Universities conducting research in Biopesticides do not have the resources to conduct large scale safety and allergy tests.
Biopesticide production is a high-risk venture requiring a high initial capital investment.
Single biggest constraint to Biopesticide development and growth is the rampant sale of sub-standard or spurious biopesticides, and biopesticides contaminated with chemical pesticides.
India till date has only 14 registered Biopesticides and this number hasn’t changed for many years. There is an urgent need to fast track the registration process as well as incentivize companies to perform large scale safety tests. For example, the registration of microorganisms can be expedited using DNA barcoding technology. Further, biopesticides that do not contain microbes or genetically engineered molecules should be made to pass through a more relaxed regulatory and safety requirements.
Finally, as per Chetan Keswani, a faculty at Benaras Hindu University, “India needs an integrated federal action plan, realistic funding and smooth administrative mechanisms for the registration and marketing of biopesticides. For harvesting maximum benefits, farmers should also be trained properly on how to use biopesticides,”